WO2015062261A1

WO2015062261A1 - Circuit for adjusting pull-up voltage of bus according to pull-up voltage of slave device, and method therefor

Info

Publication number: WO2015062261A1
Application number: PCT/CN2014/078370
Authority: WO
Inventors: 程龙飞; 朱少佞; 丁福波; 翟小兵; 徐波; 方斌华
Original assignee: 华为技术有限公司
Priority date: 2013-10-30
Filing date: 2014-05-26
Publication date: 2015-05-07
Also published as: CN103546114A; CN103546114B

Abstract

Provided are a circuit for adjusting a pull-up voltage of a bus according to a pull-up voltage of a slave device, and a method therefor.The circuit comprises a bus, a voltage dividing unit, a comparator, a latch and an impedance unit, wherein the voltage dividing unit conducts voltage dividing on a voltage output by a first power source so as to acquire a divided voltage;a first input end of the comparator receives the divided voltage, a second input end of the comparator receives a pull-up voltage of a slave device through a bus, and an output end of the comparator outputs a comparison result;and a first input end of the latch receives the comparison result, a second input end of the latch receives a trigger signal, an output end of the latch outputs a control signal to control a resistance value of a pull-up resistor of the impedance unit accessing the bus, so that the pull-up voltage formed by the pull-up resistor of the bus is equal to that of the slave device, thereby realizing voltage matching.In the manner, the pull-up voltage on the bus can be automatically increased according to the operating voltage of the slave device, thereby realizing voltage matching.

Description

根据从设备的上拉电压调整总线上拉电压的电路及其方法本申请要求于 2013年 10月 30日提交中国专利局、申请号为 Circuit and method for adjusting bus pull-up voltage according to pull-up voltage of device: The application is filed on October 30, 2013 and submitted to the Chinese Patent Office, and the application number is

201310530312.9, 发明名称为' 根据从设备的上拉电压调整总线上拉电压的电路及其方法" 的中国专利申请的优先权，其全部内容通过引用结合在本申请中。 201310530312.9, the title of the present invention is the priority of the Chinese Patent Application, which is incorporated herein by reference.

技术领域 Technical field

本发明涉及电源技术领域，特别是涉及一种根据从设备的上拉电压调整总线上拉电压的电路及其方法。背景技术 The present invention relates to the field of power supply technologies, and more particularly to a circuit and method for adjusting a bus pull-up voltage in accordance with a pull-up voltage of a slave device. Background technique

目前机架服务器用的 AC-DC (交流转直流， alternating current-Direct Current )电源模块有 750W、 800W和 1200W等多种功率类型且有不同的供应商。其中 750W和 1200W是一个厂家的， 800W是另外一个厂家的。 750W和 1200W的电源模块的通信接 DIIC (集成电路总线， Inter-Integrated Circuit ) 的上拉电源是 5V ,上拉电阻为 20K ,上拉电源集成在电源模块内部。 800W 电源模块的通信接口 IIC的上拉电源是 3.3V ,上拉电阻为 20K ,上拉电源集成在电源模块内部。电源模块的器件资料明确要求，电源模块外部的 PCB 走线上需要加上拉电阻，且该上拉电阻形成的上拉电压和电源模块内部的上拉电压相同。 At present, AC-DC (AC-DC) power modules for rack servers have various power types of 750W, 800W and 1200W and have different suppliers. Among them, 750W and 1200W are one manufacturer, and 800W is another manufacturer. The communication between the 750W and 1200W power modules is connected to the DIIC (Inter-Integrated Circuit) with a pull-up power supply of 5V and a pull-up resistor of 20K. The pull-up power supply is integrated inside the power module. The communication interface of the 800W power module IIC has a pull-up power supply of 3.3V and a pull-up resistor of 20K. The pull-up power supply is integrated inside the power module. The device data of the power module clearly requires that a pull-up resistor be added to the PCB trace outside the power module, and the pull-up voltage formed by the pull-up resistor is the same as the pull-up voltage inside the power module.

由于上述的两种电源模块要求的上拉电源不一样：一个是 3.3V ,—个是 5V ,彼此产生冲突。 IIC的上拉是硬件上直接实现的，无法智能的根据电源模块的类型实现两种电源的电压之间的切换。如果一款服务器需要兼容两个厂家的电源模块，硬件设计上无法兼容。个别的服务器产品就是因为无法实现二者的兼容，在规格中强制去掉了一个电源模块，例如 800W的电源模块的兼容，这将降低服务器电源模块的适用性。发明内容 Since the above two power modules require different pull-up power supplies: one is 3.3V, and the other is 5V, which conflicts with each other. The pull-up of the IIC is directly implemented on the hardware, and it is impossible to intelligently switch between the voltages of the two power sources according to the type of the power module. If a server needs to be compatible with two manufacturers' power modules, the hardware design is not compatible. Individual server products are unable to achieve compatibility between the two, and a power module is forcibly removed from the specification, such as the compatibility of 800W power modules, which will reduce the applicability of the server power module. Summary of the invention

本发明主要解决的技术问题是提供一种根据从设备的上拉电压调整总线上拉电压的电路及其方法，能够根据从设备的工作电压，自动增加总线的上拉电压，从而实现电压匹配。 The technical problem mainly solved by the present invention is to provide a total adjustment according to the pull-up voltage of the slave device. The circuit for pulling voltage on the line and the method thereof can automatically increase the pull-up voltage of the bus according to the operating voltage of the slave device, thereby achieving voltage matching.

第一方面提供一种根据从设备的上拉电压调整总线上拉电压的电路，该电路包括总线、分压单元、比较器、锁存器以及阻抗单元，总线与从设备电连接，其中：分压单元对第一电源输出的电压进行分压，以获取分压电压，第一电源是同一类型的连接方式对应的多种从设备中上拉电压值最大的电源；比较器的第一输入端接收分压电压，比较器的第二输入端通过总线接收从设备的上拉电压，比较器的输出端输出比较结果；锁存器的第一输入端接收比较结果，锁存器的第二输入端接收一触发信号，锁存器的输出端输出控制信号控制阻抗单元接入总线的上拉电阻的阻值，使得总线的上拉电阻形成的上拉电压与从设备的上拉电压相等，实现电压匹配。 The first aspect provides a circuit for adjusting a bus pull-up voltage according to a pull-up voltage of a device, the circuit comprising a bus, a voltage dividing unit, a comparator, a latch, and an impedance unit, wherein the bus is electrically connected to the slave device, wherein: The voltage unit divides the voltage of the first power output to obtain a voltage dividing voltage, and the first power source is a power source with the largest pull-up voltage value of the plurality of slave devices corresponding to the same type of connection mode; the first input end of the comparator Receiving a divided voltage, the second input of the comparator receives the pull-up voltage of the slave device through the bus, and the output of the comparator outputs a comparison result; the first input of the latch receives the comparison result, and the second input of the latch The terminal receives a trigger signal, and the output of the latch outputs a control signal to control the resistance of the pull-up resistor of the impedance unit to the bus, so that the pull-up voltage formed by the pull-up resistor of the bus is equal to the pull-up voltage of the slave device, Voltage matching.

在第一方面的第一种可能的实施方式中，，分压电路包括第一电阻和第二电阻，第一电阻的一端连接第一电源，第一电阻的另一端连接第二电阻的一端和比较器的第一输入端，第二电阻的第二端接地。 In a first possible implementation manner of the first aspect, the voltage dividing circuit includes a first resistor and a second resistor, one end of the first resistor is connected to the first power source, and the other end of the first resistor is connected to one end of the second resistor and A first input of the comparator, the second end of the second resistor is grounded.

结合第一方面的第一种可能的实施方式，在第二种可能的实施方式中，比较器的第一输入端为负向输入端，比较器的第二输入端为正向输入端，锁存器的输出端为同相输出端。 In conjunction with the first possible implementation of the first aspect, in a second possible implementation, the first input of the comparator is a negative input, and the second input of the comparator is a positive input, the lock The output of the register is the non-inverting output.

结合第一方面的第一种可能的实施方式，在第三种可能的实施方式中，比较器的第一输入端为正向输入端，比较器的第二输入端为负向输入端，锁存器的输出端为反相输出端。 In conjunction with the first possible implementation of the first aspect, in a third possible implementation, the first input of the comparator is a positive input, and the second input of the comparator is a negative input, the lock The output of the register is the inverting output.

结合第一方面的第二种或第三种可能的实施方式，在第四种可能的实施方式中，总线包括数据总线和时钟总线，阻抗单元包括第一开关管、第二开关管、第三开关管、第三电阻、第四电阻、第五电阻、第六电阻、第七电阻以及第八电阻，其中，锁存器的输出端连接第一开关管的棚极和第二开关管的棚极，第二开关管的源极接地，第二开关管的漏极连接第三电阻的一端，第三电阻的另一端连接一第二电源，第一开关管的源极接地，第一开关管的漏极连接第四电阻的一端以及第三开关管的棚极，第四电阻的另一端连接第五电阻的一端以及第一电源，第五电阻的另一端连接第三开关管的漏极、第六电阻和第七电阻的一端，第三开关管的源极接地，第六电阻的另一端连接时钟总线，第七电阻的另一端连接第八电阻的一端以及第二开关管的漏极，第八电阻的另一端连接数据总线，其中，第二电源对应的从设备和第一电源对应的从设备是同一类型的连接方式中的两种从设备，并且第二电源的上拉电压小于第一电源的上拉电压。 With reference to the second or third possible implementation manner of the first aspect, in a fourth possible implementation, the bus includes a data bus and a clock bus, and the impedance unit includes a first switch tube, a second switch tube, and a third a switch tube, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, and an eighth resistor, wherein the output end of the latch is connected to the shed of the first switch tube and the shed of the second switch tube a pole, a source of the second switch is grounded, a drain of the second switch is connected to one end of the third resistor, and the other end of the third resistor is connected to a second power source, the source of the first switch is grounded, the first switch The drain is connected to one end of the fourth resistor and the gate of the third switch tube, the other end of the fourth resistor is connected to one end of the fifth resistor and the first power source, and the other end of the fifth resistor is connected to the drain of the third switch tube, One end of the sixth resistor and the seventh resistor, the source of the third switch tube is grounded, the other end of the sixth resistor is connected to the clock bus, and the other end of the seventh resistor is connected to one end of the eighth resistor And a drain of the second switch, the other end of the eighth resistor is connected to the data bus, wherein the slave device corresponding to the second power source and the slave device corresponding to the first power source are two slave devices in the same type of connection manner, and The pull-up voltage of the second power source is less than the pull-up voltage of the first power source.

结合第一方面的第四种可能的实施方式，在第五种可能的实施方式中，从设备通过总线与主设备电连接，电路还包括第三电源、第四开关管和第五开关管，第四开关管设置在数据总线上，第五开关管设置在时钟总线上，第四开关管和第五开关管的棚极接收第三电源输出的电压，第四开关管和第五开关管的源极电连接主设备，第四开关管和第五开关管的漏极电连接从" L殳备。 In conjunction with the fourth possible implementation of the first aspect, in a fifth possible implementation, the slave device is electrically connected to the master device by using a bus, and the circuit further includes a third power source, a fourth switch tube, and a fifth switch tube. The fourth switch tube is disposed on the data bus, the fifth switch tube is disposed on the clock bus, the gates of the fourth switch tube and the fifth switch tube receive the voltage outputted by the third power source, and the fourth switch tube and the fifth switch tube The source is electrically connected to the main device, and the drains of the fourth switch and the fifth switch are electrically connected from the "L".

结合第一方面的第五种可能的实施方式，在第六种可能的实施方式中，电路还包括第四电源、第九电阻和第十电阻，第九电阻和第十电阻的一端接收第四电源输出的电压，第九电阻和第十电阻的另一端分别电连接数据总线和时钟总线。 In conjunction with the fifth possible implementation of the first aspect, in a sixth possible implementation, the circuit further includes a fourth power source, a ninth resistor, and a tenth resistor, and one end of the ninth resistor and the tenth resistor receives the fourth The voltage of the power output, the other ends of the ninth resistor and the tenth resistor are electrically connected to the data bus and the clock bus, respectively.

结合第一方面的第六种可能的实施方式，在第七种可能的实施方式中，比较器还包括电源端和接地端，电源端接收第一电源电压，接地端接地。 In conjunction with the sixth possible implementation of the first aspect, in a seventh possible implementation, the comparator further includes a power terminal and a ground terminal, the power terminal receives the first power voltage, and the ground terminal is grounded.

结合第一方面的第四种可能的实施方式，在第八种可能的实施方式中，分压电压大于第二电源的上拉电压，并小于第一电源的上拉电压。 In conjunction with the fourth possible implementation of the first aspect, in an eighth possible implementation, the voltage divider voltage is greater than a pull-up voltage of the second power source and less than a pull-up voltage of the first power source.

第二方面提供一种根据从设备的上拉电压调整总线上拉电压的方法，该方法包括以下步骤： The second aspect provides a method for adjusting a bus pull-up voltage according to a pull-up voltage of a slave device, the method comprising the steps of:

对第一电源输出的电压进行分压，以获取分压电压，其中，第一电源是同一类型的连接方式对应的多种从设备中上拉电压值最大的电源； And dividing a voltage of the output of the first power source to obtain a voltage dividing voltage, wherein the first power source is a power source having the largest pull-up voltage value among the plurality of slave devices corresponding to the same type of connection mode;

比较分压电压和从设备的上拉电压的大小，并输出比较结果；根据比较结果输出控制信号控制接入总线的上拉电阻的阻值，使得总线的上拉电阻形成的上拉电压与从设备内的上拉电压相等，实现电压匹配，其中，总线与从设备电连接。 Comparing the voltage of the divided voltage and the pull-up voltage of the slave device, and outputting the comparison result; according to the comparison result, the output control signal controls the resistance of the pull-up resistor of the access bus, so that the pull-up voltage formed by the pull-up resistor of the bus and the slave The pull-up voltages in the device are equal to achieve voltage matching, wherein the bus is electrically connected to the slave device.

在第二方面的第一种可能的实施方式中，对第一电源输出的电压进行分压，以获取分压电压的步骤进一步包括：对第一电源输出的电压进行分压后获取的分压电压大于第二电源的上拉电压，并小于第一电源的上拉电压；其中，第二电源对应的从设备和第一电源对应的从设备是同一类型的连接方式中的两种从设备，并且第二电源的上拉电压小于第一电源的上拉电压。 In a first possible implementation manner of the second aspect, the step of dividing the voltage of the first power output to obtain the divided voltage further includes: dividing the voltage obtained by dividing the voltage output by the first power source The voltage is greater than the pull-up voltage of the second power source, and is smaller than the pull-up voltage of the first power source; wherein the slave device corresponding to the second power source and the slave device corresponding to the first power source are two slave devices in the same type of connection manner, And the pull-up voltage of the second power source is less than the pull-up of the first power source Voltage.

结合第二方面的第一种可能的实施方式，在第二种可能的实施方式中，比较分压电压和从设备的上拉电压的大小，并输出比较结果的步骤进一步包括：当分压电压大于从设备的上拉电压时，比较结果为 0；当分压电压小于从设备的上拉电压时，比较结果为 1。 In conjunction with the first possible implementation of the second aspect, in a second possible implementation, the step of comparing the voltage of the divided voltage and the pull-up voltage of the slave device and outputting the comparison result further includes: when the voltage divider voltage is greater than When the voltage is pulled up from the device, the comparison result is 0; when the divided voltage is less than the pull-up voltage of the slave device, the comparison result is 1.

结合第二方面的第二种可能的实施方式，在第三种可能的实施方式中，根据比较结果输出控制信号的步骤进一步包括：当比较结果为 1 时，输出控制信号 1；当比较结果为 0时，输出控制信号 0。 With reference to the second possible implementation manner of the second aspect, in a third possible implementation, the step of outputting the control signal according to the comparison result further includes: when the comparison result is 1, outputting the control signal 1; when the comparison result is When 0, the control signal 0 is output.

结合第二方面的第一种可能的实施方式，在第四种可能的实施方式中，比较分压电压和从设备的上拉电压的大小，并输出比较结果的步骤进一步包括：当分压电压大于从设备的上拉电压时，比较结果为 1；当分压电压小于从设备的上拉电压时，比较结果为 0。 In conjunction with the first possible implementation of the second aspect, in a fourth possible implementation, the step of comparing the voltage of the divided voltage and the pull-up voltage of the slave device and outputting the comparison result further includes: when the voltage divider voltage is greater than When the voltage is pulled up from the device, the comparison result is 1; when the divided voltage is less than the pull-up voltage of the slave device, the comparison result is 0.

结合第二方面的第四种可能的实施方式，在第五种可能的实施方式中，根据比较结果输出控制信号的步骤进一步包括：当比较结果为 1 时，输出控制信号 0；当比较结果为 0时，输出控制信号 1。 With reference to the fourth possible implementation manner of the second aspect, in a fifth possible implementation, the step of outputting the control signal according to the comparison result further includes: when the comparison result is 1, outputting the control signal 0; when the comparison result is When 0, the control signal 1 is output.

本发明的有益效果是：区别于现有技术的情况，本发明通过分压单元对第一电源输出的电压进行分压，以获取分压电压，比较器比较分压电压以及从设备的上拉电压，并输出比较结果，锁存器接收比较结果，并在一触发信号的作用下输出控制信号控制阻抗单元接入总线的上拉电阻的阻值，使得总线的上拉电阻形成的上拉电压与从设备的上拉电压相等，实现电压匹配。通过上述方式，本发明根据从设备的上拉电压调整总线上拉电压的电路能自动识别从设备的上拉电压（即工作电压），并根据该上拉电压来判断设备的类型，从而自动调整总线的上拉电压，使得总线的上拉电压与从设备的上拉电压相等，从而实现电压匹配。 The beneficial effects of the present invention are: different from the prior art, the present invention divides the voltage of the first power output by the voltage dividing unit to obtain the divided voltage, and the comparator compares the divided voltage and the pull-up of the slave device. Voltage, and output comparison result, the latch receives the comparison result, and outputs a control signal under the action of a trigger signal to control the resistance of the pull-up resistor of the impedance unit to the bus, so that the pull-up voltage formed by the pull-up resistor of the bus Voltage matching is achieved by equalizing the pull-up voltage of the slave device. In the above manner, the present invention can automatically recognize the pull-up voltage (ie, the operating voltage) of the slave device according to the pull-up voltage of the slave device by adjusting the pull-up voltage of the slave device, and determine the type of the device according to the pull-up voltage, thereby automatically adjusting The pull-up voltage of the bus is such that the pull-up voltage of the bus is equal to the pull-up voltage of the slave device, thereby achieving voltage matching.

附图说明 DRAWINGS

图 1 是本发明实施例提供的一种根据从设备的上拉电压调整总线上拉电压的电路的结构框图；图 2是本发明实施例提供的一种根据从设备的上拉电压调整总线上拉电压的电路的结构示意图； 1 is a structural block diagram of a circuit for adjusting a bus pull-up voltage according to a pull-up voltage of a slave device according to an embodiment of the present invention; 2 is a schematic structural diagram of a circuit for adjusting a bus pull-up voltage according to a pull-up voltage of a slave device according to an embodiment of the present invention;

图 3是本发明实施例提供的一种根据从设备的上拉电压调整总线上拉电压的方法的流程图。具体实施方式 FIG. 3 is a flowchart of a method for adjusting a bus pull-up voltage according to a pull-up voltage of a slave device according to an embodiment of the present invention. detailed description

请参阅图 1 ,图 1是本发明实施例提供的一种根据从设备的上拉电压调整总线上拉电压的电路的结构框图。如图 1 所示，本发明的根据从设备的上拉电压调整总线上拉电压的电路 10包括总线 11、分压单元 12、比较器 13、锁存器 14、阻抗单元 15以及从设备 100。 Referring to FIG. 1, FIG. 1 is a structural block diagram of a circuit for adjusting a bus pull-up voltage according to a pull-up voltage of a slave device according to an embodiment of the present invention. As shown in Fig. 1, the circuit 10 for adjusting the bus pull-up voltage according to the pull-up voltage of the slave device of the present invention comprises a bus 11, a voltage dividing unit 12, a comparator 13, a latch 14, an impedance unit 15, and a slave device 100.

其中，从设备 100通过总线 11电连接主设备 111。 Among them, the slave device 100 is electrically connected to the master device 111 via the bus 11.

分压单元 12对第一电源 VSTB 1输出的电压进行分压，以获取分压电压，其中，第—电源 _{VSTB 1}是同一类型的连接方式对应的多种从设备 100 中上拉电压值最大的电源。 The voltage dividing unit 12 divides the voltage outputted by the first power source VSTB 1 to obtain a voltage dividing voltage, wherein the first power source _{VSTB 1} is the largest pull-up voltage value of the plurality of slave devices 100 corresponding to the same type of connection mode. power supply.

比较器 13的第一输入端 131接收分压电压，比较器 13的第二输入端 The first input 131 of the comparator 13 receives the divided voltage, and the second input of the comparator 13

132通过总线 11接收从设备 100的上拉电压，比较器 13的输出端 133输出比较结果。 The pull-up voltage of the slave device 100 is received by the bus 11, and the output 133 of the comparator 13 outputs the comparison result.

锁存器 14的第一输入端 S接收比较结果，锁存器 14的第二输入端 C 接收一触发信号 M ,锁存器 14的输出端 Q输出控制信号控制阻抗单元 15 接入总线 11的上拉电阻的阻值，使得总线 11的上拉电阻形成的上拉电压与从设备 100的上拉电压相等，实现电压匹配。 The first input terminal S of the latch 14 receives the comparison result, the second input terminal C of the latch 14 receives a trigger signal M, and the output terminal Q of the latch 14 outputs a control signal to control the impedance unit 15 to access the bus 11. The resistance of the pull-up resistor is such that the pull-up voltage formed by the pull-up resistor of the bus 11 is equal to the pull-up voltage of the slave device 100, achieving voltage matching.

本实施例中，通过分压单元 12对第一电源 VSTB 1输出的电压进行分压，以获取分压电压，比较器 13比较分压电压以及从设备 100的上拉电压，并输出比较结果，锁存器 14根据该比较结果控制阻抗单元 15接入总线 11 的上拉电阻的阻值，使得根据从设备的上拉电压调整总线上拉电压的电路 In this embodiment, the voltage output from the first power source VSTB 1 is divided by the voltage dividing unit 12 to obtain a divided voltage, and the comparator 13 compares the divided voltage and the pull-up voltage of the slave device 100, and outputs a comparison result. The latch 14 controls the resistance of the impedance unit 15 to the pull-up resistor of the bus 11 according to the comparison result, so that the bus pull-up voltage is adjusted according to the pull-up voltage of the slave device.

10能自动识别从设备 100的上拉电压（即工作电压），并根据该上拉电压来判断从设备 100的类型，从而自动调整总线 11 的上拉电阻，使得总线 11 的上拉电阻形成的上拉电压与从设备 100的上拉电压相等，从而实现电压匹配。 10 can automatically recognize the pull-up voltage (ie, the operating voltage) of the slave device 100, and determine the type of the slave device 100 according to the pull-up voltage, thereby automatically adjusting the pull-up resistor of the bus 11, so that the pull-up resistor of the bus 11 is formed. The pull-up voltage is equal to the pull-up voltage of the slave device 100 to achieve voltage matching.

本发明实施例还提供了另一种根据从设备的上拉电压调整总线上拉电压的电路，其是在上述实施例的基础上进行详细描述。其中，本实施例的根据从设备的上拉电压调整总线上拉电压的电路 10以调整总线 11的两个不同的上拉电压值、识别不同上拉电压的两种从设备为例进行说明，应理解，本发明并不限于此具体实施例。 The embodiment of the present invention further provides another method for adjusting the power of the bus according to the pull-up voltage of the slave device. The circuit of the voltage is described in detail on the basis of the above embodiment. In the embodiment, the circuit 10 for adjusting the bus pull-up voltage according to the pull-up voltage of the slave device is described by taking two kinds of slave devices that adjust two different pull-up voltage values of the bus 11 and identify different pull-up voltages as an example. It should be understood that the invention is not limited to this particular embodiment.

具体请参阅图 2 ,分压电路 12包括第一电阻 R1和第二电阻 R2 ,总线 11优选为 IIC总线，其包括数据总线 DATA和时钟总线 CLK。第一电阻 R1 的一端连接第一电源 VSTB1 ,第一电阻 R1的另一端连接第二电阻 R2的一端和比较器 13的第一输入端 131 ,第二电阻 R2的第二端接地。比较器 13 的第二输入端 132电连接数据总线 DATA。比较器 13的输出端 133电连接锁存器 14的第一输入端 S。比较器 13还包括电源端和接地端，其中，电源端连接第一电源 VSTB1 ,接地端接地。 Referring to FIG. 2, the voltage dividing circuit 12 includes a first resistor R1 and a second resistor R2. The bus 11 is preferably an IIC bus, which includes a data bus DATA and a clock bus CLK. One end of the first resistor R1 is connected to the first power source VSTB1, and the other end of the first resistor R1 is connected to one end of the second resistor R2 and the first input terminal 131 of the comparator 13, and the second end of the second resistor R2 is grounded. The second input 132 of the comparator 13 is electrically coupled to the data bus DATA. The output 133 of the comparator 13 is electrically coupled to the first input S of the latch 14. The comparator 13 further includes a power terminal and a ground terminal, wherein the power terminal is connected to the first power source VSTB1 and the ground terminal is grounded.

进一步地，阻抗单元 15包括第一开关管 Ql、第二开关管 Q2、第三开关管 Q3、第三电阻 R3、第四电阻 R4、第五电阻 R5、第六电阻 R6、第七电阻 R7和第八电阻 R8。其中，锁存器 14的输出端 Q连接第一开关管 Q1 的棚极和第二开关管 Q2的棚极，第二开关管 Q2的源极接地，第二开关管 Q2的漏极连接第三电阻 R3的一端，第三电阻 R3的另一端连接第二电源 VSTB2 ,第一开关管 Q1的源极接地，第一开关管 Q1的漏极连接第四电阻 R4的一端以及第三开关管 Q3的棚极，第四电阻 R4的另一端连接第五电阻 R5的一端以及第一电源 VSTB1 ,第五电阻 R5的另一端连接第三开关管 Q3 的漏极、第六电阻 R6和第七电阻 R7的一端，第三开关管 Q3的源极接地，第六电阻 R6的另一端连接时钟总线 CLK ,第七电阻 R7的另一端连接第八电阻 R8的一端以及第二开关管 Q2的漏极，第八电阻 R8的另一端连接数据总线 DATA。 Further, the impedance unit 15 includes a first switching transistor Q1, a second switching transistor Q2, a third switching transistor Q3, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and The eighth resistor R8. The output terminal Q of the latch 14 is connected to the gate of the first switching transistor Q1 and the gate of the second switching transistor Q2, the source of the second switching transistor Q2 is grounded, and the drain of the second switching transistor Q2 is connected to the third. One end of the resistor R3, the other end of the third resistor R3 is connected to the second power source VSTB2, the source of the first switching transistor Q1 is grounded, the drain of the first switching transistor Q1 is connected to one end of the fourth resistor R4 and the third switching transistor Q3 The other end of the fourth resistor R4 is connected to one end of the fifth resistor R5 and the first power source VSTB1, and the other end of the fifth resistor R5 is connected to the drain of the third switch transistor Q3, the sixth resistor R6 and the seventh resistor R7. One end, the source of the third switch Q3 is grounded, the other end of the sixth resistor R6 is connected to the clock bus CLK, and the other end of the seventh resistor R7 is connected to one end of the eighth resistor R8 and the drain of the second switch Q2, the eighth The other end of the resistor R8 is connected to the data bus DATA.

其中，第二电源 VSTB2对应的从设备 100和第一电源 VSTB1对应的从设备 100是同一类型的连接方式中的两种从设备。并且第二电源 VSTB2 的上拉电压小于第一电源 VSTB1的上拉电压。 The slave device 100 corresponding to the second power source VSTB2 and the slave device 100 corresponding to the first power source VSTB1 are two types of slave devices in the same type of connection mode. And the pull-up voltage of the second power source VSTB2 is smaller than the pull-up voltage of the first power source VSTB1.

值得注意的是，本实施例识别的两种从设备 100的上拉电压分别和第一电源 VSTB1的上拉电压和第二电源 VSTB2的上拉电压相等。 It should be noted that the pull-up voltages of the two slave devices 100 identified in this embodiment are equal to the pull-up voltage of the first power source VSTB1 and the pull-up voltage of the second power source VSTB2, respectively.

进一步地，本发明的根据从设备的上拉电压调整总线上拉电压的电路 10还包括第三电源 VSTB3、第四开关管 Q4和第五开关管 Q5 ,第四开关管 Q4设置在数据总线 DATA上，第五开关管 Q5设置在时钟总线 CLK上，第四开关管 Q4和第五开关管 Q5的棚极接收第三电源 VSTB3输出的电压，第四开关管 Q4和第五开关管 Q5的源极电连接主设备 101 ,第四开关管 Q4 和第五开关管 Q5的漏极电连接从设备 100。其中，第三电源 VSTB3的电压要大于第四开关管 Q4的导通电压以及第五开关管 Q5的导通电压，确保第四开关管 Q4和第五开关管 Q5能够工作。第三电源 VSTB3的电压还必须小于数据总线 DATA的上拉电压，实现主设备 101和从设备 100的电压隔离。因此，当数据总线 DATA的上拉电压等于第一电源 VSTB1的上拉电压时，第三电源 VSTB3也可以用第二电源 VSTB2替代。 Further, the circuit 10 for adjusting the bus pull-up voltage according to the pull-up voltage of the slave device of the present invention further includes a third power source VSTB3, a fourth switch transistor Q4, and a fifth switch transistor Q5, and a fourth switch transistor Q4 is set on the data bus DATA, the fifth switch tube Q5 is set on the clock bus CLK, the gates of the fourth switch tube Q4 and the fifth switch tube Q5 receive the voltage output by the third power source VSTB3, the fourth switch tube Q4 and the The source of the fifth switching transistor Q5 is electrically connected to the master device 101, and the drains of the fourth switching transistor Q4 and the fifth switching transistor Q5 are electrically connected to the slave device 100. The voltage of the third power source VSTB3 is greater than the turn-on voltage of the fourth switch tube Q4 and the turn-on voltage of the fifth switch tube Q5 to ensure that the fourth switch tube Q4 and the fifth switch tube Q5 can operate. The voltage of the third power source VSTB3 must also be less than the pull-up voltage of the data bus DATA to achieve voltage isolation between the master device 101 and the slave device 100. Therefore, when the pull-up voltage of the data bus DATA is equal to the pull-up voltage of the first power source VSTB1, the third power source VSTB3 can also be replaced with the second power source VSTB2.

进一步地，本发明的根据从设备的上拉电压调整总线上拉电压的电路 10还包括第四电源 VSTB4、第九电阻 R9和第十电阻 R10 ,第九电阻 R9 和第十电阻 R10的一端接收第四电源 VSTB4输出的电压，第九电阻 R9和第十电阻 R10的另一端分别电连接数据总线 DATA和时钟总线 CLK。其中，第九电阻 R9和第十电阻 R10作为主设备 101的上拉电阻第四电源 VSTB4 的电压可根据主设备 101 的要求设置，只要能向第九电阻 R9和第十电阻 R10提供足够的上拉电压即可。 Further, the circuit 10 for adjusting the bus pull-up voltage according to the pull-up voltage of the device of the present invention further includes a fourth power source VSTB4, a ninth resistor R9, and a tenth resistor R10, and one end of the ninth resistor R9 and the tenth resistor R10 are received. The voltage output from the fourth power source VSTB4, the other ends of the ninth resistor R9 and the tenth resistor R10 are electrically connected to the data bus DATA and the clock bus CLK, respectively. The voltages of the ninth resistor R9 and the tenth resistor R10 as the pull-up resistor fourth power source VSTB4 of the master device 101 can be set according to the requirements of the master device 101, as long as sufficient ninth resistor R9 and tenth resistor R10 can be provided. Pull the voltage.

以下将介绍根据从设备的上拉电压调整总线上拉电压的电路 10的工作原理： The following describes the operation of the circuit 10 for adjusting the bus pull-up voltage based on the pull-up voltage of the slave device:

在电路上电后且总线 11通信尚未开始前，通过比较器 13采样数据总线 DATA上的从设备 100的上拉电压，第一电源 VSTB1上电完成以后，分压单元 12对第一电源 VSTB1输出的电压进行分压，以获取分压电压。其中，第一电源 VSTB1经过分压后得到的分压电压小于第一电源 VSTB1的上拉电压并大于第二电源 VSTB2的上拉电压。比较器 13比较从设备 100 的上拉电压和分压电压的大小。锁存器 14的第一输入端 S接收比较器 13 的比较结果，锁存器 14的第二输入端 R接收一触发信号 M ,将比较器 13 输出的比较结果锁存，输出控制信号。阻抗单元 15根据锁存器 14输出的控制信号控制接入总线 11的上拉电阻的阻值，使得总线 11的上拉电阻形成的上拉电压与从设备 100的上拉电压相等，实现电压匹配。 After the circuit is powered up and the communication of the bus 11 has not yet started, the pull-up voltage of the slave device 100 on the data bus DATA is sampled by the comparator 13. After the power-on of the first power source VSTB1 is completed, the voltage dividing unit 12 outputs the first power source VSTB1. The voltage is divided to obtain a divided voltage. The divided voltage obtained by dividing the first power source VSTB1 is smaller than the pull-up voltage of the first power source VSTB1 and larger than the pull-up voltage of the second power source VSTB2. The comparator 13 compares the magnitude of the pull-up voltage and the divided voltage of the slave device 100. The first input terminal S of the latch 14 receives the comparison result of the comparator 13, and the second input terminal R of the latch 14 receives a trigger signal M, latches the comparison result output from the comparator 13, and outputs a control signal. The impedance unit 15 controls the resistance of the pull-up resistor of the access bus 11 according to the control signal output from the latch 14, so that the pull-up voltage formed by the pull-up resistor of the bus 11 is equal to the pull-up voltage of the slave device 100, and voltage matching is achieved. .

其中，触发信号 M可以为第一电源 VSTB1的 PG信号，也可以为其他的触发信号。锁存器 14锁存的动作只在第一次上电时进行，在总线 11正常工作时不动作。 The trigger signal M may be the PG signal of the first power source VSTB1, or may be other trigger signals. The latched action of latch 14 is only performed on the first power-on, on the bus 11 Does not work when working normally.

进一步的，比较器 13的比较结果和锁存器 14输出的控制信号会随着其各自的连接方式的改变而改变，有以下两种情况： Further, the comparison result of the comparator 13 and the control signal output from the latch 14 are changed as their respective connection modes are changed, and there are two cases:

第一种情况：比较器 13的第一输入端 131 为负向输入端，比较器 13 的第二输入端 132为正向输入端，锁存器 14的输出端 Q为同相输出端，连接方式如图 2所示； In the first case, the first input terminal 131 of the comparator 13 is a negative input terminal, the second input terminal 132 of the comparator 13 is a forward input terminal, and the output terminal Q of the latch 14 is a non-inverting output terminal. as shown in picture 2;

第二种情况：比较器 13的第一输入端 131 为正向输入端，比较器 13 的第二输入端 132为负向输入端，锁存器 14的输出端 Q为反相输出端，如图 2所示的 Q非端。 In the second case, the first input 131 of the comparator 13 is a forward input terminal, the second input terminal 132 of the comparator 13 is a negative input terminal, and the output terminal Q of the latch 14 is an inverted output terminal, such as The Q non-end shown in Figure 2.

当比较器 13和锁存器 14的连接方式属于第一种情况时，比较器 13和锁存器 14的具体工作过程如下： When the connection mode of the comparator 13 and the latch 14 belongs to the first case, the specific operation of the comparator 13 and the latch 14 is as follows:

如果比较器 13的第二输入端 132通过总线 11的数据总线 DATA接收从设备 100的上拉电压是和第一电源 VSTB1的上拉电压相等，则该上拉电压大于分压电压，比较器 131输出 1 ,如果比较器 13的第二输入端 132通过总线 11 的数据总线 DATA 接收从设备 100 的上拉电压是和第二电源 VSTB2的上拉电压相等时，则该上拉电压小于分压电压，比较器 13输出 0。 If the second input terminal 132 of the comparator 13 receives the pull-up voltage of the slave device 100 through the data bus DATA of the bus 11 to be equal to the pull-up voltage of the first power source VSTB1, the pull-up voltage is greater than the divided voltage, and the comparator 131 Output 1, if the second input 132 of the comparator 13 receives the pull-up voltage of the slave device 100 through the data bus DATA of the bus 11 is equal to the pull-up voltage of the second power source VSTB2, then the pull-up voltage is less than the divided voltage The comparator 13 outputs 0.

当比较器 13输出为 1时，锁存器 14在触发信号 M的作用下输出控制信号 1 ,控制第一开关管 Q1和第二开关管 Q2导通，第三开关管 Q3截止，使得第三电阻 R3被短路，此时，接入总线 11的上拉电阻为第五电阻 R5、第六电阻 R6、第七电阻 R7以及第八电阻 R8 ,因为此时第五电阻 R5、第六电阻 R6、第七电阻 R7以及第八电阻 R8的驱动电压为第一电源 VSTB1 的电压，因此接入总线 11的上拉电阻形成的上拉电压和从设备 10的上拉电压相等，实现电压的自动匹配。 When the output of the comparator 13 is 1, the latch 14 outputs a control signal 1 under the action of the trigger signal M, and controls the first switching transistor Q1 and the second switching transistor Q2 to be turned on, and the third switching transistor Q3 is turned off, so that the third The resistor R3 is short-circuited. At this time, the pull-up resistors of the access bus 11 are the fifth resistor R5, the sixth resistor R6, the seventh resistor R7, and the eighth resistor R8, because the fifth resistor R5 and the sixth resistor R6 are at this time. The driving voltage of the seventh resistor R7 and the eighth resistor R8 is the voltage of the first power source VSTB1, so that the pull-up voltage formed by the pull-up resistor of the access bus 11 is equal to the pull-up voltage of the slave device 10, and automatic matching of the voltage is achieved.

当比较器 13输出为 0时，锁存器 14在触发信号 M的作用下输出控制信号 0 ,控制第一开关管 Q1和第二开关管 Q2截止，第三开关管 Q3由第 —电源 VSTB1通过第四电阻 R4供电，处于导通状态，使得第五电阻 R5 被短路。此时，接入总线 11的上拉电阻为第三电阻 R3、第六电阻 R6、第七电阻 R7以及第八电阻 R8 ,因为此时第三电阻 R3、第六电阻 R6、第七电阻 R7以及第八电阻 R8的驱动电压为第二电源 VSTB2的电压，因此接入总线 11的上拉电阻形成的上拉电压和从设备 10的上拉电压相等，实现电压的自动匹配。 When the output of the comparator 13 is 0, the latch 14 outputs a control signal 0 under the action of the trigger signal M, and controls the first switching transistor Q1 and the second switching transistor Q2 to be turned off, and the third switching transistor Q3 is passed by the first power supply VSTB1. The fourth resistor R4 is powered, and is in an on state, so that the fifth resistor R5 is short-circuited. At this time, the pull-up resistors of the access bus 11 are the third resistor R3, the sixth resistor R6, the seventh resistor R7, and the eighth resistor R8, because at this time, the third resistor R3, the sixth resistor R6, and the seventh resistor R7 are The driving voltage of the eighth resistor R8 is the voltage of the second power source VSTB2, so the pull-up voltage formed by the pull-up resistor connected to the bus 11 is equal to the pull-up voltage of the slave device 10, and the power is realized. Automatic matching of pressure.

以上是比较器 13和锁存器 14的连接方式属于第一种情况时，比较器 13和锁存器 14的具体工作过程。当比较器 13和锁存器 14的连接方式属于第二种情况时，比较器 13和锁存器 14的具体工作过程如下： The above is the specific operation of the comparator 13 and the latch 14 when the connection mode of the comparator 13 and the latch 14 belong to the first case. When the connection mode of the comparator 13 and the latch 14 belongs to the second case, the specific operation of the comparator 13 and the latch 14 is as follows:

如果比较器 13的第二输入端 132通过总线 11的数据总线 DATA接收从设备 100的上拉电压是和第一电源 VSTB1的上拉电压相等，则该上拉电压大于分压电压，比较器 131输出 0；如果比较器 13的第二输入端 132通过总线 11 的数据总线 DATA 接收从设备 100 的上拉电压是和第二电源 VSTB2的上拉电压相等时，则该上拉电压小于分压电压，比较器 13输出 1。 If the second input terminal 132 of the comparator 13 receives the pull-up voltage of the slave device 100 through the data bus DATA of the bus 11 to be equal to the pull-up voltage of the first power source VSTB1, the pull-up voltage is greater than the divided voltage, and the comparator 131 Output 0; if the second input 132 of the comparator 13 receives the pull-up voltage of the slave device 100 through the data bus DATA of the bus 11 is equal to the pull-up voltage of the second power source VSTB2, then the pull-up voltage is less than the divided voltage The comparator 13 outputs 1.

当比较器 13输出为 0时，锁存器 14在触发信号 M的作用下反相输出端输出控制信号 1 ,控制第一开关管 Q1和第二开关管 Q2导通，第三开关管 Q3截止，使得第三电阻 R3被短路，此时，接入总线 11的上拉电阻为第五电阻 R5、第六电阻 R6、第七电阻 R7以及第八电阻 R8 ,因此接入总线 11的上拉电阻形成的上拉电压和从设备 10的上拉电压相等，实现电压的自动匹配。 When the output of the comparator 13 is 0, the latch 14 outputs the control signal 1 by the inverting output terminal under the action of the trigger signal M, and controls the first switching transistor Q1 and the second switching transistor Q2 to be turned on, and the third switching transistor Q3 is turned off. Therefore, the third resistor R3 is short-circuited. At this time, the pull-up resistors of the access bus 11 are the fifth resistor R5, the sixth resistor R6, the seventh resistor R7, and the eighth resistor R8, so the pull-up resistor of the access bus 11 is connected. The pull-up voltage formed is equal to the pull-up voltage from the device 10 to achieve automatic matching of the voltage.

当比较器 13输出为 1时，锁存器 14在触发信号 M的作用下反相输出端输出控制信号 0 ,控制第一开关管 Q1和第二开关管 Q2截止，第三开关管 Q3由第一电源 VSTB1通过第四电阻 R4供电，处于导通状态，使得第五电阻 R5被短路。此时，接入总线 11的上拉电阻为第三电阻 R3、第六电阻 R6、第七电阻 R7以及第八电阻 R8 ,因为此时第三电阻 R3、第六电阻 R6、第七电阻 R7以及第八电阻 R8的驱动电压为第二电源 VSTB2的电压，因此接入总线 11的上拉电阻形成的上拉电压和从设备 10的上拉电压相等，实现电压的自动匹配。 When the output of the comparator 13 is 1, the latch 14 outputs a control signal 0 at the inverting output terminal under the action of the trigger signal M, and controls the first switching transistor Q1 and the second switching transistor Q2 to be turned off, and the third switching transistor Q3 is turned off. A power source VSTB1 is powered by the fourth resistor R4 and is in an on state, so that the fifth resistor R5 is short-circuited. At this time, the pull-up resistors of the access bus 11 are the third resistor R3, the sixth resistor R6, the seventh resistor R7, and the eighth resistor R8, because at this time, the third resistor R3, the sixth resistor R6, and the seventh resistor R7 are The driving voltage of the eighth resistor R8 is the voltage of the second power source VSTB2, so that the pull-up voltage formed by the pull-up resistor of the access bus 11 is equal to the pull-up voltage of the slave device 10, and automatic matching of the voltage is achieved.

本实施例中，从设备 100的上拉电压值，即第一电源 VSTB1或第二电源 VSTB2的上拉电压值是由主设备 101的类型决定的。例如，当主设备 101 为机架服务器时，从设备 100的上拉电压值为 5V或 3.3V两种。 In the present embodiment, the pull-up voltage value of the slave device 100, i.e., the pull-up voltage value of the first power source VSTB1 or the second power source VSTB2, is determined by the type of the master device 101. For example, when the master device 101 is a rack server, the pull-up voltage value of the slave device 100 is either 5V or 3.3V.

本实施例中，通过分压单元 12对第一电源 VSTB1输出的电压进行分压，以获取分压电压，比较器 13比较分压电压以及从设备 100的上拉电压，并输出比较结果，锁存器 14根据该比较结果控制阻抗单元 15接入总线 11 的上拉电阻的阻值，使得根据从设备的上拉电压调整总线上拉电压的电路 10能自动识别从设备 100的上拉电压（即工作电压），并根据该上拉电压来判断从设备 100的类型，从而自动调整总线 11 的上拉电阻，使得总线 11 的上拉电阻形成的上拉电压与从设备 100的上拉电压相等，从而实现电压匹配。 In this embodiment, the voltage output from the first power supply VSTB1 is divided by the voltage dividing unit 12 to obtain a divided voltage, and the comparator 13 compares the divided voltage and the pull-up voltage of the slave device 100, and outputs a comparison result, the lock The memory 14 controls the resistance of the impedance unit 15 to the pull-up resistor of the bus 11 according to the comparison result, so that the bus pull-up voltage is adjusted according to the pull-up voltage of the slave device. 10 can automatically recognize the pull-up voltage (ie, the operating voltage) of the slave device 100, and determine the type of the slave device 100 according to the pull-up voltage, thereby automatically adjusting the pull-up resistor of the bus 11, so that the pull-up resistor of the bus 11 is formed. The pull-up voltage is equal to the pull-up voltage of the slave device 100 to achieve voltage matching.

进一步的，当识别不同上拉电压的两种以上的从设备时，例如该些从设备是通过扣板或者标准的 PCIE插槽和主设备 101电连接的，或者多种从设备 100是可插拔、 10电源是多样的，或者是与其他需要上拉的总线 11电连接的。根据本发明前述的实施例，只需对应增加比较器 13、锁存器 14以及阻抗单元 15的数量即可，其工作原理与前文所述的相同，在此不再赘述。 Further, when two or more slave devices of different pull-up voltages are identified, for example, the slave devices are electrically connected to the master device 101 through a gusset or a standard PCIE slot, or the plurality of slave devices 100 are pluggable. The pull-out, 10 power supplies are various, or are electrically connected to other buses 11 that need to be pulled up. According to the foregoing embodiment of the present invention, the number of the comparator 13, the latch 14, and the impedance unit 15 need to be increased correspondingly, and the working principle is the same as that described above, and details are not described herein again.

本发明实施例还提供了一种根据从设备的上拉电压调整总线上拉电压的方法的流程图。其是在前述实施例的一种根据从设备的上拉电压调整总线上拉电压的电路 10的基础上进行详细描述。请参阅图 3 ,根据从设备的上拉电压调整总线上拉电压的方法包括以下步骤： Embodiments of the present invention also provide a flowchart of a method for adjusting a bus pull-up voltage according to a pull-up voltage of a slave device. It is described in detail based on a circuit 10 for adjusting the pull voltage on the bus line in accordance with the pull-up voltage of the slave device of the foregoing embodiment. Referring to Figure 3, the method of adjusting the bus pull-up voltage according to the pull-up voltage of the slave device includes the following steps:

步骤 S1：对第一电源 VSTB1输出的电压进行分压，以获取分压电压。在对第一电源 VSTB1输出的电压进行分压前，首先需要确定第一电压源 VSTB1的电压值。具体而言，首先确定主设备 101和连接方式类型，例如扣板或标准的 PCIE插槽，然后根据连接方式的类型确定使用该连接方式与主设备 101电连接的多种从设备 100 ,包括确定该些从设备 100中的上拉例进行说明。 Step S1: The voltage output from the first power source VSTB1 is divided to obtain a divided voltage. Before the voltage output from the first power source VSTB1 is divided, it is first necessary to determine the voltage value of the first voltage source VSTB1. Specifically, the master device 101 and the connection mode type, such as a stencil or a standard PCIE slot, are first determined, and then the plurality of slave devices 100 electrically connected to the master device 101 using the connection manner are determined according to the type of the connection manner, including determining The pull-up examples in the slave device 100 will be described.

当确定不同上拉电压的两种从设备 100后，将和两种从设备 100中的最大上拉电压相等的电源设定为第一电源 VSTB1 ,将和另一从设备 100的上拉电压相等的电源设定为第二电源 VSTB2。即第一电源 VSTB1是同一类型的连接方式对应的多种从设备中上拉电压值最大的电源。第二电源 VSTB2对应的从设备和第一电源 VSTB1 对应的从设备是同一类型的连接方式中的两种从设备，并且第二电源 VSTB2 的上拉电压小于第一电源 VSTB1的上拉电压。 When two slave devices 100 of different pull-up voltages are determined, a power source equal to the maximum pull-up voltages of the two slave devices 100 is set as the first power source VSTB1, which is equal to the pull-up voltage of the other slave device 100. The power supply is set to the second power supply VSTB2. That is, the first power source VSTB1 is the power source having the largest pull-up voltage value among the plurality of slave devices corresponding to the same type of connection method. The slave device corresponding to the second power source VSTB2 and the slave device corresponding to the first power source VSTB1 are two slave devices of the same type of connection mode, and the pull-up voltage of the second power source VSTB2 is smaller than the pull-up voltage of the first power source VSTB1.

进一步地，对第一电源 VSTB1输出的电压进行分压后获取的分压电压大于第二电源 VSTB2的上拉电压，并小于第一电源 VSTB1的上拉电压。 Further, the divided voltage obtained by dividing the voltage output from the first power source VSTB1 is larger than the pull-up voltage of the second power source VSTB2, and smaller than the pull-up voltage of the first power source VSTB1.

步骤 S2：比较分压电压和从设备的上拉电压的大小，并输出比较结果。比较结果有以下两种情况： Step S2: Compare the magnitude of the divided voltage and the pull-up voltage of the slave device, and output the comparison result. There are two cases of comparison results:

第一种情况：当分压电压大于从设备 100的上拉电压时，比较结果为 0 , 当分压电压小于从设备 100的上拉电压时，比较结果为 1； The first case: when the divided voltage is greater than the pull-up voltage of the slave device 100, the comparison result is 0, and when the divided voltage is less than the pull-up voltage of the slave device 100, the comparison result is 1;

第二种情况：当分压电压大于从设备 100的上拉电压时，比较结果为 1 , 当分压电压小于从设备 100的上拉电压时，比较结果为 0。 The second case: when the divided voltage is greater than the pull-up voltage of the slave device 100, the comparison result is 1 , and when the divided voltage is less than the pull-up voltage of the slave device 100, the comparison result is 0.

步骤 S3：根据比较结果输出控制信号控制接入总线的上拉电阻的阻值，使得总线的上拉电阻形成的上拉电压与从设备内的上拉电压相等，实现电压匹配。 Step S3: The output control signal is controlled according to the comparison result to control the resistance of the pull-up resistor of the access bus, so that the pull-up voltage formed by the pull-up resistor of the bus is equal to the pull-up voltage in the slave device to achieve voltage matching.

由前文可知，本实施例确定的两种从设备 100的上拉电压分别和第一电源 VSTB1的上拉电压和第二电源 VSTB2的上拉电压相等。 As can be seen from the foregoing, the pull-up voltages of the two slave devices 100 determined in this embodiment are equal to the pull-up voltage of the first power source VSTB1 and the pull-up voltage of the second power source VSTB2, respectively.

当比较结果为第一种情况时，具体为： When the comparison result is the first case, it is specifically:

当比较结果为 1时，说明该从设备 100的上拉电压和第一电源 VSTB1 的上拉电压相等，则输出控制信号 1 ,以控制上拉电阻形成的上拉电压与第一电源 VSTB1的上拉电压相等； When the comparison result is 1, it indicates that the pull-up voltage of the slave device 100 and the pull-up voltage of the first power source VSTB1 are equal, and the control signal 1 is output to control the pull-up voltage formed by the pull-up resistor and the first power source VSTB1. Pulling voltages are equal;

当比较结果为 0时，说明该从设备 100的上拉电压和第二电源 VSTB2 的上拉电压相等，则输出控制信号 0 ,以控制上拉电阻形成的上拉电压与第二电源 VSTB2的上拉电压相等。 When the comparison result is 0, indicating that the pull-up voltage of the slave device 100 and the pull-up voltage of the second power source VSTB2 are equal, the control signal 0 is output to control the pull-up voltage formed by the pull-up resistor and the second power source VSTB2. The pull voltages are equal.

当比较结果为第二种情况时，具体为： When the comparison result is the second case, it is specifically:

当比较结果为 1时，说明该从设备 100的上拉电压和第二电源 VSTB2 的上拉电压相等，则输出控制信号 0 ,以控制上拉电阻形成的上拉电压与第二电源 VSTB2的上拉电压相等； When the comparison result is 1, it indicates that the pull-up voltage of the slave device 100 and the pull-up voltage of the second power source VSTB2 are equal, and the control signal 0 is output to control the pull-up voltage formed by the pull-up resistor and the second power source VSTB2. Pulling voltages are equal;

当比较结果为 0时，说明该从设备 100的上拉电压和第一电源 VSTB1 的上拉电压相等，则输出控制信号 1 ,以控制上拉电阻形成的上拉电压与所述第一电源 VSTB1的上拉电压相等。 When the comparison result is 0, indicating that the pull-up voltage of the slave device 100 and the pull-up voltage of the first power source VSTB1 are equal, the control signal 1 is output to control the pull-up voltage formed by the pull-up resistor and the first power source VSTB1. The pull-up voltages are equal.

具体控制上拉电阻形成上拉电压的原理如前文所述，在此不再赘述。综上所述，本发明通过分压单元 12对第一电源 VSTB1输出的电压进行分压，以获取分压电压，比较器 13比较分压电压以及从设备 100的上拉电压，并输出比较结果，锁存器 14根据该比较结果控制阻抗单元 15接入总线 11的上拉电阻的阻值，使得根据从设备的上拉电压调整总线上拉电压的电路 10能自动识别从设备 100的上拉电压（即工作电压），并根据该上拉电压来判断从设备 100的类型，从而自动调整总线 11的上拉电阻，使得总线 11的上拉电阻形成的上拉电压与从设备 100的上拉电压相等，从而实现电压匹配。 The principle of specifically controlling the pull-up resistor to form the pull-up voltage is as described above, and will not be described herein. In summary, the present invention divides the voltage output from the first power supply VSTB1 by the voltage dividing unit 12 to obtain a divided voltage, and the comparator 13 compares the divided voltage and the pull-up voltage of the slave device 100, and outputs a comparison result. The latch 14 controls the resistance of the impedance unit 15 to the pull-up resistor of the bus 11 according to the comparison result, so that the circuit 10 for adjusting the bus pull-up voltage according to the pull-up voltage of the slave device can automatically recognize the pull-up of the slave device 100. Voltage (ie operating voltage) and according to the upper The voltage is pulled to judge the type of the slave device 100, thereby automatically adjusting the pull-up resistance of the bus 11, so that the pull-up voltage formed by the pull-up resistor of the bus 11 is equal to the pull-up voltage of the slave device 100, thereby achieving voltage matching.

以上所述仅为本发明的实施例，并非因此限制本发明的专利范围，凡是利用本发明说明书及附图内容所作的等效结构或等效流程变换，或直接或间接运用在其他相关的技术领域，均同理包括在本发明的专利保护范围 The above is only the embodiment of the present invention, and is not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformation of the present invention and the contents of the drawings may be directly or indirectly applied to other related technologies. The scope of the patent protection is included in the scope of patent protection of the present invention.

Claims

权利要求 Rights request

1. 一种根据从设备的上拉电压调整总线上拉电压的电路，其特征在于，所述电路包括总线、分压单元、比较器、锁存器以及阻抗单元，所述总线与所述从设备电连接，其中： 1. A circuit for adjusting the bus pull-up voltage according to the pull-up voltage of the slave device, characterized in that the circuit includes a bus, a voltage dividing unit, a comparator, a latch and an impedance unit, and the bus is connected to the slave device. Equipment is electrically connected, where:

所述分压单元对第一电源输出的电压进行分压，以获取分压电压，所述第一电源是同一类型的连接方式对应的多种所述从设备中上拉电压值最大的电源； The voltage dividing unit divides the voltage output by the first power supply to obtain the divided voltage. The first power supply is the power supply with the largest pull-up voltage value among the multiple slave devices corresponding to the same type of connection method;

所述比较器的第一输入端接收所述分压电压，所述比较器的第二输入端通过所述总线接收所述从设备的上拉电压，所述比较器的输出端输出比较结果； The first input terminal of the comparator receives the divided voltage, the second input terminal of the comparator receives the pull-up voltage of the slave device through the bus, and the output terminal of the comparator outputs a comparison result;

所述锁存器的第一输入端接收所述比较结果，所述锁存器的第二输入端接收一触发信号，所述锁存器的输出端输出控制信号控制所述阻抗单元接入所述总线的上拉电阻的阻值，使得所述总线的上拉电阻形成的上拉电压与所述从设备的上拉电压相等，实现电压匹配。 The first input terminal of the latch receives the comparison result, the second input terminal of the latch receives a trigger signal, and the output terminal of the latch outputs a control signal to control the access of the impedance unit. The resistance of the pull-up resistor of the bus is such that the pull-up voltage formed by the pull-up resistor of the bus is equal to the pull-up voltage of the slave device to achieve voltage matching.

2. 根据权利要求 1所述的电路，其特征在于，所述分压电路包括第一电阻和第二电阻，所述第一电阻的一端连接所述第一电源，所述第一电阻的另一端连接所述第二电阻的一端和所述比较器的第一输入端，所述第二电阻的第二端接地。 2. The circuit according to claim 1, wherein the voltage dividing circuit includes a first resistor and a second resistor, one end of the first resistor is connected to the first power supply, and the other end of the first resistor is connected to the first power supply. One end is connected to one end of the second resistor and the first input end of the comparator, and the second end of the second resistor is connected to ground.

3. 根据权利要求 2所述的电路，其特征在于，所述比较器的第一输入端为负向输入端，所述比较器的第二输入端为正向输入端，所述锁存器的输出端为同相输出端。 3. The circuit according to claim 2, wherein the first input terminal of the comparator is a negative input terminal, the second input terminal of the comparator is a positive input terminal, and the latch The output terminal is a non-inverting output terminal.

4. 根据权利要求 2所述的电路，其特征在于，所述比较器的第一输入端为正向输入端，所述比较器的第二输入端为负向输入端，所述锁存器的输出端为反相输出端。 4. The circuit of claim 2, wherein the first input terminal of the comparator is a positive input terminal, the second input terminal of the comparator is a negative input terminal, and the latch The output terminal is the inverting output terminal.

5. 根据权利要求 3或 4任一项所述的电路，其特征在于，所述总线包括数据总线和时钟总线，所述阻抗单元包括第一开关管、第二开关管、第三开关管、第三电阻、第四电阻、第五电阻、第六电阻、第七电阻以及第八电阻，其中，所述锁存器的输出端连接所述第一开关管的棚极和所述第二开关管的棚极，所述第二开关管的源极接地，所述第二开关管的漏极连接所述第三电阻的一端，所述第三电阻的另一端连接一第二电源，所述第一开关管的源极接地，所述第一开关管的漏极连接所述第四电阻的一端以及所述第三开关管的棚极，所述第四电阻的另一端连接所述第五电阻的一端以及所述第一电源，所述第五电阻的另一端连接所述第三开关管的漏极、所述第六电阻和所述第七电阻的一端，所述第三开关管的源极接地，所述第六电阻的另一端连接所述时钟总线，所述第七电阻的另一端连接所述第八电阻的一端以及所述第二开关管的漏极，所述第八电阻的另一端连接所述数据总线，其中，所述第二电源对应的所述从设备和所述第一电源对应的所述从设备是同一类型的连接方式中的两种从设备，并且所述第二电源的上拉电压小于所述第一电源的上拉电压。 5. The circuit according to claim 3 or 4, wherein the bus includes a data bus and a clock bus, and the impedance unit includes a first switch tube, a second switch tube, a third switch tube, The third resistor, the fourth resistor, the fifth resistor, the sixth resistor, the seventh resistor and the eighth resistor, wherein the output end of the latch is connected to the gate electrode of the first switch tube and the second switch The gate electrode of the tube, the source of the second switch tube is grounded, the drain of the second switch tube is connected to one end of the third resistor, and the other end of the third resistor is connected to a second power supply. No. The source electrode of a switch tube is grounded, the drain electrode of the first switch tube is connected to one end of the fourth resistor and the shed electrode of the third switch tube, and the other end of the fourth resistor is connected to the fifth resistor. One end of the fifth resistor and the first power supply, the other end of the fifth resistor is connected to the drain of the third switch tube, one end of the sixth resistor and the seventh resistor, and the source of the third switch tube The other end of the sixth resistor is connected to the clock bus, the other end of the seventh resistor is connected to one end of the eighth resistor and the drain of the second switch tube, and the other end of the eighth resistor is connected to the ground. The other end is connected to the data bus, wherein the slave device corresponding to the second power supply and the slave device corresponding to the first power supply are two slave devices in the same type of connection mode, and the third power supply is connected to the data bus. The pull-up voltage of the second power supply is smaller than the pull-up voltage of the first power supply.

6. 根据权利要求 5所述的电路，其特征在于，所述从设备通过所述总线电连接一主设备，所述电路还包括第三电源、第四开关管和第五开关管，所述第四开关管设置在所述数据总线上，所述第五开关管设置在所述时钟总线上，所述第四开关管和所述第五开关管的棚极接收所述第三电源输出的电压，所述第四开关管和所述第五开关管的源极电连接所述主设备，所述第四开关管和所述第五开关管的漏极电连接所述从设备。 6. The circuit according to claim 5, wherein the slave device is electrically connected to a master device through the bus, and the circuit further includes a third power supply, a fourth switch tube and a fifth switch tube, The fourth switch tube is arranged on the data bus, and the fifth switch tube is arranged on the clock bus. The gate electrodes of the fourth switch tube and the fifth switch tube receive the output of the third power supply. voltage, the sources of the fourth switching tube and the fifth switching tube are electrically connected to the master device, and the drains of the fourth switching tube and the fifth switching tube are electrically connected to the slave device.

7. 根据权利要求 6所示的电路，其特征在于，所述电路还包括第四电源、第九电阻和第十电阻，所述第九电阻和所述第十电阻的一端接收所述第四电源输出的电压，所述第九电阻和第十电阻的另一端分别电连接所述数据总线和时钟总线。 7. The circuit according to claim 6, characterized in that the circuit further includes a fourth power supply, a ninth resistor and a tenth resistor, one end of the ninth resistor and the tenth resistor receives the fourth The voltage output by the power supply, the other ends of the ninth resistor and the tenth resistor are electrically connected to the data bus and the clock bus respectively.

8. 根据权利要求 7所述的电路，其特征在于，所述比较器还包括电源端和接地端，所述电源端接收所述第一电源电压，所述接地端接地。 8. The circuit according to claim 7, wherein the comparator further includes a power supply terminal and a ground terminal, the power supply terminal receives the first power supply voltage, and the ground terminal is connected to ground.

9. 根据权利要求 5所述的电路，其特征在于，所述分压电压大于所述第二电源的上拉电压，并小于所述第一电源的上拉电压。 9. The circuit of claim 5, wherein the divided voltage is greater than the pull-up voltage of the second power supply and less than the pull-up voltage of the first power supply.

10. 一种根据从设备的上拉电压调整总线上拉电压的方法，其特征在于，所述方法包括以下步骤： 10. A method for adjusting the bus pull-up voltage according to the pull-up voltage of the slave device, characterized in that the method includes the following steps:

对所述第一电源输出的电压进行分压，以获取分压电压，其中，所述第一电源是同一类型的连接方式对应的多种所述从设备中上拉电压值最大的电源； Divide the voltage output by the first power supply to obtain the divided voltage, wherein the first power supply is the power supply with the largest pull-up voltage value among multiple slave devices corresponding to the same type of connection mode;

比较所述分压电压和所述从设备的上拉电压的大小，并输出比较结果；根据所述比较结果输出控制信号控制接入总线的上拉电阻的阻值，使得所述总线的上拉电阻形成的上拉电压与所述从设备的上拉电压相等，实现电压匹配，其中，所述总线与所述从设备电连接。 Compare the divided voltage and the pull-up voltage of the slave device, and output the comparison result; output a control signal according to the comparison result to control the resistance of the pull-up resistor connected to the bus, so that The pull-up voltage formed by the pull-up resistor of the bus is equal to the pull-up voltage of the slave device to achieve voltage matching, wherein the bus is electrically connected to the slave device.

11. 根据权利要求 10所述的方法，其特征在于，所述对所述第一电源输出的电压进行分压，以获取分压电压的步骤进一步包括： 11. The method according to claim 10, wherein the step of dividing the voltage output by the first power supply to obtain the divided voltage further includes:

对所述第一电源输出的电压进行分压后获取的分压电压大于第二电源的上拉电压，并小于所述第一电源的上拉电压； The divided voltage obtained after dividing the voltage output by the first power supply is greater than the pull-up voltage of the second power supply and less than the pull-up voltage of the first power supply;

其中，所述第二电源对应的所述从设备和所述第一电源对应的所述从设备是同一类型的连接方式中的两种从设备，并且所述第二电源的上拉电压小于所述第一电源的上拉电压。 Wherein, the slave device corresponding to the second power supply and the slave device corresponding to the first power supply are two slave devices in the same type of connection mode, and the pull-up voltage of the second power supply is less than the The pull-up voltage of the first power supply.

12. 根据权利要求 11所述的方法，其特征在于，其中，所述比较所述分压电压和所述从设备的上拉电压的大小，并输出比较结果的步骤进一步包括： 12. The method according to claim 11, wherein the step of comparing the divided voltage and the pull-up voltage of the slave device, and outputting the comparison result further includes:

当所述分压电压大于所述从设备的上拉电压时，所述比较结果为 0；当所述分压电压小于所述从设备的上拉电压时，所述比较结果为 1。 When the divided voltage is greater than the pull-up voltage of the slave device, the comparison result is 0; when the divided voltage is less than the pull-up voltage of the slave device, the comparison result is 1.

13. 根据权利要求 12所述的方法，其特征在于，所述根据所述比较结果输出控制信号的步骤进一步包括： 13. The method of claim 12, wherein the step of outputting a control signal according to the comparison result further includes:

当所述比较结果为 1时，输出控制信号 1； When the comparison result is 1, the control signal 1 is output;

当所述比较结果为 0时，输出控制信号 0。 When the comparison result is 0, the control signal 0 is output.

14. 根据权利要求 11所述的方法，其特征在于，所述比较所述分压电压和所述从设备的上拉电压的大小，并输出比较结果的步骤进一步包括：当所述分压电压大于所述从设备的上拉电压时，所述比较结果为 1；当所述分压电压小于所述从设备的上拉电压时，所述比较结果为 0。 14. The method of claim 11, wherein the step of comparing the divided voltage with the pull-up voltage of the slave device and outputting the comparison result further includes: when the divided voltage When the divided voltage is greater than the pull-up voltage of the slave device, the comparison result is 1; when the divided voltage is less than the pull-up voltage of the slave device, the comparison result is 0.

15. 根据权利要求 14所述的方法，其特征在于，所述根据所述比较结果输出控制信号的步骤进一步包括： 15. The method of claim 14, wherein the step of outputting a control signal according to the comparison result further includes:

当所述比较结果为 1时，输出控制信号 0； When the comparison result is 1, the control signal 0 is output;

当所述比较结果为 0时，输出控制信号 1。 When the comparison result is 0, the control signal 1 is output.