Fault phenomenon: Hisense LED40K160JD LCD TV boot backlight is bright, with sound.
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Fault analysis: the backlight is bright, there is sound, indicating that the voltage board and the motherboard should be normal; focus on checking the logic board and the screen circuit
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Voltage at test point failure (V) Normal voltage (V)
VIN 12 12
VDD 3.3 3.3
VDD 1.2 1.2
VONE 1.5 swings around 30 (logic board marked 28V)
VOFFE -1V swings around -11
AVDD 0.02 17.5
VMHL 2.5 7.5
Fault detection: Since the logic board has several voltages that are abnormal (too low) and there is a suspected short circuit, use the resistance file to measure and find AVDD.
This road is obviously short-circuited, using the "burning chicken" Dafa. Digital DC power supply adjustment 2V, found that the current is more than 2A, the hand touched the suspected short-circuit original, found that the CD11 chip capacitor has obvious heat, then remove the measurement has been short-circuited, then measure AVDD
Short circuit is eliminated, replace this capacitor, and troubleshoot.
A gas sensor is a converter that converts a certain gas volume fraction into a corresponding electrical signal. The detector head regulates the gas sample through the gas sensor, usually including filtering impurities and interfering gas, drying or refrigeration, and processing the instrument display part.
Gas sensor is a device that converts the information of gas composition and concentration into information that can be used by personnel, instruments, computers, etc! Gas sensors are generally classified as chemical sensors, although this classification is not necessarily scientific.
Gas Sensor,Gas Flow Sensor,Gas Detector Sensor,Ultrasonic Gas Sensor
Taizhou Jiabo Instrument Technology Co., Ltd. , https://www.taizhoujiabo.com