Brother PT-2300 Service Manual page 65

CHAPTER III ELECTRONICS ........................................................................... III-1
3.1 OUTLINE OF CONTROL ELECTRONICS ............................................................ III-1
3.1.1 Configuration of the Electronic Part ................................................................ III-1
3.1.2 Main PCB....................................................................................................... III-1
3.1.3 Power Supply PCB ......................................................................................... III-1
3.1.4 Cassette Sensor ............................................................................................. III-1
3.1.5 DC Motors ...................................................................................................... III-1
3.1.6 Thermal Print Head ........................................................................................ III-1
3.2 MAIN PCB............................................................................................................. III-2
3.2.1 Block Diagram................................................................................................ III-2
3.2.2 CPU ............................................................................................................... III-3
3.2.3 ROM .............................................................................................................. III-3
3.2.4 Key Contacts Matrix and Solder Points........................................................... III-4
[ 1 ] Key contacts matrix ..................................................................................... III-4
[ 2 ] Solder points ............................................................................................... III-5
3.2.5 Power On/Off Circuit and Power Saving Circuit.............................................. III-6
[ 1 ] Power On/Off circuit .................................................................................... III-6
[ 2 ] Power saving circuit .................................................................................... III-7
3.2.6 DC Motor Driver Circuit .................................................................................. III-8
3.2.7 Cutter Motor Driver Circuit.............................................................................. III-10
3.2.8 Thermal Head Drive Circuit ............................................................................ III-11
3.2.9 Voltage Detector Circuit and Temperature Sensor Circuit............................... III-12
[ 1 ] Voltage detection circuit .............................................................................. III-12
[ 2 ] Ambient temperature sensor circuit ............................................................. III-12
3.2.10 Cassette Sensor Circuit .................................................................................. III-13
3.2.11 Cutter Sensor Circuit ...................................................................................... III-14
3.2.12 Oscillator Circuit............................................................................................. III-14
3.2.13 Reset Circuit................................................................................................... III-15
CONTENTS
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