Brother HL-1870N, Service Manual

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HL-1850/1870N SERVICE MANUAL
3-15
1.4 Engine PCB
The gate array which transforms the serial signal from the main PCB into the parallel signal is
mounted on the engine PCB.
The engine PCB controls the following parts by using the transferred signal data;
•
Main motor
•
Lower cassette sensor
•
Fan motor
•
Upper paper exit sensor
•
Thermistor
•
Lower paper exit sensor
•
Polygon motor
•
Duplex tray sensor
•
Solenoid
•
Duplex lever sensor
•
HIgh-voltage power supply
•
Duplex cover sensor
•
Toner sensor
•
Lower cassette exit sensor
•
Cover sensor
•
Paper eject sensor
•
Front registration sensor
•
Fixing unit cover sensor
•
Rear registration sensor
•
Multi-purpose tray paper exit sensor
•
Upper cassette sensor
For the circuit diagram of the engine PCB, see APPENDIX 8. and 9. ‘ENGINE PCB CIRCUIT
DIAGRAM, HL-1850/1870N’ in this manual.
1.5 BR-net PCB
The BR-net PCB is connected to the ASIC mounted on the main PCB through the PCI bus.
The Ethernet controller, AM79C973AKC is mounted on the BR-net PCB. The controller
incorporates the 10/100 Mbps physical interface which conforms to IEEE 802.3 and is
connected with the external Ethernet through the RJ-45 connector.
For the circuit diagram of the BR-net PCB, see
APPENDIX 10. ‘NETWORK BOARD PCB
CIRCUIT DIAGRAM, HL-1850/1870N’ in this manual.