JPM MPS2, Руководство пользователя

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TECHNICAL DESCRIPTION
15 Digit Driver Board
This board is capable of driving up to 15 seven segment displays, all displays are bussed with their common
cathode connections switched by the sink transistors trom the MP8 1 multiplexer array, thereby torming a
separate display matrix.
The board carries the sink & source connections as weil as the control ~ircuitry tor the 15 digit display. The
source 8010-8015, sink 810-815 connections are brought onto the board via edge connectors A & B respectively,
then transferred to the display board via diodes 08-028 & lOC connector H01.
Sink lines 810-8114 are used to strobe the digits on the display board. As each digit is strobed, the corresponding
BCO data is output via tour direct outputs OP2-0P5 & presented to the board edge connector A. This information
is decoded by IC1 (MC 14511) a BCO to 7 segment decoder chip. The output of the MC 14511 is transmitted to
the segments of the L.E.O.'s via IC2 (UON 2981 A) a high current source driver chip and 7 x 68R 1 watt current
limiting resistors.
15 Digit Display Board
This board can be loaded with up to 15 seven segment displays (L T8 6780R) in three groups of 5, it also has
provision tor the insertion of up to six 12v 1 w lamps. Each 12v lamp is held in a twist 'n' lock holder fitted into
holes in the PCB.
All drive circuitry tor this board is contained on the 15 digit driver board (045152) and all interconnections are
made using a 40 way ribbon cable assembly 080053 terminated onto the board at H01.
2 Digit Display Board
This board is loaded with two 7 segment displays (L T 1723R). The board is connected to a push in 20 way edge
connector and is driven by multiplexing of the MP81 and MP82 main boards.
8 Digit Display Driver Board
This board can drive up to tour 1 " 2 digit display pcb's. The board contains a 40 way header W1 which is fed
direct I y trom the multiplexing circuitry on the MP81 or MP82 main boards. There are also tour 12 way headers
W2 -W5, each header driving one 2 digit display. This board also contains additional multiplexing components
R1 -R16 and 01- 020.
1"-2 Digit Display Boards
Each board comprises of 2 x L T81723R seven segment common cathode displays and one 10 way header W1.
The displays are driven direct I y trom the 8 digit display driver pc b via W1 .