Brother SC-2000 Service Manual page 110

CHAPTER III THEORY OF OPERATION.................................................................. III-1
1. MAIN PCB .................................................................................................................................. III-1
1.1 Logic Components......................................................................................................... III-1
1.2 EEPROM Circuit............................................................................................................ III-1
1.3 Thermal Head Drive Circuit............................................................................................ III-2
1.4 Thermal Head Power Supply Control Circuit .................................................................. III-3
1.5 Stepping Motor Drive Circuit (Main Motor) ..................................................................... III-4
1.6 Stepping Motor Drive Circuit (Paper Feed Motor)........................................................... III-5
1.7 Main Oscillating Circuit .................................................................................................. III-5
1.8 Sub Oscillating Circuit.................................................................................................... III-6
1.9 Reset Circuit.................................................................................................................. III-7
1.10 Serial Interface Circuit ................................................................................................... III-8
1.11 Parallel Interface Circuit................................................................................................. III-9
1.12 5V Power Supply Circuit (Stabilization Circuit) ............................................................. III-10
1.13 LCD Control Circuit...................................................................................................... III-10
1.14 Charge/Discharge Control Circuit................................................................................. III-11
1.15 Size Detection, Open Cover Detection, and Key Scanning Circuit................................ III-12
1.16 Room Temperature Detection Circuit ........................................................................... III-15
1.17 Xenon Unit Release Detection Circuit .......................................................................... III-15
1.18 Xenon Unit Detection Circuit ........................................................................................ III-16
1.19 Reflective Sensor Circuit.............................................................................................. III-17
1.20 Transparent Sensor Circuit .......................................................................................... III-18
2. POWER SUPPLY PCB CIRCUIT .............................................................................................. III-19
3. CONTROL PANEL PCB CIRCUIT............................................................................................. III-19
4. MAIN CAPACITOR CHARGE PCB CIRCUIT ............................................................................ III-21
5. SIZE DETECTION CIRCUIT ..................................................................................................... III-21
6. REFLECTIVE SENSOR ASSY CIRCUIT................................................................................... III-22
7. TRANSPARENT SENSOR ASSY CIRCUIT .............................................................................. III-22
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