Development Bias Circuit - Ricoh A219 Service Manual

DEVELOPMENT

5.5 DEVELOPMENT BIAS CIRCUIT

Main Board
24 V
C N 1 0 2 - 7
G N D
C N 1 0 2 - 6
C Trigger
C N 1 0 2 - 5
T Trigger
C N 1 0 2 - 4
B - P W M
C N 1 0 2 - 3
S Trigger
C N 1 0 2 - 2
5 V
4.7 k
C N 1 0 2 - 1
The main board supplies +24 volts to the high voltage supply board from
CN102-7. When the ! key is pressed, the CPU starts sending the bias
trigger pulses from CN102-3. This energizes the development bias circuit
within the high voltage supply board, which applies a high negative voltage to
the development roller. The development bias is applied whenever the drum
is rotating.
A219
CÓPIA NÃO CONTROLADA
High Voltage Supply Board
D C / D C
Converter
D C / D C
Converter
D C / D C
Converter
Zener
Diode
D C / D C
Converter
Protection
Circuit
2-24
CÓPIA NÃO CONTROLADA
G C
Drum
B
S
T
A219D506-2.wmf
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