Seat fan control integrated circuit

Abstract

The utility model provides a kind of seat fan control integrated circuit, and the seat fan control integrated circuit can realize input voltage filtering common mode noise and input and output bidirectional noise suppression by filtering protection circuit;When input voltage overvoltage, automatically shut off input voltage, protect fan motor by overvoltage protection circuit;Prevent input PWM noise and voltage peak interference by PWM protection circuit, play steady fan work;Fan stable work can be realized by fan motor drive circuit.

Description

Technical Field

[0001] This utility model belongs to the field of automotive seat fan circuit technology, and in particular relates to a seat fan control integrated circuit. Background Technology

[0002] With the increasing popularity of automobiles, consumers have higher and higher demands. Besides price, people are paying more attention to vehicle safety and comfort. Zero-gravity seats are not only key to improving passenger comfort, but also crucial technologies for developing high-quality car seats and establishing market competitiveness. This invention designs a seat fan control integrated circuit that enables adjustable seat fan speed, overvoltage protection, and surge protection. Utility Model Content

[0003] This invention provides a seat fan control integrated circuit, which aims to solve the problems mentioned in the background art.

[0004] This utility model is implemented as follows: a seat fan control integrated circuit includes a filter protection circuit, an overvoltage protection circuit, a PWM protection circuit, and a fan motor drive circuit.

[0005] The filtering protection circuit includes a transient voltage suppression diode, a common-mode inductor, a Π-type filter circuit, and a diode. The transient voltage suppression diode is used to suppress transient high-voltage spike pulses, the common-mode inductor is used to suppress common-mode noise, the Π-type filter circuit is used to suppress bidirectional noise, and the diode is used to prevent reverse power supply.

[0006] The overvoltage protection circuit achieves overvoltage shutdown when the voltage exceeds the rated voltage.

[0007] The PWM protection circuit is used to achieve high voltage isolation of the PWM pulse width and filter out noise signals.

[0008] The fan motor drive circuit includes a fan drive chip, which is used to adjust the output power and wind speed of the fan.

[0009] Preferably, the rated voltage in the overvoltage protection circuit is 9-16V.

[0010] Preferably, the overvoltage protection circuit includes a transistor and a MOSFET, wherein the transistor is an MMBT3906.

[0011] Preferably, the PWM protection circuit includes a PWM_IN port and a PWM port, and the PWM pulse width waveform output by the vehicle domain controller enters the PWM protection circuit from the PWM_IN port.

[0012] Preferably, the fan driver chip includes pins 1, 2, 3, 4, and 5. Pins 2 and 5 supply power to the fan driver chip, pin 1 receives the PWM pulse width wave input from the PWM protection circuit, and pins 3 and 4 are connected to the fan motor.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] This seat fan control integrated circuit can filter out common-mode noise and suppress bidirectional noise in both input and output through a filter protection circuit; it can automatically shut off the input voltage to protect the fan motor when the input voltage is too high through an overvoltage protection circuit; it can prevent input PWM noise and voltage spike interference through a PWM protection circuit to stabilize the fan operation; and it can ensure stable fan operation through a fan motor drive circuit. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the filter protection circuit in this utility model;

[0016] Figure 2 This is a schematic diagram of the overvoltage protection circuit in this utility model;

[0017] Figure 3 This is a schematic diagram of the PWM protection circuit in this utility model;

[0018] Figure 4 This is a schematic diagram of the fan motor drive circuit in this utility model. Detailed Implementation

[0019] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0020] The components of the present invention embodiments described and shown in the accompanying drawings can typically be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0021] Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0022] Please see Figures 1 to 4 This utility model provides a technical solution: a seat fan control integrated circuit, including a filter protection circuit, an overvoltage protection circuit, a PWM protection circuit, and a fan motor drive circuit;

[0023] See appendix Figure 1 The filter protection circuit includes a transient voltage suppression diode TVS1, a common mode inductor CL1, a Π-type filter circuit, and a diode D1. TVS1 is used to suppress transient high voltage spike pulses, CL1 is used to suppress common mode noise, the Π-type filter circuit consists of a ferrite bead, C1 and C2, and is used to suppress bidirectional noise at both input and output, and diode D1 is used to prevent reverse power connection.

[0024] See appendix Figure 2 The control method of the overvoltage protection circuit is as follows: When the input voltage is within the rated voltage range (9-16V), Q1 (transistor MMBT3906) is not turned on, and MOSFET (MOS1: NCE40P0Y) is turned on, outputting the rated operating voltage (OverVoltage_VCC); when the input voltage exceeds the rated voltage (greater than 17V), Q1 is turned on, and the source S of the MOSFET is about 0.3V greater than the gate G (transistor Q1 is turned on, and the voltage at the emitter E is about 0.3V greater than the voltage at the collector C), so the MOSFET is turned off and does not conduct (the conduction voltage drop between V and Sg is about 2V, and a 0.3V voltage drop difference means no conduction), so there is no operating voltage output, achieving the overvoltage shutdown function;

[0025] See appendix Figure 3 The PWM protection circuit control method is as follows: The vehicle domain controller outputs a PWM pulse width waveform (high level greater than 5V) which enters from the PWM_IN port. The TVS transistor TVS2 filters out high voltage spike pulses, and the interference noise is filtered out by an LC filter composed of a ferrite bead and C3. When the PWM_IN port is a low-level pulse, Q2 is turned on, outputting a high-level pulse (3V) to the PWM port. When the PWM_IN port is a high-level pulse, Q2 is not turned on, and the PWM port is a low-level (0V) pulse signal. In this way, the purpose of PWM pulse width high voltage isolation and filtering of noise signals is achieved.

[0026] See appendix Figure 4 The fan drive circuit is composed of a fan drive chip (MLX90411KLD). Pins 2 and 5 are powered by the Over Voltage_VCC voltage and GND, respectively. Pin 1 receives the PWM pulse width wave input from the PWM protection circuit. Pins 3 and 4 are connected to the fan motor. The duty cycle of the fan is adjusted by inputting the PWM pulse width wave from pin 1, thereby adjusting the output power and wind speed of the fan.

[0027] When the seat fan is powered on, the input voltage is transformed into a stable supply voltage through a filter protection circuit. This stable supply voltage is then supplied to the fan's driver chip. The vehicle domain controller provides the driver chip with PWM pulse width modulation, which changes the fan's output power and thus alters the fan speed.

[0028] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A seat fan control integrated circuit, characterized in that: Includes filter protection circuit, overvoltage protection circuit, PWM protection circuit and fan motor drive circuit; The filtering protection circuit includes a transient voltage suppression diode, a common-mode inductor, a Π-type filter circuit, and a diode. The transient voltage suppression diode is used to suppress transient high-voltage spike pulses, the common-mode inductor is used to suppress common-mode noise, the Π-type filter circuit is used to suppress bidirectional noise, and the diode is used to prevent reverse power supply. The overvoltage protection circuit achieves overvoltage shutdown when the voltage exceeds the rated voltage. The PWM protection circuit is used to achieve high voltage isolation of the PWM pulse width and filter out noise signals. The fan motor drive circuit includes a fan drive chip, which is used to adjust the output power and wind speed of the fan.

2. The integrated circuit for controlling a seat fan according to claim 1, characterized in that: The rated voltage in the overvoltage protection circuit is 9-16V.

3. The integrated circuit for controlling a seat fan according to claim 2, characterized in that: The overvoltage protection circuit includes a transistor and a MOSFET, wherein the transistor is an MMBT3906.

4. The integrated circuit for controlling a seat fan according to claim 1, characterized in that: The PWM protection circuit includes a PWM_IN port and a PWM port. The PWM pulse width waveform output by the vehicle domain controller enters the PWM protection circuit through the PWM_IN port.

5. The integrated circuit for controlling a seat fan according to claim 1, characterized in that: The fan driver chip includes pins 1, 2, 3, 4, and 5. Pins 2 and 5 supply power to the fan driver chip. Pin 1 receives the PWM pulse width waveform input from the PWM protection circuit. Pins 3 and 4 are connected to the fan motor.

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