Erbe ICC 200, Руководство по обслуживанию

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3 CIRCUIT DESCRIPTION
Target memory and drivers for rows and columns of the display matrix
The LED matrix is actuated by the already described internal bus system B1BUS of the display board.
The 8-fold D-flipflops IC2, IC3 and IC12 are used as target memories for columns (IC2) and rows (IC3).
The columns of the lamp matrix LS1 to LS6 are activated via the driver transistors T2, T20, T11, T10, T4
and T9 switched as emitter followers in a multiplex method and each switched for a brief time to +5 volts.
The current is then led via the appropriate LED and directed via the necessary current limitation resistors as
well as the transistor array IC4 to chassis.
The blue LEDs D36 and D37 for display of the coagulation channels are an exception, the anodes of which
are permanently at +5 volts via the current limitation resistors and are switched on via the transistor array
IC13.
Jumpers for activation of special software
Jumpers J3 to J10 are intended for software specialities available for tests and for switching on special
features in certain countries. The corresponding jumpers are already placed during production and must not
be changed arbitrarily.
Display board