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3-2
DC Power Distribution:
DC Regulation and Distribution
The following regulators are used:
The 5 V source from U505 is applied to:
• RX back end circuitry
• RX/TX audio filters
• 1/2 VCC generator
• VCO power source (Q705, Q706)
• RX B+ (Q304)
• TXVB (Q407)
• VCTCXO
The 5 V source is also applied to transistor switches Q304 and Q407. Q304 is turned on by Q305
when RX_EN (from U101 Pin 71) is high, and supplies the source to mixer, IF IC and LNA. Q407 is
turned on by Q408 when TX_EN2 (from U101 Pin 85) is high, and supplies the "TXVB" source to the
first transmitter stage Q401 base, Q402 gate, APC power source (U401 Pin 8) and ANT switch
(CR401).
The 3.3 V regulated source from U506 is applied to:
• MCU IC U101
• EEProm IC U104
• DTMF IC U103
• Audio processor IC U102
• Microphone bias circuitry
• And applied to Key PCB (LCD driver power source)
The 10 V source from U507 is applied to Charge Pump.
Table 3-1. Voltage Regulators
Reference No.
Description
Type
U505
5V regulator
TK11250
U506
3.3V regulator
TK11233
U507
Voltage Doubler (10V)
TC12140
Summary of Contents for P100 Series
Page 1: ...P100 Series Portable Radios Detailed Service Manual ...
Page 2: ......
Page 8: ...iv Notes ...
Page 18: ...xiv List of Tables Notes ...
Page 22: ...xviii Summary of Printed Circuit Boards and Bands Available Notes ...
Page 30: ...Notes 2 4 Test Equipment Service Aids and Service Tools Service Aids ...
Page 54: ...7 4 UHF2 Schematic Diagrams Overlays and Parts Lists Speaker and Microphone Schematic Notes ...
Page 128: ...7 78 Circuit Board Schematic Diagram and Parts List UHF2 435 480 MHz Notes ...
Page 150: ...7 100 Circuit Board Schematic Diagram and Parts List UHF2 MDC QCII R TTE 435 470 MHz Notes ...
Page 166: ...10 4 VHF Schematic Diagrams Overlays and Parts Lists Speaker and Microphone Schematic Notes ...
Page 192: ...10 26 Circuit Board Schematic Diagram and Parts List VHF 136 174 MHz Notes ...
Page 218: ...10 52 Circuit Board Schematic Diagram and Parts List VHF 136 174 MHz Notes ...
Page 242: ...10 76 Circuit Board Schematic Diagram and Parts List VHF MDC QCII R TTE 136 174 MHz Notes ...
Page 258: ...13 4 UHF1 Schematic Diagrams Overlays and Parts Lists Speaker and Microphone Schematic Notes ...
Page 328: ...13 74 Circuit Board Schematic Diagram and Parts List UHF1 MDC QCII R TTE 403 447 MHz Notes ...
Page 332: ...A 4 Warranty Service Support and Replacement Parts Further Assistance From Motorola Notes ...
Page 335: ......