A kind of fault detection circuit and method of led automobile turn signal lamp

Abstract

A LED automobile turn signal fault detection circuit and method thereof, including a test circuit and a test method. The test circuit includes a fault detection feedback circuit and a fault detection circuit. The fault detection circuit includes: IN_LED terminal, R1 resistor, R2 resistor, R3 resistor, capacitor C, VBAT power supply terminal and OUT_BCM terminal. The fault detection feedback circuit includes an LED turn signal externally connected to the IN_LED terminal of the fault detection circuit, and a body controller BCM connected to the OUT_BCM terminal through a feedback line. The present invention judges the fault condition of the LED turn signal by identifying whether the IN_LED terminal is in a high-impedance state and the level state of the front and rear feedback lines. The invention does not need an intelligent detection chip, has low manufacturing cost and accurate fault detection.

Description

technical field [0001] The invention relates to the field of automobile electronics, in particular to an LED automobile turn signal fault detection circuit and a method thereof. Background technique [0002] With the continuous development of LED technology and the reduction of cost, LED lights are more and more used in automobiles. In order to ensure the safety of the car in the process of driving, the law stipulates that the turn signal of the car must be checked for faults from time to time, and a warning will be issued to avoid driving hazards caused by damage to the turn signal. But the detection method of the traditional turn signal is not suitable for LED fault detection. The traditional turn signal has high power, so its current changes greatly after power failure or failure, and the intelligent power chip can be used to obtain the fault information by detecting the feedback current. CN102452352 discloses "a detection control circuit and detection method of an LED ...

AI Technical Summary

Problems solved by technology

However, the power of LED lights is low, the current change after power failure or failure is small, and it is easily covered by the change of vehicle level voltage and the noise on the transmission path of the detection circuit, etc., so the fault cannot be accurately judged. A new fault detection method, the detection module circuit of this detection method should be simple and easy to implement, low in cost, and easy to realize cost control of the whole vehicle

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