BenQ Q7T4-FP71G, Service Manual

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Q7T4-FP71G LCD Monitor Service Guide
Circuit Operation Theory
1
Confidential
I. Introduction:
The Q7T4 is a 17” SXGA (1280x1024) , 16.2M colors(R, G, B 6-bit data+FRC data) TFT
LCD monitor. It’s an analog only interface LCD monitor with a 15 pins D-sub signal cable. it’s
compliant with VESA specification to offer a smart power management and power saving function. It
also offers OSD menu for users to control the adjustable items and get some information about this
monitor, and the best function is to offer users an easy method to set all adjustable items well just by
pressing one key, we called it “Auto key” which can auto adjusting all controlled items. Q7T4 also
offer DDC2 function to meet VESA standard.
II. Block diagram
The Q7T4 consists of a LCD module with 4 lamps, an power board, a control board ,and a
interface BD. The block diagram is shown as below.
III. Circuit operation theory:
A-1.) Interface board diagram:
Control board
Interface board
LCD module with 4 lamps (backlight)
AC power in
D-Sub
Inverter
Power