CN214338164U

CN214338164U - LED brightness adjusting circuit and electronic equipment

Info

Publication number: CN214338164U
Application number: CN202120052358.4U
Authority: CN
Inventors: 郭世文; 彭久高; 吴海全
Original assignee: Shenzhen Grandsun Electronics Co Ltd
Current assignee: Shenzhen Grandsun Electronics Co Ltd
Priority date: 2021-01-08
Filing date: 2021-01-08
Publication date: 2021-10-01
Anticipated expiration: 2031-01-08

Abstract

The application relates to an LED brightness adjusting circuit and an electronic device, wherein the LED brightness adjusting circuit comprises a power supply conversion circuit, a control circuit, an LED assembly and an LED control circuit, and the control circuit outputs an enable signal and a control signal; when the power supply conversion circuit is connected with the power supply voltage, the power supply conversion circuit converts the power supply voltage into a stabilized direct current according to the enabling signal; the LED component is lightened according to the voltage-stabilizing direct current; the LED control circuit communicates the regulated direct current to a power ground according to the control signal to control the lighting of the LED assembly. The LED component keeps the consistency of brightness, and the stability and the uniformity of the luminous brightness of the LED component are improved.

Description

LED brightness adjusting circuit and electronic equipment

Technical Field

The application relates to the technical field of LED brightness adjustment, in particular to an LED brightness adjusting circuit and electronic equipment.

Background

With the development of science and technology, the variety of electronic products is increasing nowadays, and the functions of the electronic products are also increasing. For example, a bluetooth headset is one of the widely used electronic products. The bluetooth headset is a wireless communication device that applies bluetooth technology to hands-free headsets, so that users can avoid annoying wire stumbling and can easily talk in various ways. Bluetooth headsets are typically provided with LED lights that can be used to indicate bluetooth headset connection status, etc. Currently, the LED light portion of existing bluetooth headsets is directly powered by a battery.

In the implementation process, the inventor finds that at least the following problems exist in the conventional technology: in the traditional Bluetooth headset LED part is directly powered by a battery, the input voltage of the LED lamp is suddenly high or suddenly low due to the fact that the battery power is reduced along with the power consumption of the system, the brightness is uneven and inconsistent, and the user experience effect is influenced.

SUMMERY OF THE UTILITY MODEL

Therefore, the LED brightness adjusting circuit and the electronic device thereof are needed to solve the problems of high and low input voltage, uneven brightness and inconsistency of an LED lamp caused by the fact that the LED part of the traditional Bluetooth headset is directly powered by a battery.

In order to achieve the above object, in one aspect, an embodiment of the present application provides an LED brightness adjusting circuit, further including:

the control circuit is connected with the power conversion circuit and the LED control circuit and is configured to output an enable signal and a control signal;

the power supply conversion circuit is configured to convert the power supply voltage into a stabilized direct current according to the enabling signal when the power supply voltage is accessed;

an LED component configured to be lit according to a regulated direct current;

and the LED control circuit is connected with the LED assembly and the power ground and is configured to communicate the regulated direct current to the power ground according to a control signal so as to control the lighting of the LED assembly.

In one embodiment, the method further comprises the following steps:

and the first current limiting circuit is connected with the power conversion circuit and the LED assembly and is configured to limit the regulated direct current.

In one embodiment, the method further comprises the following steps:

and the second current limiting circuit is connected with the LED control circuit and the LED assembly and is configured to limit the stabilized direct current.

In one embodiment, the LED control circuit comprises a plurality of field effect transistors;

the drain electrodes of the field effect tubes are connected to the voltage-stabilizing direct current input end of the LED control circuit, the source electrodes of the field effect tubes are connected to the voltage-stabilizing direct current output end of the LED control circuit, and the grid electrodes of the field effect tubes are connected to the control signal input end of the LED control circuit.

In one embodiment, the device further comprises a plurality of pull-down resistors;

the first ends of the pull-down resistors are respectively connected with the grids of the field effect transistors, and the second ends of the pull-down resistors are commonly connected with the power ground.

In one embodiment, the LED assembly comprises any one or any combination of red, green and blue light emitting diodes.

In one embodiment, the power conversion circuit comprises a voltage stabilizing chip, a first capacitor, a second capacitor, a first resistor and a second resistor;

the input end of the voltage stabilizing chip and the first end of the first capacitor are connected to the power supply voltage input end of the power supply conversion circuit together, the first end of the first resistor is connected to the enabling signal input end of the power supply conversion circuit, the second end of the first resistor is connected with the enabling end of the voltage stabilizing chip and the first end of the second resistor, the output end of the voltage stabilizing chip and the first end of the second capacitor are connected to the voltage stabilizing direct current output end of the power supply conversion circuit together, and the grounding end of the voltage stabilizing chip, the second end of the second resistor, the second end of the first capacitor and the second end of the second capacitor are connected to the power ground together.

In one embodiment, the control circuit comprises a microprocessor;

the first general data input and output end of the microprocessor is connected to the enabling signal output end of the control circuit, and the second general data input and output end of the microprocessor, the third general data input and output end of the microprocessor and the fourth general data input and output end of the microprocessor are connected to the control signal output end of the control circuit together.

On the other hand, the embodiment of the application also provides an electronic device, which comprises the LED brightness adjusting circuit.

In one embodiment, the electronic device is a bluetooth headset.

One of the above technical solutions has the following advantages and beneficial effects:

in each embodiment of the LED brightness adjusting circuit, the control circuit is connected to the power conversion circuit and the LED control circuit, the LED control circuit is connected to the LED module and the power ground, and the power conversion circuit can convert the power supply voltage transmitted by the power supply to obtain a stabilized dc current after voltage stabilization and transmit the stabilized dc current to the LED module; the control circuit can control the power conversion circuit to be turned on and drive the LED control circuit to be conducted to work, so that the cathode of the LED component is conducted with the power ground, and the LED component can be uniformly and consistently lightened according to the stabilized voltage direct current. This application opens or closes control to power supply switching circuit through control circuit to and through opening or close control to LED control circuit, when making the work circuit of LED subassembly switch on, power supply switching circuit carries out voltage conversion to the power supply voltage of power supply transmission and handles, and provides steady voltage direct current to the LED subassembly, makes the uniformity that the LED subassembly kept luminance, has improved the stability and the degree of consistency of LED subassembly luminance.

Drawings

FIG. 1 is a first block diagram of an LED brightness adjustment circuit according to an embodiment;

FIG. 2 is a second block diagram of an LED brightness adjustment circuit in accordance with one embodiment;

FIG. 3 is a circuit diagram of an LED brightness adjustment circuit according to an embodiment.

Detailed Description

To facilitate an understanding of the present application, the present application will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present application are shown in the drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element and be integral therewith, or intervening elements may also be present. The terms "mounted," "one end," "the other end," and the like are used herein for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In one embodiment, as shown in fig. 1, there is provided an LED brightness adjusting circuit, including:

a control circuit 110 connected to the power conversion circuit 120 and the LED control circuit 140, and configured to output an enable signal and a control signal;

a power conversion circuit 120 configured to convert a supply voltage into a regulated direct current according to an enable signal when the supply voltage is switched in;

an LED assembly 130 configured to light up according to a regulated direct current;

and an LED control circuit 140 connected to the LED assembly 130 and the power ground and configured to communicate the regulated DC power to the power ground in accordance with a control signal to control the illumination of the LED assembly.

The control circuit 110 may include a processing chip, which refers to a chip having functions of signal processing and signal transmission. The control circuit 110 may be used to control the power conversion circuit to be turned on and off; the control circuit 110 can also be used to drive the LED control circuit 140 to turn on or off, and the LED control circuit 140 can control the LED assembly 130 to turn on or off according to the control signal of the control circuit 110.

The power conversion circuit 120 refers to a conversion circuit that can convert an input power and stabilize an output power. The power conversion circuit 120 may be a voltage conversion circuit; in one example, the power conversion circuit 120 is a voltage regulator circuit. Regulated dc refers to a voltage-stabilized output dc signal. For example, the power conversion circuit 120 may perform voltage reduction processing on the power supply voltage transmitted by the power supply, and perform voltage stabilization processing on the voltage signal after voltage reduction for output, so as to obtain a stabilized dc power. The power supply may be a dc power supply; in one example, the power supply may be a battery, for example, the power supply may be a lithium battery.

The LED assembly 130 refers to a light emitting diode assembly. The LED assembly 130 may include at least one light emitting diode; in one example, the LED assembly 130 includes three light emitting diodes connected in parallel. The LED control circuit 140 may be used to control the turning on or off of the LED assembly 130.

Specifically, a power supply is connected to the power conversion circuit 120, the power conversion circuit 120 is connected to the LED assembly 130, and then the power conversion circuit 120 can convert the connected power supply voltage to obtain a regulated direct current and transmit the regulated direct current to the LED assembly 130; the power conversion circuit 120 is connected through the control circuit 110; the LED control circuit 140 is respectively connected to the LED assembly 130 and the power ground, the LED control circuit 140 is connected to the control circuit 110, and when the system is powered on, the control circuit 110 can control the power conversion circuit 120 to be turned on and drive the LED control circuit 140 to be turned on, so that the input terminal of the LED control circuit 140 is turned on to the output terminal of the LED control circuit 140, and the LED assembly 130 is turned on to the power ground, so that the LED assembly 130 can be uniformly and consistently lighted according to the voltage stabilization signal.

In the above embodiment, in the present application, the control circuit 110 controls the power conversion circuit 120 to be turned on or turned off, and the LED control circuit 140 is controlled to be turned on or turned off, so that when the working circuit of the LED component 130 is turned on, the power conversion circuit 120 performs power conversion processing on the power voltage transmitted by the power supply 140, and provides a voltage stabilizing signal to the LED component 130, so that the LED component 130 maintains the brightness consistency, and the stability and uniformity of the brightness of the LED component 130 are improved.

It should be noted that the LED brightness adjusting circuit of the present application can be applied to electronic devices. For example, the LED brightness adjustment circuit may be applied to a bluetooth headset.

In one embodiment, as in fig. 2, the LED brightness adjustment circuit further includes a first current limiting circuit 150; the first current limiting circuit 150 is connected to the power conversion circuit 120 and the LED assembly 130, and is configured to limit the regulated dc current.

The first current limiting circuit 150 can be used to limit the total input current of the LED assembly 130, so as to prevent the LED assembly 130 from being damaged or burnt out due to excessive or unstable current.

Specifically, the first current limiting circuit 150 is connected in series between the output terminal of the power conversion circuit 120 and the LED assembly 130, so that the current flowing through the LED assembly 130 can be reduced, the LED assembly 130 is prevented from being damaged, and the reliability of light emission of the LED assembly 130 is improved.

In one example, the first current limiting circuit 150 may be a first current limiting resistor.

In one embodiment, as in fig. 2, the LED brightness adjustment circuit further includes a second current limiting circuit 160;

and a second current limiting circuit 160, connected to the LED control circuit 140 and the LED assembly 130, configured to limit the regulated dc current.

The second current limiting circuit 160 can be used to limit the magnitude of the branch current of the LED device 130, so as to prevent the LED device 130 from being damaged or burned due to excessive or unstable current.

Specifically, one end of the second current limiting circuit 160 is connected to the cathode of the LED assembly 130, and the other end of the second current limiting circuit 160 is connected to the input end of the LED control circuit 140, so that the current flowing through the LED assembly 130 can be reduced, the LED assembly 130 is prevented from being damaged, and the reliability of light emission of the LED assembly 130 is improved.

Further, the LED assembly 130 may include three light emitting diodes connected in parallel, and the corresponding second current limiting circuit 160 includes three current limiting sub-circuits, the three current limiting sub-circuits are respectively connected to cathodes of the three light emitting diodes in a one-to-one correspondence, and then the three current limiting sub-circuits may respectively reduce currents flowing through the corresponding light emitting diodes, thereby playing a role in limiting current of the three light emitting diodes included in the LED assembly 130, preventing damage to the corresponding light emitting diodes, and improving reliability of light emission of the LED assembly 130.

In one example, the current limiting sub-circuit may include a second current limiting resistor.

In one embodiment, as in fig. 2, LED control circuit 140 includes a plurality of field effect transistors 142;

the drains of the fets 142 are connected to the regulated dc input of the LED control circuit 140, the sources of the fets 142 are connected to the regulated dc output of the LED control circuit 140, and the gates of the fets 142 are connected to the control signal input of the LED control circuit 140.

The fet 142 may be a PNP fet or an NPN fet.

Specifically, based on that the drains of the fets 142 are connected to the regulated dc input terminal of the LED control circuit 140, the sources of the fets 142 are connected to the regulated dc output terminal of the LED control circuit 140, and the gates of the fets 142 are connected to the control signal input terminal of the LED control circuit 140, the control circuit 110 can transmit a driving signal to the gates of the fets 142 to turn on the fets 142, i.e., to turn on the channels between the sources and the drains of the fets 142, so that the corresponding LEDs in the LED assembly 130 are connected to the ground, thereby turning on the working circuits of the corresponding LEDs, and enabling the LED assembly 130 to emit light with uniform brightness based on the regulated dc.

In one embodiment, as in fig. 2, the LED brightness adjustment circuit further comprises a plurality of pull-down resistors 180;

first ends of the pull-down resistors 170 are respectively connected to gates of the field effect transistors, and second ends of the pull-down resistors are commonly connected to a power ground.

Wherein the pull-down resistors 170 are directly connected to the power ground.

Specifically, one end of the pull-down resistors 170 is connected to the gates of the fets 142, and the other end of the pull-down resistors 170 is connected to the ground, so that when the control circuit 110 does not transmit a driving signal to the gates of the fets 142, the gates of the fets 142 are kept in a low level state based on the function of the pull-down resistors 170, and the fets 142 are kept in an off state. When the control circuit 110 transmits a driving signal to the gate of the fet 142, the gate of the fet 142 is in a high state, and the fet 142 is in a conducting state. By providing the pull-down resistor 170 at the gate of the fet 142, the reliability of the turn-on and turn-off of the fet 142 is improved.

In one embodiment, as shown in fig. 3, the power conversion circuit includes a voltage regulation chip U1, a first capacitor C1, a second capacitor C2, a first resistor R1, and a second resistor R2;

an input end IN of the voltage stabilizing chip U1 and a first end of the first capacitor C1 are commonly connected to a Power supply voltage input end SYS _ Power of the Power supply conversion circuit, a first end of the first resistor R1 is connected to an enable signal input end LED _ EN of the Power supply conversion circuit, a second end of the first resistor R1 is connected with an enable end EN of the voltage stabilizing chip U1 and a first end of the second resistor R2, an output end OUT of the voltage stabilizing chip U1 and a first end of the second capacitor C2 are commonly connected to an output end of the stabilized direct current of the Power supply conversion circuit, and a ground end GND of the voltage stabilizing chip U1, a second end of the second resistor R2, a second end of the first capacitor C1 and a second end of the second capacitor C2 are commonly connected to a Power ground.

Based on the first end of the first capacitor C1 being connected to the supply voltage input end SYS _ Power of the Power conversion circuit 120, the second end of the first capacitor C1 being connected to the Power ground, the first capacitor C1 can filter out a peak voltage carried by the supply voltage input at the input end of the Power conversion circuit 120, so that the regulated dc Power converted and processed by the Power conversion circuit 120 is more stable and reliable. Based on the fact that the first end of the second capacitor C2 is connected to the output end of the regulated dc power of the power conversion circuit 120, the second end of the second capacitor C2 is connected to the power ground, and further the second capacitor C2 can filter the peak voltage carried by the regulated dc power output by the output end of the power conversion circuit 120, so that the regulated dc power converted by the power conversion circuit 120 is more stable and reliable.

In one embodiment, as in fig. 3, the control circuit includes a microprocessor U2;

the first universal data input and output end P1.0 of the microprocessor U2 is connected to the enable signal output end of the control circuit, and the second universal data input and output end P1.1 of the microprocessor U2, the third universal data input and output end P1.2 of the microprocessor U2 and the fourth universal data input and output end P1.3 of the microprocessor U2 are commonly connected to the control signal output end of the control circuit.

In one embodiment, the LED assembly includes any one or any combination of red, green and blue light emitting diodes.

Specifically, as in fig. 3, the LED assembly D4 may include a red light emitting diode R, a green light emitting diode G, and a blue light emitting diode B. The first current limiting circuit is a third current limiting resistor R3, and the second current limiting circuit comprises a fourth current limiting resistor R4, a fifth current limiting resistor R5 and a sixth current limiting resistor R6. The LED control circuit includes a first fet Q1, a second fet Q2, and a third fet Q3. The pull-down resistors include a first pull-down resistor R7, a second pull-down resistor R8 and a third pull-down resistor R9.

Further, the red light emitting diode R, the green light emitting diode G and the blue light emitting diode B are connected in parallel with each other. Anodes of the red light emitting diode R, the green light emitting diode G and the blue light emitting diode B are respectively connected with an output end OUT of the voltage stabilizing chip U1. The cathode of the red light emitting diode R is connected with the first end of a sixth current limiting resistor R6, the second end of the sixth current limiting resistor R6 is connected with the source electrode of a third field effect transistor Q3, the drain electrode of the third field effect transistor Q3 is connected with the power ground, and the grid electrode of the third field effect transistor Q3 is connected with a fourth universal data input and output end P1.3 of the microprocessor; a first terminal of the third pull-down resistor R9 is connected to the gate of the third fet Q3, and a second terminal of the third pull-down resistor R9 is connected to ground. The cathode of the green light emitting diode G is connected with the first end of a fifth current-limiting resistor R5, the second end of the fifth current-limiting resistor R5 is connected with the source electrode of a second field effect transistor Q2, the drain electrode of the second field effect transistor Q2 is connected with the power ground, and the grid electrode of the second field effect transistor Q2 is connected with a third general data input/output end P1.2 of the microprocessor; a first terminal of the second pull-down resistor R8 is connected to the gate of the second fet Q2, and a second terminal of the second pull-down resistor R8 is connected to ground. The cathode of the blue light emitting diode B is connected with one end of a fourth current limiting resistor R4, the second end of the fourth current limiting resistor R4 is connected with the source electrode of a second field effect transistor Q1, the drain electrode of the first field effect transistor Q1 is connected with the power ground, and the gate electrode of the first field effect transistor Q1 is connected with a second general data input and output end P1.1 of the microprocessor U2; the first end of the first pull-down resistor R7 is connected to the gate of the first FET Q1, and the second end of the first pull-down resistor R7 is connected to ground.

Further, the regulator chip U1 may be a SGM2036 type regulator chip. The input end IN of the voltage stabilization chip U1 is connected with a power supply, the enable end EN of the voltage stabilization chip U1 is connected with a first general data input and output end P1.0 pin of the processor U2, the output end OUT of the voltage stabilization chip U1 is connected with a third current limiting resistor R3, and the ground end GND of the voltage stabilization chip U1 is connected with the power ground.

In one example, a first terminal of the second capacitor C2 is connected to the output terminal OUT of the regulator chip U1, and a second terminal of the second capacitor C2 is connected to the power ground.

IN one example, a first terminal of the first capacitor C1 is connected to the input terminal IN of the regulator chip U1, and a second terminal of the first capacitor C1 is connected to the power ground.

In one example, the voltage of the regulated direct current output by the OUT pin of the regulator chip U1 is 3.3 volts.

Specifically, when the system is powered on, the voltage of 3.3V can be stably output through the voltage stabilizing chip U1 to supply power to the LED assembly D4 (red light emitting diode R, green light emitting diode G, and blue light emitting diode B), so as to ensure the brightness consistency of the LED assembly.

In the above embodiment, the power supply circuit controls the power conversion circuit to be turned on or turned off, and the LED control circuit is controlled to be turned on or turned off, so that when the working circuit of the LED module is switched on, the power conversion circuit performs power conversion processing on the power voltage transmitted by the power supply and provides a voltage stabilization signal to the LED module, so that the LED module maintains the brightness consistency, and the stability and the uniformity of the brightness of the LED module are improved.

In one example, an electronic device is also provided, which includes the LED brightness adjusting circuit of any one of the above.

Specifically, the electronic device is a bluetooth headset.

Furthermore, the power supply conversion circuit is connected with the power supply voltage of the power supply, the output end of the power supply conversion circuit is connected with the anode of the LED assembly, and the power supply conversion circuit can convert the power supply voltage transmitted by the power supply to obtain stabilized direct current after voltage stabilization and transmit the stabilized direct current to the LED assembly; the control circuit is connected with the control end of the power supply conversion circuit; the input end of the LED control circuit is connected with the cathode of the LED component, the output end of the LED control circuit is connected with a power ground, the control end of the LED control circuit is connected with the control circuit, the control circuit controls the power conversion circuit to be turned on and drives the LED control circuit to be conducted, so that the input end and the output end of the LED control circuit are conducted, the cathode and the ground of the LED component are conducted, and the LED component can be uniformly and consistently lightened according to the voltage-stabilized direct current.

In the above embodiment, the control circuit controls the power conversion circuit to be turned on or turned off, and the control circuit controls the LED control circuit to be turned on or turned off, so that when the working circuit of the LED module is switched on, the power conversion circuit performs power conversion processing on the power voltage transmitted by the power supply, and provides a regulated direct current to the LED module, so that the LED module maintains the brightness consistency, and the stability and the uniformity of the brightness of the LED module are improved.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. An LED brightness adjusting circuit, characterized by further comprising:

the power supply conversion circuit is configured to convert a power supply voltage into a stabilized direct current according to the enable signal when the power supply voltage is switched in;

an LED component configured to be lit according to the regulated direct current;

the LED control circuit is connected with the LED assembly and a power ground and is configured to communicate the regulated direct current to the power ground according to the control signal so as to control the lighting of the LED assembly.

2. The LED brightness adjustment circuit of claim 1, further comprising:

3. The LED brightness adjustment circuit of claim 1, further comprising:

and the second current limiting circuit is connected with the LED control circuit and the LED assembly and is configured to limit the regulated direct current.

4. The LED brightness adjustment circuit of claim 1, wherein the LED control circuit comprises a plurality of fets;

5. The LED brightness adjustment circuit of claim 4, further comprising a plurality of pull-down resistors;

the first ends of the pull-down resistors are respectively connected with the grids of the field effect transistors, and the second ends of the pull-down resistors are connected to a power ground in common.

6. The LED brightness adjustment circuit of claim 1, wherein the LED component comprises any one or any combination of a red LED, a green LED and a blue LED.

7. The LED brightness adjusting circuit of claim 1, wherein the power conversion circuit comprises a voltage stabilizing chip, a first capacitor, a second capacitor, a first resistor and a second resistor;

the input end of the voltage stabilizing chip and the first end of the first capacitor are connected to the power supply voltage input end of the power supply conversion circuit together, the first end of the first resistor is connected to the enabling signal input end of the power supply conversion circuit, the second end of the first resistor is connected with the enabling end of the voltage stabilizing chip and the first end of the second resistor, the output end of the voltage stabilizing chip and the first end of the second capacitor are connected to the output end of the stabilized voltage direct current of the power supply conversion circuit together, and the grounding end of the voltage stabilizing chip, the second end of the second resistor, the second end of the first capacitor and the second end of the second capacitor are connected to a power ground in common.

8. The LED brightness adjustment circuit of claim 1, wherein the control circuit comprises a microprocessor;

the first general data input and output end of the microprocessor is connected to the enable signal output end of the control circuit, and the second general data input and output end of the microprocessor, the third general data input and output end of the microprocessor and the fourth general data input and output end of the microprocessor are connected to the control signal output end of the control circuit together.

9. An electronic device, comprising the LED brightness adjusting circuit of any one of claims 1 to 8.

10. The electronic device of claim 9, wherein the electronic device is a bluetooth headset.