Vehicle-mounted radio power supply circuit and vehicle-mounted radio

Abstract

The utility model provides a vehicle-mounted radio power supply circuit and a vehicle-mounted radio, the circuit comprises a power supply control circuit, a voltage transformation circuit and an output switch circuit, the voltage transformation circuit comprises a transformer, a first switch tube, a second switch tube, a first resistor, a second resistor, a third resistor and a first capacitor, the output switch circuit comprises a fourth resistor, a fifth resistor, a second capacitor and a third switch tube, under the condition that the vehicle-mounted radio power supply circuit is powered on, the third switch tube is switched on when the control end of the third switch tube is at a high level, and the second capacitor is used for stabilizing output voltage, avoiding voltage mutation, filtering interference signals and ensuring power supply output; the second ends of the first switch tube and the second switch tube and one end of the transformer are grounded, so that current can directly flow into the ground when equipment fails or personnel operates mistakenly, damage to personnel and equipment is avoided, the third switch tube is turned off when the control end of the third switch tube is at a low level, and faults caused by long-term over-low voltage power supply are prevented.

Description

Technical Field

[0001] The present disclosure relates to the technical field of vehicle-mounted radios, and in particular to a vehicle-mounted radio power supply circuit and a vehicle-mounted radio. Background Art

[0002] Car radios are currently used in a wide range of vehicles as audio entertainment devices. They typically connect to AC power, rectify it, and then step it down, ultimately outputting DC power to power the radio. However, if the stepped-down DC power fluctuates or is too low, it can't stably power the radio, hindering user experience and preventing them from receiving the audio. Utility Model Content

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a vehicle-mounted radio power supply circuit and a vehicle-mounted radio that can provide stable power supply and can disconnect the power supply when the voltage is low.

[0004] The purpose of this disclosure is achieved through the following technical solutions:

[0005] A vehicle-mounted radio power supply circuit, comprising:

[0006] A power supply control circuit, wherein the input terminal of the power supply control circuit is used to receive alternating current;

[0007] A voltage conversion circuit includes a transformer, a first switching transistor, a second switching transistor, a first resistor, a second resistor, a third resistor, and a first capacitor. The first end of the first resistor is respectively connected to the output end of the power control circuit and the input end of the transformer. The second end of the first resistor is respectively connected to the lower half end of the first capacitor, the control end of the first switching transistor, and the first end of the second switching transistor. The upper half end of the first capacitor is connected to the output end of the transformer, and both output ends of the transformer are grounded. The first end of the first switching transistor is connected to both input ends of the transformer. The second end of the first switching transistor is respectively connected to the first end of the second resistor and the first end of the third resistor. The second end of the second resistor is connected to the control end of the second switching transistor. The second end of the second switching transistor is grounded. The second end of the third resistor is connected to the second end of the second switching transistor.

[0008] The output switching circuit includes a fourth resistor, a fifth resistor, a second capacitor, and a third switching tube. The first end of the fourth resistor is connected to one input terminal of the transformer, the second end of the fourth resistor is respectively connected to two input terminals of the transformer, the first end of the fifth resistor, and the first end of the third switching tube. The second end of the fifth resistor is respectively connected to the control terminal of the third switching tube and the upper half end of the second capacitor. The second end of the third switching tube is used to connect to the positive end of the output lead, and the lower half end of the second capacitor is used to connect to the negative end of the output lead.

[0009] In one embodiment, the voltage conversion circuit further includes a first general diode, a positive end of the first general diode is connected to the second end of the second switch tube, and a negative end of the first general diode is connected to the first end of the second switch tube.

[0010] In one embodiment, the voltage conversion circuit further includes a sixth resistor, a first end of the sixth resistor is connected to an output end of the transformer, and a second end of the sixth resistor is connected to an upper half end of the first capacitor.

[0011] In one embodiment, the voltage conversion circuit further includes a seventh resistor, an upper end of the seventh resistor is connected to the first end of the third resistor, and a lower end of the seventh resistor is connected to the second end of the third resistor.

[0012] In one embodiment, the output switch circuit further includes a third capacitor, an upper half of the third capacitor is connected to an upper half of the fourth resistor, and a lower half of the third capacitor is connected to the first end of the fifth resistor.

[0013] In one embodiment, the output switch circuit further includes a voltage regulator diode, a positive terminal of the voltage regulator diode is connected to the lower half of the third capacitor, and a negative terminal of the voltage regulator diode is connected to the second end of the fifth resistor.

[0014] In one embodiment, the output switch circuit further includes a second general diode, a positive terminal of the second general diode is connected to the first terminal of the first switch tube, and a negative terminal of the second general diode is connected to the positive terminal of the Zener diode.

[0015] In one embodiment, the output switch circuit further includes a third general diode, a positive end of the third general diode is connected to the first end of the fourth resistor, and a negative end of the third general diode is connected to the first end of the third switch tube.

[0016] In one embodiment, the fourth resistor is a load resistor.

[0017] A car radio comprises the car radio power supply circuit described in any one of the above embodiments.

[0018] Compared with the prior art, the present disclosure has at least the following advantages:

[0019] The aforementioned car radio power supply circuit, when connected to power, outputs AC power through rectification and transformation. The third switch controls the on / off state of the car radio, turning it on when its control terminal is at a high level. The second capacitor stabilizes the output voltage to prevent sudden voltage changes and filters interference signals to ensure power output. The first and second switches are configured to ground the current, and one end of the transformer is grounded. This ensures that in the event of equipment failure or human error, the current flows directly to the ground, thereby preventing damage to personnel and equipment. The third switch shuts down when its control terminal is at a low level, i.e., when the voltage is low. This circuit provides stable power supply and can disconnect the power supply when the voltage is low, preventing device failure caused by long-term low-voltage power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 FIG. 4 is a circuit diagram of a vehicle-mounted radio power supply circuit in one embodiment.

[0022] Figure numerals: 10, vehicle-mounted radio power supply circuit; 100, power supply control circuit; 200, voltage conversion circuit; 300, output switching circuit; T1, transformer; Q1, first switching tube; Q2, second switching tube; Q3, third switching tube; R1, first resistor; R4, second resistor; R5, third resistor; RL, fourth resistor; R11, fifth resistor; R3, sixth resistor; R6, seventh resistor; C3, first capacitor; C6, second capacitor; C4, third capacitor; Z1, voltage regulator diode; D1, first general-purpose diode; D2, second general-purpose diode; D3, third general-purpose diode. DETAILED DESCRIPTION

[0023] To facilitate understanding of the present disclosure, a more comprehensive description of the present disclosure will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present disclosure. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure.

[0024] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. The terms used herein in the specification of this disclosure are intended only to describe specific embodiments and are not intended to limit this disclosure. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] In order to better understand the technical solutions and beneficial effects of the present disclosure, the present disclosure is further described in detail below with reference to specific embodiments:

[0027] See also Figure 1 , which is an embodiment of the present invention, a vehicle-mounted radio power supply circuit 10 includes a power control circuit 100 , a voltage conversion circuit 200 and an output switch circuit 300 .

[0028] The input terminal of the power control circuit 100 is used to connect to AC power; the voltage conversion circuit 200 includes a transformer T1, a first switching transistor Q1, a second switching transistor Q2, a first resistor R1, a second resistor R4, a third resistor R5, and a first capacitor C3. The first end of the first resistor R1 is respectively connected to the output terminal of the power control circuit 100 and the input terminal of the transformer T1. The second end of the first resistor R1 is respectively connected to the lower half end of the first capacitor C3, the control terminal of the first switching transistor Q1, and the first end of the second switching transistor Q2. The upper half end of the first capacitor C3 is connected to the output terminal of the transformer T1, and the output terminals of the transformer T1 are grounded. The first end of the first switching transistor Q1 is connected to the input terminals of the transformer T1, and the second end of the first switching transistor Q1 is respectively connected to the first end of the second resistor R4 and the third resistor R5. 5, a second end of the second resistor R4 is connected to the control end of the second switch transistor Q2, the second end of the second switch transistor Q2 is grounded, and a second end of the third resistor R5 is connected to the second end of the second switch transistor Q2; the output switch circuit 300 includes a fourth resistor RL, a fifth resistor R11, a second capacitor C6 and a third switch transistor Q3. The first end of the fourth resistor RL is connected to one input end of the transformer T1, the second end of the fourth resistor RL is respectively connected to two input ends of the transformer T1, the first end of the fifth resistor R11 and the first end of the third switch transistor Q3, the second end of the fifth resistor R11 is respectively connected to the control end of the third switch transistor Q3 and the upper half end of the second capacitor C6, the second end of the third switch transistor Q3 is used to connect to the positive terminal of the output lead, and the lower half end of the second capacitor C6 is used to connect to the negative terminal of the output lead.

[0029] In this embodiment, when the car radio power supply circuit 10 is connected to power, AC power is rectified and transformed before being output. The third switch Q3 controls the on / off state of the car radio and is turned on when its control terminal is at a high level. The second capacitor C6 stabilizes the output voltage, preventing sudden voltage changes and filtering interference signals to ensure power output. The first and second switches Q1 and Q2 are configured to ground the current, and one end of the transformer T1 is grounded. This ensures that in the event of equipment failure or human error, the current flows directly to the ground, thus preventing damage to personnel and equipment. The third switch Q3 is turned off when its control terminal is at a low level, i.e., when the voltage is low. This circuit provides stable power supply and can disconnect the power supply when the voltage is low, preventing device failure caused by long-term undervoltage power supply. The output end of the transformer T1 is connected to the first capacitor C3, effectively improving power supply efficiency. Grounding the same end of the transformer T1 enhances device safety.

[0030] Furthermore, the first switching transistor Q1 and the second switching transistor Q2 are both NPN transistors for amplifying output current. Their first terminals are collectors, their second terminals are emitters, and their control terminals are bases. The third switching transistor Q3 is an N-type MOS transistor for amplifying output voltage to provide sufficient voltage for powering a car radio. Its first terminal is a drain, its second terminal is a source, and its control terminal is a gate.

[0031] In one embodiment, the voltage conversion circuit 200 further includes a first general-purpose diode D1, wherein the positive terminal of the first general-purpose diode D1 is connected to the second terminal of the second switching transistor Q2, and the negative terminal of the first general-purpose diode D1 is connected to the first terminal of the second switching transistor Q2. In this embodiment, the positive terminal of the first general-purpose diode D1 is connected to the emitter of the NPN transistor, and the negative terminal of the first general-purpose diode D1 is connected to the collector of the NPN transistor. It is understood that when the second switching transistor Q2 is operating, the voltage between the first and second terminals, i.e., between the collector and emitter, may be very high, which can easily lead to overvoltage damage. The first general-purpose diode D1 can thus act as a voltage stabilizer, thereby reducing the voltage between the first and second terminals of the second switching transistor Q2, thereby increasing the operating current of the transistor.

[0032] In one embodiment, the voltage conversion circuit 200 further includes a sixth resistor R3, wherein a first terminal of the sixth resistor R3 is connected to an output terminal of the transformer T1, and a second terminal of the sixth resistor R3 is connected to the upper half of the first capacitor C3. It will be appreciated that the configuration of the sixth resistor R3 can limit the current at the output terminal of the transformer T1. Furthermore, the series connection of the sixth resistor R3 and the first capacitor C3 can absorb peak voltages during switching, protecting circuit components from damage caused by these peak voltages.

[0033] In one embodiment, the voltage conversion circuit 200 further includes a seventh resistor R6. The upper end of the seventh resistor R6 is connected to the first end of the third resistor R5, and the lower end of the seventh resistor R6 is connected to the second end of the third resistor R5. It will be appreciated that the third resistor R5 and the seventh resistor R6 are connected in parallel to achieve a current shunting effect, further limiting the current output from the second end of the first switch Q1, thereby protecting the first switch Q1 from excessive current between its first and second ends, which could cause a breakdown.

[0034] In one embodiment, the output switching circuit 300 further includes a third capacitor C4. The upper half of the third capacitor C4 is connected to the upper half of the fourth resistor RL, and the lower half of the third capacitor C4 is connected to the first end of the fifth resistor R11. It will be appreciated that the third capacitor C4 and the fourth resistor RL are connected in parallel to form a capacitor-resistor circuit, which is used to filter interference signals from the output current and ensure that the output DC power can stably power the car radio. In this embodiment, the capacitance of the third capacitor C4 is 330 μF, which is in the nanofarad range and is used to filter low-frequency signals.

[0035] In one embodiment, the output switch circuit 300 further includes a Zener diode Z1. The positive terminal of the Zener diode Z1 is connected to the lower half of the third capacitor C4, and the negative terminal of the Zener diode Z1 is connected to the second end of the fifth resistor R11. It will be appreciated that the Zener diode Z1 is connected in parallel with the fifth resistor R11. When the Zener diode Z1 is conducting, the current flowing through the Zener diode Z1 is limited by the fifth resistor R11, preventing damage to the car radio caused by excessive current.

[0036] In one embodiment, the output switch circuit 300 further includes a second general-purpose diode D2. The positive terminal of the second general-purpose diode D2 is connected to the first terminal of the first switch transistor Q1, and the negative terminal of the second general-purpose diode D2 is connected to the positive terminal of the Zener diode Z1. It will be appreciated that the provision of the second general-purpose diode D2 ensures unidirectional current flow and prevents current backflow that could damage circuit components.

[0037] In one embodiment, the output switch circuit 300 further includes a third general-purpose diode D3. The positive terminal of the third general-purpose diode D3 is connected to the first terminal of the fourth resistor RL, and the negative terminal of the third general-purpose diode D3 is connected to the first terminal of the third switch Q3. It is understood that the third general-purpose diode D3 and the fourth resistor RL are connected in parallel. The third general-purpose diode D3 is used to shape the signal into a unidirectional signal, and the fourth resistor RL is used to limit current to prevent overcurrent from damaging the third general-purpose diode D3.

[0038] In one embodiment, the fourth resistor RL is a load resistor. It will be understood that a load resistor is a resistor device that absorbs a portion of the output signal power, thereby making the entire circuit more stable and reliable. Specifically, the load resistor absorbs power from the power supply and the transformed signal output, converting it into heat energy and dissipating it, thereby ensuring the normal operation of the circuit and, by extension, the car radio.

[0039] The present disclosure further provides a car radio, comprising the car radio power supply circuit 10 according to any one of the above embodiments.

[0040] Compared with the prior art, the present disclosure has at least the following advantages:

[0041] The aforementioned car radio power supply circuit 10, when connected to power, outputs AC power after rectification and transformation. The third switch Q3 controls the on / off state of the car radio, turning on when its control terminal is at a high level. The second capacitor C6 stabilizes the output voltage, preventing sudden voltage changes and filtering interference signals to ensure power output. The first and second switches Q1 and Q2 are configured to ground the current, and one end of the transformer T1 is grounded. This ensures that in the event of equipment failure or human error, the current flows directly to the ground, thereby preventing damage to personnel and equipment. The third switch Q3 is turned off when its control terminal is at a low level, i.e., when the voltage is low. This circuit provides stable power supply and can disconnect the power supply when the voltage is low, preventing device failure caused by long-term low-voltage power supply.

[0042] The above-described embodiments merely represent several implementation methods of the present disclosure. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the disclosed patent. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the scope of the present disclosure, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the disclosed patent shall be determined by the appended claims.

Claims

1. A car radio power supply circuit, characterized in that: include: A power supply control circuit, wherein the input terminal of the power supply control circuit is used to receive alternating current; A voltage conversion circuit includes a transformer, a first switching transistor, a second switching transistor, a first resistor, a second resistor, a third resistor, and a first capacitor. The first end of the first resistor is respectively connected to the output end of the power control circuit and the input end of the transformer. The second end of the first resistor is respectively connected to the lower half end of the first capacitor, the control end of the first switching transistor, and the first end of the second switching transistor. The upper half end of the first capacitor is connected to the output end of the transformer, and both output ends of the transformer are grounded. The first end of the first switching transistor is connected to both input ends of the transformer. The second end of the first switching transistor is respectively connected to the first end of the second resistor and the first end of the third resistor. The second end of the second resistor is connected to the control end of the second switching transistor. The second end of the second switching transistor is grounded. The second end of the third resistor is connected to the second end of the second switching transistor. The output switching circuit includes a fourth resistor, a fifth resistor, a second capacitor, and a third switching tube. The first end of the fourth resistor is connected to one input terminal of the transformer, the second end of the fourth resistor is respectively connected to two input terminals of the transformer, the first end of the fifth resistor, and the first end of the third switching tube. The second end of the fifth resistor is respectively connected to the control terminal of the third switching tube and the upper half end of the second capacitor. The second end of the third switching tube is used to connect to the positive end of the output lead, and the lower half end of the second capacitor is used to connect to the negative end of the output lead.

2. The vehicle-mounted radio power supply circuit according to claim 1, characterized in that: The voltage conversion circuit further includes a first general diode, a positive end of the first general diode is connected to the second end of the second switch tube, and a negative end of the first general diode is connected to the first end of the second switch tube.

3. The vehicle-mounted radio power supply circuit according to claim 1, characterized in that: The voltage conversion circuit further includes a sixth resistor, a first end of the sixth resistor is connected to an output end of the transformer, and a second end of the sixth resistor is connected to an upper half end of the first capacitor.

4. The vehicle-mounted radio power supply circuit according to claim 1, characterized in that: The voltage conversion circuit further includes a seventh resistor, wherein an upper end of the seventh resistor is connected to the first end of the third resistor, and a lower end of the seventh resistor is connected to the second end of the third resistor.

5. The vehicle-mounted radio power supply circuit according to claim 1, characterized in that: The output switch circuit further includes a third capacitor, an upper half end of the third capacitor is connected to an upper half end of the fourth resistor, and a lower half end of the third capacitor is connected to a first end of the fifth resistor.

6. The vehicle-mounted radio power supply circuit according to claim 5, characterized in that: The output switch circuit further includes a voltage regulator diode, a positive end of the voltage regulator diode is connected to the lower half end of the third capacitor, and a negative end of the voltage regulator diode is connected to the second end of the fifth resistor.

7. The vehicle-mounted radio power supply circuit according to claim 6, characterized in that: The output switch circuit further includes a second general diode, a positive end of the second general diode is connected to the first end of the first switch tube, and a negative end of the second general diode is connected to the positive end of the voltage regulator diode.

8. The vehicle-mounted radio power supply circuit according to claim 1, characterized in that: The output switch circuit further includes a third general diode, a positive end of the third general diode is connected to the first end of the fourth resistor, and a negative end of the third general diode is connected to the first end of the third switch tube.

9. The vehicle-mounted radio power supply circuit according to claim 1, characterized in that: The fourth resistor is a load resistor.

10. A car radio, characterized in that: The vehicle-mounted radio power supply circuit comprises the vehicle-mounted radio power supply circuit according to any one of claims 1 to 9.

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