CN210201711U - Circuit for reducing sleep current of vehicle-mounted multimedia system - Google Patents
Circuit for reducing sleep current of vehicle-mounted multimedia system Download PDFInfo
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- CN210201711U CN210201711U CN201921054147.3U CN201921054147U CN210201711U CN 210201711 U CN210201711 U CN 210201711U CN 201921054147 U CN201921054147 U CN 201921054147U CN 210201711 U CN210201711 U CN 210201711U
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Abstract
The application relates to a circuit for reducing the sleep current of a vehicle-mounted multimedia system, which at least comprises a vehicle-mounted storage battery, a switch circuit, a power regulating circuit and a main control chip, wherein the vehicle-mounted storage battery is connected with the main control chip through the switch circuit; the voltage input end of the power regulating circuit is connected with the voltage output end of the switch circuit, the signal input end of the power regulating circuit is connected with the signal output end of the main control chip, and the power regulating circuit controls the power of the switch circuit by receiving a level signal from the main control chip. The beneficial effects are that: through being provided with power regulating circuit to the operating frequency of control switch circuit under different operating condition has effectually reduced on-vehicle multi-media system's sleep current, and guarantees that AM radio reception signal is not disturbed.
Description
Technical Field
The application relates to the technical field of automotive electronics, in particular to a circuit for reducing sleep current of a vehicle-mounted multimedia system.
Background
The switch power supply is equipment for realizing power supply conversion by controlling the continuous on and off of a switch through pulse width or frequency, and can convert a storage battery power supply into high-quality direct-current voltage meeting equipment requirements; the vehicle-mounted electronic device has the characteristics of high efficiency, small heat productivity and strong load carrying capacity, and is more and more widely used in vehicle-mounted electronic products. Due to the high-frequency switching function of the switching power supply, along with the function of the vehicle-mounted multimedia system becoming more and more powerful, the intervals of the circuit modules on the PCB board become more and more crowded, and the interference on the sensitive radio module circuit becomes more and more obvious. The main reason is that the switching frequency of the switching power supply is different from several Hz to MHz, the frequency range of the wave band in the AM of the radio in our country is 531 KHz-1602 KHz, and the frequency multiplication of the switching frequency and the switching frequency thereof is easy to interfere the reception of the AM signal, so that the AM radio reception effect is poor.
In order to reduce the interference of the switching power supply to the AM signal of the radio, many multi-chip manufacturers design the frequency of the switching power supply to be higher and higher in the current market. The design of the vehicle-mounted multimedia system also sets the frequency of the DC/DC switching power supply on the highest frequency allowed by the chip, thereby avoiding the interference to the operating frequency band 531 KHz-1602 KHz of the radio module. However, in recent years, with the attention of the whole car factory on the sleep current of the vehicle-mounted multimedia system, wherein the sleep current refers to the current consumed by the multimedia system when the multimedia system works in a sleep mode, the situation that the storage battery is consumed too fast to cause feeding in a non-starting state of the car is prevented, and the standard of the sleep current is gradually changed from 3mA to 0.4mA or even lower. In this case, the problem of the operating frequency of the switching power supply needs to be considered, and theoretically, the higher the frequency is, the larger the switching loss is, and the larger the consumed current is. At the same 0.01A current output, the operating efficiency at 2200KHz is only around 60% at a battery voltage of 12V, while 90% at 400KHz, i.e., the sleep current differs by 30% in both cases.
From the above, meeting the increasingly strict sleep current standard requirement of the whole car factory under the condition that the sound reception is not interfered is an urgent need to solve the problem based on the current design.
Disclosure of Invention
In order to solve the technical problems, the application provides a circuit for reducing the sleep current of a vehicle-mounted multimedia system, which at least comprises a vehicle-mounted storage battery, a switch circuit, a power regulating circuit and a main control chip, wherein the vehicle-mounted storage battery is connected with the main control chip through the switch circuit; the voltage input end of the power regulating circuit is connected with the voltage output end of the switch circuit, the signal input end of the power regulating circuit is connected with the signal output end of the main control chip, and the power regulating circuit controls the power of the switch circuit by receiving a level signal from the main control chip.
Preferably, the power regulating circuit includes a first resistor, a second resistor, and a transistor, the first resistor and the second resistor are both connected in parallel to the voltage output terminal of the switching circuit, the other end of the first resistor is connected to the collector of the transistor, and the other end of the second resistor is connected to ground.
Preferably, the base electrode of the triode is connected to the signal output end of the main control chip, and the emitter electrode of the triode is grounded.
Preferably, a first parasitic resistor is further connected between the base of the triode and the signal output end, and a second parasitic resistor is connected between the emitter and the base of the triode.
Preferably, the power regulating circuit includes a first resistor, a second resistor, and an NMOS transistor, where the first resistor and the second resistor are both connected in parallel to the voltage output terminal of the switching circuit, the other end of the first resistor is connected to the drain of the NMOS transistor, and the other end of the second resistor is connected to ground.
Preferably, the gate of the NMOS transistor is grounded to the signal output terminal and the source of the main control chip.
Preferably, the second resistance value is greater than the first resistance value.
Preferably, the switching circuit is a DC-DC buck type circuit.
Preferably, the switching circuit comprises a switching power supply chip, and the on-vehicle storage battery and a power input end of the switching power supply chip are sequentially connected with a diode, an inductor, at least one capacitor and at least one resistor; and the power output end of the switching power supply chip is connected with the main control chip sequentially through an inductor, at least one capacitor and at least one resistor.
Preferably, the control circuit further comprises an LDO linear power supply circuit connected between the switch circuit and the main control chip.
The utility model provides a reduce circuit of on-vehicle hypersystem sleep current, its beneficial effect lies in:
(1) the power regulating circuit is arranged to control the working frequency of the switching circuit in different working states, so that the sleep current of the vehicle-mounted multimedia system is effectively reduced, and the AM radio signal is ensured not to be interfered;
(2) the power regulating circuit comprises a resistor, a triode or an NMOS tube, has a simple structure, does not need special devices and has high cost;
(3) the service life of the vehicle-mounted storage battery is prolonged, premature feeding of the storage battery is prevented, and circuit elements of vehicle-mounted multimedia are effectively protected.
Drawings
FIG. 1 is a schematic circuit flow diagram according to an embodiment of the present application;
FIG. 2 is a circuit diagram of an embodiment of the present application;
the intelligent control system comprises a vehicle-mounted storage battery 1, a switch circuit 2, a main control chip 3, a power regulation circuit 4, a tail tooth circuit 5, a U1 switch power supply chip, a Vin power supply input end, a Vout power supply output end, a Q1 triode, a R1 first resistor, a R2 second resistor and an MCU _ GPIO signal output end.
The drawings are for illustrative purposes only and are not to be construed as limiting the patent; for the purpose of better illustrating the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted; the same or similar reference numerals correspond to the same or similar parts; the terms describing positional relationships in the drawings are for illustrative purposes only and are not to be construed as limiting the patent.
Detailed Description
The following detailed description of the preferred embodiments of the present application, taken in conjunction with the accompanying drawings, will make the advantages and features of the present application more readily appreciated by those skilled in the art, and thus will more clearly define the scope of the invention.
In the embodiment shown in fig. 1-2, the present application provides a circuit for reducing a sleep current of a vehicle-mounted multimedia system, which at least includes a vehicle-mounted storage battery 1, a switch circuit 2, a power regulating circuit 4, and a main control chip 3, wherein the vehicle-mounted storage battery 1 is connected to the main control chip 3 through the switch circuit 2; the voltage input end of the power regulating circuit 4 is connected to the voltage output end FREQ of the switch circuit 2, the signal input end of the power regulating circuit 4 is connected to the signal output end MCU _ GPIO of the main control chip 3, and the power regulating circuit 4 controls the power of the switch circuit 2 by receiving the level signal from the main control chip 3. This application is through setting up power regulating circuit 4 at switch circuit 2, and the break-make of power regulating circuit 4 is controlled by main control chip 3, in this embodiment, the power regulating circuit 4 of connection at switch circuit 2 is the changeable load of resistance, if when on-vehicle multimedia system normally works, main control chip normally works and exports the high level to power regulating circuit 4 through signal output part MCU _ GPIO, make its power regulating circuit switch on, make the load resistance of connection at switch circuit 2 reduce, switch circuit's frequency is higher than the frequency of AM radio reception signal, make it not disturb AM radio reception signal. If the vehicle-mounted multimedia system enters the sleep mode, the main control chip enters the sleep mode and outputs a low level to the power regulating circuit 4 through the signal output end MCU _ GPIO, so that the power regulating circuit is turned off, the resistance value of a load connected with the switch circuit 2 is increased, the frequency of the switch circuit 2 is lower than that of an AM radio signal, and the sleep current of the vehicle-mounted multimedia system is reduced. The power regulating circuit is arranged to control the working frequency of the switching circuit in different working states, so that the sleep current of the vehicle-mounted multimedia system is effectively reduced, and the AM radio signal is ensured not to be interfered; the power regulating circuit comprises a resistor, a triode or an NMOS tube, has a simple structure, does not need special devices and has high cost; the service life of the vehicle-mounted storage battery is prolonged, premature feeding of the storage battery is prevented, and circuit elements of vehicle-mounted multimedia are effectively protected.
In some embodiments of the present application, the power conditioning circuit 4 includes a first resistor R1, a second resistor R2, and a transistor Q1, wherein the first resistor R1 and the second resistor R2 are both connected in parallel to the voltage output terminal FREQ of the switching circuit 2, the other end of the first resistor R1 is connected to the collector of the transistor Q1, and the other end of the second resistor R2 is connected to ground. The base electrode of the triode Q1 is connected to the signal output end MCU _ GPIO of the main control chip 3, and the emitter electrode of the triode Q1 is grounded. A first parasitic resistor is connected between the base electrode of the triode Q1 and the signal output end MCU _ GPIO, and a second parasitic resistor is connected between the emitter electrode and the base electrode of the triode Q1. Referring to table 1, table 1 is a relationship diagram of a FREQ connection resistance and a working frequency of a voltage output terminal FREQ of a switch chip U1 in the switch circuit 2 of the present embodiment, and in order to solve the problem of interference on a radio module, a switching frequency is generally set to 2200 KHz; the frequency range of the middle wave band of the radio AM is 531 KHz-1602 KHz. In this embodiment, the resistance of the first resistor R1 is 27K Ω, the resistance of the second resistor R1 is 80K Ω, the parallel resistance of the first resistor R1 and the second resistor R2 is 20K Ω, when the vehicle-mounted multimedia system normally works, the signal output end MCU _ GPIO of the main control chip 3 is high level, at this time, the triode Q1 is turned on, the power regulating circuit is turned on, so that when the first resistor and the second resistor are connected in parallel at the voltage output end FREQ of the switch chip U1, the frequency of the switch circuit is 2200 KHz; when on-vehicle multimedia system gets into sleep mode, main control chip 3 is in dormant state, signal output part MCU _ GPIO control signal defaults to low level, triode Q1 is closed, second resistance R2 directly links the voltage output part FREQ resistance at switch chip U1 this moment and is 80K omega, thereby make the switching circuit frequency that corresponds be 500KHz, because of the system is in dormant state, 500 KHz's operating frequency and relevant doubling of frequency can not influence the work of radio module circuit, thereby can reduce the efficiency of switching power supply's of on-vehicle multimedia system when the dormancy operating frequency promotes the power through this control circuit, can reduce former sleep current at most 30% again.
In some embodiments of the present application, the power regulation circuit 4 includes a first resistor R1, a second resistor R2, and an NMOS transistor, the first resistor R1 and the second resistor R2 are both connected in parallel to the voltage output terminal FREQ of the switch circuit 2, the other end of the first resistor R1 is connected to the drain of the NMOS transistor, and the other end of the second resistor R2 is connected to ground. The grid electrode of the NMOS tube and the signal output end MCU _ GPIO of the main control chip 3 are grounded.
Referring to table 1 in the above, table 1 is a relationship diagram of the FREQ connection resistance and the operating frequency of the voltage output terminal FREQ of the switch chip U1 in the switch circuit 2 of this embodiment, and in order to solve the problem of interference on the radio module, the switching frequency is generally set to 2200 KHz; the frequency range of the middle wave band of the radio AM is 531 KHz-1602 KHz. In this embodiment, the resistance of the first resistor R1 is 27K Ω, the resistance of the second resistor R1 is 80K Ω, and the parallel resistance of the first resistor R1 and the second resistor R2 is 20K Ω, when the vehicle-mounted multimedia system normally works, the signal output end MCU _ GPIO of the main control chip 3 is high level, at this time, the NMOS transistor is turned on, the power regulating circuit is turned on, so that when the first resistor and the second resistor are connected in parallel at the voltage output end FREQ of the switch chip U1, the frequency of the switch circuit is 2200 KHz; when on-vehicle multimedia system got into sleep mode, main control chip 3 was in dormant state, signal output part MCU _ GPIO control signal defaults to low level, the NMOS pipe is closed, second resistance R2 directly links the voltage output part FREQ resistance that is at switch chip U1 this moment and is 80K omega, thereby make the switching circuit frequency that corresponds be 500KHz, because of the system is in dormant state, 500 KHz's operating frequency and relevant doubling of frequency can not influence the work of radio module circuit, thereby can reduce the operating frequency of on-vehicle multimedia system switching power supply when the dormancy through this control circuit and promote the efficiency of power, can reduce former sleep current at most 30% again.
In some embodiments of the present application, the second resistor R2 is greater than the first resistor R1; when the vehicle-mounted multimedia system works normally, the frequency of the switching circuit is higher than the frequency range of the middle wave band of the radio AM; when the vehicle-mounted multimedia system enters a sleep mode, the frequency of the switch circuit is lower than the frequency range of the middle wave band of the radio AM; in the present embodiment, the first resistor R1 and the second resistor R2 are not limited to the first resistor R1 having a resistance of 27K Ω and the second resistor R2 having a resistance of 80K Ω provided in the above embodiments; embodiments satisfying that the second resistor R2 is larger than the first resistor R1 fall within the scope of the present application.
In some embodiments of the present application, the switching circuit 2 is a DC-DC buck type circuit; the switch circuit 2 comprises a switch power supply chip U1, and the power supply input end Vin of the vehicle-mounted storage battery 1 and the switch power supply chip U1 is sequentially connected with a diode, an inductor, at least one capacitor and at least one resistor; the power output end Vout of the switching power supply chip U1 is connected with the main control chip 3 sequentially through the inductor, the at least one capacitor and the at least one resistor. In the present embodiment, the DC-DC buck circuit is one of DC/DC converters, and the DC/DC converter is a voltage converter that effectively outputs a fixed voltage after converting an input voltage. DC/DC converters are divided into three categories: a step-up DC/DC converter, a step-down DC/DC converter, and a step-up/step-down DC/DC converter. Three types of control can be used as required. The PWM control type is efficient and has good output voltage ripple and noise. The PFM control type has an advantage of low power consumption even when used for a long time, particularly when used under a small load. The PWM/PFM switching type PFM control is carried out at the time of a small load, and is automatically switched to the PWM control at the time of a heavy load. In this embodiment, any DC/DC converter capable of reducing the incoming voltage of the battery may be adopted, and a diode, an inductor, a capacitor and a resistor are connected between the vehicle-mounted battery 1 and the power input terminal Vin of the switching power supply chip U1, and are used for preventing reverse, filtering and stabilizing voltage of the switching circuit 2. The power output end Vout of the switching power supply chip U1 is connected with the main control chip 3 sequentially through an inductor, five capacitors and four resistors and is used for preventing reverse, filtering and stabilizing voltage of the switching circuit 2.
In some embodiments of the present application, an LDO linear power supply circuit 4 is further included, and the LDO linear power supply circuit 4 is connected between the switch circuit 2 and the main control chip 3. The LDO linear power supply circuit 4 is one of linear voltage-stabilized power supplies, which are dc voltage-stabilized power supplies used earlier. According to the working state of the regulating tube, voltage-stabilizing power supplies are often divided into two categories: linear regulated power supplies and switching regulated power supplies. The linear voltage-stabilizing direct-current power supply is characterized in that: the output voltage is lower than the input voltage; the reaction speed is high, and the output ripple is small; the noise generated by the work is low; the efficiency is low, and the LDO adopted by the application is used for solving the efficiency problem; if the heat productivity is large, the thermal noise is indirectly added to the system.
According to the circuit for reducing the sleep current of the vehicle-mounted multimedia system, the power regulating circuit is arranged to control the working frequency of the switching circuit in different working states, so that the sleep current of the vehicle-mounted multimedia system is effectively reduced, and an AM radio signal is ensured not to be interfered; the power regulating circuit comprises a resistor, a triode or an NMOS tube, has a simple structure, does not need special devices and has high cost; the service life of the vehicle-mounted storage battery is prolonged, premature feeding of the storage battery is prevented, and circuit elements of vehicle-mounted multimedia are effectively protected.
The embodiments of the present application have been described in detail with reference to the drawings, but the present application is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present application within the knowledge of those skilled in the art.
Claims (10)
1. A circuit for reducing the sleep current of a vehicle-mounted multimedia system is characterized by at least comprising a vehicle-mounted storage battery (1), a switch circuit (2), a power regulating circuit (4) and a main control chip (3), wherein the vehicle-mounted storage battery (1) is connected with the main control chip (3) through the switch circuit (2); the voltage input end of the power regulating circuit (4) is connected with the voltage output end (FREQ) of the switch circuit (2), the signal input end of the power regulating circuit (4) is connected with the signal output end (MCU _ GPIO) of the main control chip (3), and the power regulating circuit (4) controls the power of the switch circuit (2) by receiving the level signal from the main control chip (3).
2. The circuit for reducing the sleep current of the car multimedia system according to claim 1, wherein the power regulating circuit (4) comprises a first resistor (R1), a second resistor (R2), and a transistor (Q1), the first resistor (R1) and the second resistor (R2) are connected in parallel to the voltage output terminal (FREQ) of the switch circuit (2), the other end of the first resistor (R1) is connected to the collector of the transistor (Q1), and the other end of the second resistor (R2) is connected to ground.
3. The circuit for reducing the sleep current of the car multimedia system according to claim 2, wherein the base of the transistor (Q1) is connected to the signal output terminal (MCU _ GPIO) of the main control chip (3), and the emitter of the transistor (Q1) is grounded.
4. The circuit for reducing the sleep current of the car multimedia system according to claim 3, wherein a first parasitic resistor is further connected between the base of the transistor (Q1) and the signal output terminal (MCU _ GPIO), and a second parasitic resistor is connected between the emitter and the base of the transistor (Q1).
5. The circuit for reducing the sleep current of the vehicle-mounted multimedia system according to claim 1, wherein the power regulating circuit (4) comprises a first resistor (R1), a second resistor (R2), and an NMOS transistor, the first resistor (R1) and the second resistor (R2) are connected in parallel to the voltage output terminal (FREQ) of the switch circuit (2), the other end of the first resistor (R1) is connected to the drain of the NMOS transistor, and the other end of the second resistor (R2) is connected to ground.
6. The circuit for reducing the sleep current of the vehicle-mounted multimedia system according to claim 5, wherein the gate of the NMOS transistor is connected to the signal output terminal (MCU _ GPIO) of the main control chip (3), and the source is grounded.
7. The circuit for reducing the sleep current of the vehicle-mounted multimedia system according to any one of claims 2 or 5, wherein the second resistor (R2) has a larger resistance value than the first resistor (R1).
8. The circuit for reducing the sleep current of the vehicle multimedia system as claimed in claim 1, wherein the switching circuit (2) is a DC-DC buck circuit.
9. The circuit for reducing the sleep current of the vehicle-mounted multimedia system according to claim 8, wherein the switch circuit (2) comprises a switch power chip (U1), and the power input end (Vin) of the vehicle-mounted storage battery (1) and the switch power chip (U1) are sequentially connected with a diode, an inductor, at least one capacitor, at least one resistor; and a power output end (Vout) of the switching power supply chip (U1) is connected with the main control chip (3) sequentially through an inductor, at least one capacitor and at least one resistor.
10. A circuit for reducing sleep current in a vehicle multimedia system according to claim 1, further comprising an LDO linear power supply circuit (4), wherein the LDO linear power supply circuit (4) is connected between the switch circuit (2) and the main control chip (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921054147.3U CN210201711U (en) | 2019-07-08 | 2019-07-08 | Circuit for reducing sleep current of vehicle-mounted multimedia system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921054147.3U CN210201711U (en) | 2019-07-08 | 2019-07-08 | Circuit for reducing sleep current of vehicle-mounted multimedia system |
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| CN210201711U true CN210201711U (en) | 2020-03-27 |
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| CN201921054147.3U Active CN210201711U (en) | 2019-07-08 | 2019-07-08 | Circuit for reducing sleep current of vehicle-mounted multimedia system |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111746348A (en) * | 2020-06-30 | 2020-10-09 | 德尔福科技(苏州)有限公司 | Battery management system contactor control system and method |
| CN112994167A (en) * | 2021-03-19 | 2021-06-18 | 维沃移动通信有限公司 | Charging device, electronic apparatus, charging control method, and charging control device |
-
2019
- 2019-07-08 CN CN201921054147.3U patent/CN210201711U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111746348A (en) * | 2020-06-30 | 2020-10-09 | 德尔福科技(苏州)有限公司 | Battery management system contactor control system and method |
| CN112994167A (en) * | 2021-03-19 | 2021-06-18 | 维沃移动通信有限公司 | Charging device, electronic apparatus, charging control method, and charging control device |
| CN112994167B (en) * | 2021-03-19 | 2024-10-15 | 维沃移动通信有限公司 | Charging device, electronic apparatus, charging control method, and charging control device |
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