Circuit Operation Theory - Acer G225HQ Service Manual

6.2 Circuit Operation Theory

I. Introduction:
G225HQ is a 21.5 inch and 24bits color TFT LCD monitor, which can support the resolution up to 1920x1080. It
has VGA input and compliant with VESA specification to offer a smart power management. The monitor has
DDC/CI function to make the monitor communicate with PC by Acer ADM DDC/CI software, and also it has
ACM function to let the monitor contrast ratio up to 50000:1. It also offers OSD Menu for users to control the
adjustable items and get some information about this monitor.
II. Block diagram
G225HQ consists of a main body and a stand (base). The main body contains a AUO/LGD TFT
LCD module with 4 CCFL lamps, a power board (includes AC/DC 、 DC/DC 、 inverter and
panel power source), a control board and an interface board. The block diagram is shown as
below.
Fig. Block diagram for G225HQ LCD monitor
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