The image of a Skyworth LCD TV 26S19IW is very light and the sound is normal. Suspicion is a logic board problem. The logic board is not separate, but is connected to the screen. When the screen is opened, the long logic board is seen. The measured GM1 is 11.3V, the GM2 is 11V, the GM3 is 9.2V, the GM4 is 12.2V, and the GM5 is 8.3V. GM6 is 7.5V, GM7 is 6.6V, GM8 is 6.0V, GM9 is 5,1V, GM10 is 4.4V, GM11 is 4V, GM12 is 3.4V, GM13 is 1.5V. Only GM4 does not meet the ladder power, GM4 It is provided by U10 (EC48324-FV). Check some information and remove U10. The GM4 voltage is 8.63V, which is normal. Use 43K and 36K to divide the voltage between the power supply (13.3V) and the ground, and the midpoint is connected to VCM (6V). It works normally (only the image is a little white when it is just turned on, and generally cannot be seen). Silicon TVS / TSS:
Diode TVS (Transient Voltage Suppressor), also known as Transient suppression diodes, is widely used a new type of high efficient circuit protection device, it has a fast response time (the nanosecond) and high surge absorbing ability.When it ends of stand moments of high energy shock, TVS can bring the two ends at high rate from high impedance to a low impedance between impedance values, to absorb a large current moment, put it at both ends of the voltage restraint on a predetermined value, thus protecting the back of the circuit components are not affected by the impact of the transient high pressure spikes.
Silicon TVS Transient Voltage Suppresso,Silicon TSS Transient Voltage Suppresso YANGZHOU POSITIONING TECH CO., LTD. , https://www.pst-thyristor.com
March 25, 2023