Page 2.7
Chapter 2
Functional Overview
SCHILLER AT-2plus 6-Channel ECG Unit
SERVICE HANDBOOK Issue d May 2002
Top Assembly
LCD Screen
The LCD power supply produces the high voltage for the LCD backlight and the contrast voltage.
The ECG signals are stored in a video RAM and the LCD controller converts the data to the
proper form for the LCD screen.
Alphanumerical Keyboard
The keyboard is a matrix style circuit which is periodically scanned by the processor via the
keyboard interface circuit. It is an integral part of the top assembly and can not be individually
replaced.