Patent ID: 8179649
Filing Date: 2012-05-15
Classification: G09G

Abstract:
1. A protection circuit for a control board, the protection circuit being connected to a light on tester, wherein the light on tester outputs a test voltage to a display module, the protection circuit comprising: a control device, comprising a first switching element and a control element, wherein the control element is electrically connected to the first switching element, and enables the first switching element to output an operating voltage; and a voltage stabilizer, comprising a second switching element and an operation module, wherein the second switching element is electrically connected between the display module and the light on tester, and the operation module controls the second switching element according to the operating voltage, so as to switch on or switch off an input of the test voltage to the display module, wherein the operation module comprises an operational amplifier and a voltage stabilizing element electrically connected to the operational amplifier, the voltage stabilizing element modulates the operating voltage into a reference voltage, and the operational amplifier controls a voltage value of the test voltage input to the display module according to the reference voltage and a feedback from the test voltage.