CN210609085U

CN210609085U - Microcontroller for temperature compensation quartz crystal oscillator

Info

Publication number: CN210609085U
Application number: CN201921998220.2U
Authority: CN
Inventors: 俞小平; 黄坚; 胡依婷; 李良
Original assignee: Wuxi I Core Electronics Co ltd
Current assignee: Wuxi I Core Electronics Co ltd
Priority date: 2019-11-19
Filing date: 2019-11-19
Publication date: 2020-05-22
Anticipated expiration: 2029-11-19

Abstract

The utility model discloses a belong to microcontroller technical field, specifically be a microcontroller for temperature compensation quartz crystal oscillator, including microcontroller and clock circuit, microcontroller's inside includes stabiliser, temperature sensor, AD converter, treater, memory, PWM pulse width modulation unit, second order passive filter, this kind of microcontroller for temperature compensation quartz crystal oscillator, clock circuit and quartz crystal form the oscillator, and clock circuit's control voltage terminal is by microcontroller control, can send different PWM frequency through microcontroller, change varactor's junction capacitance value, and then reach adjustment crystal oscillation frequency, change the thinking that adopts discrete device to realize, through integrating stabiliser, temperature sensor, PWM second order filter circuit in microcontroller, can effectively reduce crystal oscillator whole volume, the real-time performance of temperature sensing is improved, the cost is reduced, and the reliability is high.

Description

Microcontroller for temperature compensation quartz crystal oscillator

Technical Field

The utility model relates to a microcontroller technical field specifically is a microcontroller for warm-patch quartz crystal oscillator.

Background

The quartz crystal oscillator, also called quartz resonator, crystal oscillator for short, is made of quartz crystal wafer with piezoelectric effect. When the frequency of the alternating electric field is the same as the natural frequency of the quartz crystal, the vibration becomes very strong, which is the reaction of the resonance characteristic of the crystal. The crystal oscillator has the advantages of small volume, light weight, high reliability, high frequency stability and the like, and is applied to household appliances and communication equipment.

In most applications, quartz crystal resonators have the advantage of providing a temperature stable frequency (with variations on the order of 0.5 ppm/deg.C) over the usual temperature range, however, in some applications, this accuracy does not seem sufficient.

At present, the control part of a temperature compensation quartz crystal oscillator is completed by a plurality of single-function chips, a 5V power supply is stabilized to 3V by a voltage stabilizer to supply power to a thermometer sensor and a clock circuit, and the rest is directly supplied with power by an external 5V power supply. After the 5V power is electrified, temperature sensor response ambient temperature, with signal feedback to microcontroller, clock circuit and quartz crystal combine to produce clock signal, and microcontroller control clock circuit adjusts quartz crystal output clock signal frequency, adopts this kind of mode, needs on a plurality of chips, a lot of resistance-capacitance electronic component pasted dress PCB board, and not only the cost is higher, occupies comparatively many PCB area moreover, bulky, and performance stability is poor.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a microcontroller for temperature compensation quartz crystal oscillator to solve the current that proposes in the above-mentioned background art, temperature compensation quartz crystal oscillator's control part is accomplished by the chip of a plurality of single functions, and the 5V power supplies power for thermometer sensor and clock circuit through stabiliser steady voltage to 3V, all the other direct power supplies by outside 5V power. After the 5V power is electrified, temperature sensor response ambient temperature, with signal feedback to microcontroller, clock circuit and quartz crystal combine to produce clock signal, and microcontroller control clock circuit adjusts quartz crystal output clock signal frequency, adopts this kind of mode, needs on a plurality of chips, a lot of resistance-capacitance electronic component pasted dress PCB board, and not only the cost is higher, occupies more PCB area moreover, bulky, the poor problem of performance stability.

In order to achieve the above object, the utility model provides a following technical scheme: a microcontroller for a temperature compensated quartz crystal oscillator comprises a microcontroller and a clock circuit, wherein the microcontroller comprises a voltage stabilizer, a temperature sensor, an AD converter, a processor, a memory, a PWM (pulse width modulation) unit and a second-order passive filter, the electrical output end of the voltage stabilizer is electrically connected with the temperature sensor and the power input end of the clock circuit, the electrical output end of the temperature sensor is electrically connected with the electrical input end of the AD converter, the electrical output end of the AD converter is electrically connected with the electrical input end of the processor, the electrical output end of the processor is electrically connected with the temperature sensor, the memory and the electrical input end of the PWM unit, the electrical output end of the PWM unit is electrically connected with the second-order passive filter, and the electrical output end of the second-order passive filter is electrically connected with the electrical input end of the clock circuit, and the left side wall of the clock circuit is electrically connected with a quartz crystal.

Preferably, the clock circuit internally comprises a varactor diode, and an electrical output end of the second-order passive filter is electrically connected with a control end of the varactor diode.

Preferably, the memory is a FLASH memory.

Preferably, the clock circuit includes an inverter, a feedback resistor, a load capacitor, a varactor, an isolation resistor, and a control voltage terminal, and the inverter and the feedback resistor form an inverting amplifier.

Preferably, the voltage stabilizer is a 5V power supply through voltage stabilizer.

Preferably, an electrical input terminal of the clock circuit is electrically connected to an electrical output terminal of the control voltage terminal.

Preferably, the electrical input terminal of the control voltage terminal is electrically connected with the electrical output terminal of the microcontroller.

Preferably, the output end of the microcontroller sends different PWM frequencies and is electrically connected to the varactor diode.

Compared with the prior art, the beneficial effects of the utility model are that: this kind of a microcontroller for temperature compensation quartz crystal oscillator, clock circuit and quartz crystal have formed the oscillator, and clock circuit's control voltage terminal is by microcontroller control, different PWM frequency is sent to the accessible microcontroller, change varactor's junction capacitance value, and then reach adjustment crystal oscillation frequency, the thinking that the change adopted discrete device to realize, through with the stabiliser, temperature sensor, PWM second order filter circuit is integrated to microcontroller in, can effectively reduce crystal oscillator overall size, improve the real-time of temperature-sensing, reduce cost, high reliability.

Drawings

Fig. 1 is a schematic diagram of a prior art quartz crystal oscillator for realizing full temperature compensation according to the present invention;

FIG. 2 is a schematic diagram of the temperature compensated quartz crystal oscillator circuit of the present invention;

fig. 3 is a schematic diagram of the clock circuit according to the present invention.

In the figure: 100 microcontroller, 110 voltage stabilizer, 120 temperature sensor, 130AD converter, 140 processor, 150 memory, 160PWM pulse width modulation unit, 170 second-order passive filter, 200 clock circuit, 210 quartz crystal.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

The utility model provides a microcontroller for temperature compensation quartz crystal oscillator, which has small volume, low cost and high reliability through the combined application of accessories, please refer to fig. 1-3, comprising a microcontroller 100 and a clock circuit 200;

referring to fig. 2 again, the output terminal of the microcontroller 100 is fixedly connected to the input terminal of the clock circuit 200, specifically, the microcontroller 100 includes a voltage regulator 110, a temperature sensor 120, an AD converter 130, a processor 140, a memory 150, a PWM pulse width modulation unit 160, and a second-order passive filter 170, the electrical output terminal of the voltage regulator 110 is electrically connected to the temperature sensor 120 and the power input terminal of the clock circuit 200, the electrical output terminal of the temperature sensor 120 is electrically connected to the electrical input terminal of the AD converter 130, the electrical output terminal of the AD converter 130 is electrically connected to the electrical input terminal of the processor 140, the electrical output terminal of the processor 140 is electrically connected to the temperature sensor 120, the memory 150, and the electrical input terminal of the PWM pulse width modulation unit 160, the electrical output terminal of the PWM pulse width modulation unit 160 is electrically connected to the second-order passive filter 170, the electrical output terminal of the second-order passive filter 170 is electrically, the left side wall of the clock circuit 200 is electrically connected with a quartz crystal 210;

in a specific use, first the microcontroller 100 comprises: the voltage stabilizer 110, the temperature sensor 120, the AD converter 130, the processor 140, the memory 150, the PWM pulse width modulation unit 160, the second-order passive filter circuit 170, the voltage stabilizer 110 stabilizes the external power supply 5V to 3V, supplies power to the internal temperature sensor 120 and the external clock circuit 200, the temperature sensor 120 senses the temperature, converts the temperature value into an analog voltage signal and sends the analog voltage signal to the AD converter 130, the AD converter 130 converts the received analog voltage signal into a digital quantity and sends the digital quantity to the processor 140, the processor 140 reads the data stored in the memory 150 according to the received digital quantity and controls and adjusts the output frequency duty ratio of the PWM pulse width modulation unit according to the read data, the output of the PWM pulse width modulation unit 160 is sent to the second-order passive filter 170, the second-order passive filter 170 converts a periodic signal into an analog voltage signal and sends the analog voltage signal to the control end of the, the junction capacitance value of the variable capacitance diode is changed by adjusting the voltage value of the variable capacitance diode, so that the output frequency of the crystal oscillator is adjusted.

Referring again to fig. 2, in order to store data and facilitate digital quantity reading, the memory 150 is specifically a FLASH memory.

Referring to fig. 2 again, the inverter and the feedback resistor form an inverting amplifier, and the capacitor prevents the control voltage terminal of the varactor diode from affecting the crystal oscillation by using the dc blocking function of the capacitor, specifically, the clock circuit 200 includes an inverter, a feedback resistor, a load capacitor, a varactor diode, an isolation resistor, and a control voltage terminal, and the inverter and the feedback resistor form an inverting amplifier.

Referring to fig. 2 again, to facilitate the voltage stabilization process, the voltage regulator 110 is a 5V power supply.

Referring to fig. 2 again, in order to change the junction capacitance of the varactor diode by the microcontroller 100 sending different PWM frequencies, specifically, the electrical input terminal of the clock circuit 200 is electrically connected to the electrical output terminal of the control voltage terminal, and the electrical input terminal of the control voltage terminal is electrically connected to the electrical output terminal of the microcontroller 100.

Referring again to fig. 2, in order to adjust the oscillation frequency of the crystal, specifically, the output terminal of the microcontroller 100 sends different PWM frequencies and is electrically connected to the varactor diode.

While the invention has been described above with reference to an embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, as long as there is no structural conflict, the various features of the disclosed embodiments of the present invention can be used in any combination with each other, and the description of such combinations is not exhaustive in the present specification only for the sake of brevity and resource conservation. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

1. A microcontroller for a temperature compensated quartz crystal oscillator, comprising: the intelligent temperature control system comprises a microcontroller (100) and a clock circuit (200), wherein the microcontroller (100) internally comprises a voltage stabilizer (110), a temperature sensor (120), an AD converter (130), a processor (140), a memory (150), a PWM (pulse width modulation) unit (160) and a second-order passive filter (170), the electrical output end of the voltage stabilizer (110) is electrically connected with the temperature sensor (120) and the power input end of the clock circuit (200), the electrical output end of the temperature sensor (120) is electrically connected with the electrical input end of the AD converter (130), the electrical output end of the AD converter (130) is electrically connected with the electrical input end of the processor (140), and the electrical output end of the processor (140) is electrically connected with the electrical input ends of the temperature sensor (120), the memory (150) and the PWM (160), the electrical output end of the PWM unit (160) is electrically connected with the second-order passive filter (170), the electrical output end of the second-order passive filter (170) is electrically connected with the electrical input end of the clock circuit (200), and the left side wall of the clock circuit (200) is electrically connected with a quartz crystal (210).

2. The microcontroller for a temperature compensated quartz crystal oscillator according to claim 1, wherein: the clock circuit (200) internally comprises a variable capacitance diode, and the electrical output end of the second-order passive filter (170) is electrically connected with the control end of the variable capacitance diode.

3. The microcontroller for a temperature compensated quartz crystal oscillator according to claim 1, wherein: the memory (150) is a FLASH memory.

4. The microcontroller for a temperature compensated quartz crystal oscillator according to claim 1, wherein: the clock circuit (200) comprises an inverter, a feedback resistor, a load capacitor, a variable capacitance diode, an isolation resistor and a control voltage terminal, wherein the inverter and the feedback resistor form an inverting amplifier.

5. The microcontroller for a temperature compensated quartz crystal oscillator according to claim 1, wherein: the voltage stabilizer (110) is a 5V power supply through a voltage stabilizer.

6. The microcontroller for a temperature-compensated quartz crystal oscillator according to claim 4, characterized in that: the electrical input end of the clock circuit (200) is electrically connected with the electrical output end of the control voltage terminal.

7. The microcontroller for a temperature-compensated quartz crystal oscillator according to claim 6, characterized in that: the electrical input end of the control voltage terminal is electrically connected with the electrical output end of the microcontroller (100).

8. The microcontroller for a temperature compensated quartz crystal oscillator according to claim 2, wherein: the output end of the microcontroller (100) sends different PWM frequencies and is electrically connected with the variable capacitance diode.