This is a brand new substitute inverter module. By analysis the failure of the original inverter, our engineers had come up with a better circuit design which is a lot more dependable. 90 Days Warranty. Note: LS520A is using a negative control for enable. So, P5 should be 0V when LS520 is on. It depends on type of the LCD controller boards, in case LS520 is not working, be sure connect P5 to ground,
