Samsung SF6500 Service Manual page 77

Circuit Description
5-10 Second Cassette Feeder (Option)
This circuit contains:
-motor driver consisted of motor drive IC(UDN2916B), MC14040 binary counter, and peripheral filp-flop;
-paper empty sensor;
-paper feeding clutch controller; and
-interface signal controller.
The 480 kHz resonator generates 373 pps motor phase using the binary counter to drive the motor.
SCF I/O Control Signal
Pin no. Pin name
CN1-2 SCF_SEL
CN1-3 SCFMTRSTRT SCF motor start
CN1-4 SCFCLTCH
CN1-5 SCFPEMPT
5-8
Description Status
SCF select L: SCF
L: start
SCF clutch control H: paper feed
SCF paper empty L: no paper
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