Lp 644-4 Display Board (Hep) - Fresenius Medical Care 4008 E Technical Manual

8.20 P.C.B. LP 644-4 Display board (HEP)
8.20.1 Description
General information
P.C.B. LP 644-4 comprises the elements for the display and the operating keyboard. All elements
are covered by a water-tight foil.
Display
All of the information required is given to the user by three seven-segment displays and two
LEDs.
Keyboard
The keyboard comprises six individual make contacts, which are directly soldered into the printed
circuit board. These contacts constitute a 2x3 matrix and are directly connected to and evaluated
by the gate array.
Fresenius Medical Care 4008 4/09.03 (TM)
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