Brother P-touch QL-1050 Service Manual page 4

2.3 MAIN PCB ................................................................................................................. II-8
2.3.1 Logic Components ............................................................................................. II-9
[ 1 ] CPU ................................................................................................................ II-9
[ 2 ] Flash ROM...................................................................................................... II-9
[ 3 ] SDRAM ........................................................................................................... II-9
[ 4 ] EEPROM ........................................................................................................ II-9
2.3.2 Key, LED Circuit................................................................................................. II-10
2.3.3 Head and Motor Power Supply ON/OFF Circuit................................................ II-11
2.3.4 Full Cutter Motor Driver Circuit and Media Feed Motor Driver Circuit............... II-12
2.3.5 Media Type Sensor Circuit, Media Position Detect Sensor Circuit
and Cover Open Sensor Circuit ........................................................................ II-13
2.3.6 Head Temperature Detect Circuit ...................................................................... II-16
2.3.7 Cutter Home Position Sensor Circuit ................................................................. II-16
2.3.8 Reset Circuit ...................................................................................................... II-16
2.3.9 USB Interface Circuit ......................................................................................... II-17
2.3.10 RS232C Interface Circuit ................................................................................... II-17
CHAPTER III DISASSEMBLY AND REASSEMBLY.......................................... III-1
3.1 SAFETY PRECAUTIONS ......................................................................................... III-1
3.2 TIGHTNING TORQUE LISTS................................................................................... III-2
3.3 LUBRICATION POINTS LIST................................................................................... III-3
3.4 DISASSEMBLY PROCEDURE................................................................................. III-5
[ 1 ] Removing the Top Cover ASSY and Thermal Tape ...................................... III-5
[ 2 ] Disassembling the Top Cover ASSY.............................................................. III-7
[ 3 ] Removing the Upper Cover ASSY ................................................................. III-9
[ 4 ] Removing the Power Supply PCB and Main PCB.......................................... III-12
[ 5 ] Removing the Front Cover, Panel Cover and Front Side Cover .................... III-16
[ 6 ] Removing the Cutter Unit ASSY and Mecha ASSY ....................................... III-18
[ 7 ] Disassembling the Panel Cover ..................................................................... III-19
[ 8 ] Disassembling the Mecha ASSY.................................................................... III-20
3.5 REASSEMBLING PROCEDURE.............................................................................. III-26
[ 1 ] Reassembling the Mecha ASSY .................................................................... III-26
[ 2 ] Installing the Panel Cover............................................................................... III-33
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