GE Brivo OEC 715 - Keyboard Control Board

System Overview
2-35
Keyboard Control Board
The Keyboard Control Board is installed in the Workstation and acted as the translator between workstation
membrane keyboard and workstation computer.
It translates key press and release into make/break code that computer can identify. The interface and
communication between KCB and computer conforms to standard USB 1.1 protocol.
The structure of KCB is shown as follows:
Power and USB signal
The keyboard control board connects
with the host computer of WKS by a
USB cable; the power and signal
conform to the standard USB 1.1
protocol.
Key matrix interfaces
The keyboard control board
connects with key membrane by
flexible flat cable; every scan wire in
flexible cable is protected by TVS
diode, which is realized by adding
TVS diode array chips, SP723AG in
the keyboard control board.
Power
and
communi
cation
interface
TVS
protection
LED
indicator
Keyboard
decoder
Keyboard
scan line
interface
Keyboard Control Board