Power Supply Board Section, Input Circuit | Panasonic KX-FT21RS

KX-FT21RS

6.12. POWER SUPPLY BOARD SECTION

This power supply board uses the switching regulator method.

[Input Circuit]

The input current goes into the input rectifier circuit through the filter circuit. The filter circuit decreases the noise voltage and the noise electric field strength.

[Rectifier Circuit]

The input current is rectified by D101,D102,D103 and D104 and charges C106 to make DC voltage. Then it supplies power to the converter circuit.

[Kick-on voltage circuit]

Bias is applied to the Q101 gate via this circuit when the AC power is turned on and Q101 begins operating.

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Panasonic KX-FT21RS Power Supply Board Section, This power supply board uses the switching regulator method, Input Circuit

Contents

KX-FT21RS Contents For Service Technicians Safety PrecautionsBattery Caution Insulation Resistance Test AC Caution Live Electrical Sections Personal Safety PrecautionsMoving Sections of the Unit General FeaturesFacsimile Integrated telephone system Optional Accessories Specifications Ccitt No Test Chart Control Panel Location of ControlsOverview Connections Document Stacker InstallationInstalling the Recording Paper # , then Setting Your LogoExample Bill Press START/COPY/SET Documents you can send To select characters with the dial keypad Outline Maintenance Items and Component LocationsMaintenance Check ITEMS/COMPONENT Locations Maintenance List Maintenance Cycle Disconnect the power cord and the telephone Maintenance Cleaning the Document Feeder UnitClean the document feeder rollers, sub roller Line cord Refer to 4 Disassembly Instruction Cleaning the Thermal HeadCleaning the Pick UP Roller Precautions Troubleshooting SummaryTroubleshooting User Recoverable Errors Document Jam Starting Troubleshooting Troubleshooting Details Simple Check List Troubleshooting Items Table No document feed ADF Auto Document Feed Section Paper JAM Multiple feed Skew Image is distorted When printing Black or white vertical lines appear Skewed receiving image KX-FT21RS KX-FT21RS Facsimile section Communication Section Defective facsimile section Transmit problem Sometimes there is a transmit problem Check Document Paper JAM Reception problem Unit can copy, but cannot transmit/receive Cause and Countermeasure Erroneous detection due to an echo or echo cancelerEcho/Echo Canceler Countermeasure a Causes and Countermeasures Cause aCause B Countermeasure B Reception Operation Transmission Operation How to output the Journal Report TX=TRANSMISSION RX=RECEPTION Countermeasure KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS Hint Remote programming KX-FT21RS YES/NO Program Mode Table 996 Journal Digital Board Section Please refer to the 2.3.4.3.1. Digital Block Diagram Digital Block Diagram KX-FT21RS Normal Wave Patterns Pin No. Diagram KX-FT21RS KX-FT21RS NG Example Check the Status of the Digital Board Analog Board Section Defective ITS Integrated Telephone System Section Key components for troubleshooting Power Supply Board Section Troubleshooting Flow Chart KX-FT21RS Broken parts repair details D101, D102, D103, D104 No key operation No LCD indication Operation Board Section Check the read position PS2 Sensor SectionCheck the document sensor PS1 Refer to 6.4.4. Scanning Block Read Section KX-FT21RS Refer to 6.4.3. Thermal Head Thermal Head Section Operation Flow Programming and ListsOperation Above values are the default values 3ALL Service Function Table See 2.6.1. Printout Example Service Mode Settings Example of a printed out list Other Test Functions Print Test Pattern Dtmf Signal Tone Transmit SelectionButton Code Table Compression Code MH/MR DescriptionsMslt means Minimum Scan Line Time. Used only at the factory EQM Printout Example Adjusting the Feed Pressure Adjustments Disassembly Instructions KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS KX-FT21RS Preparation Flat Package IC Removal Procedure KX-FT21RS Connection Diagram Codec IC5 D/A converter General Block Diagram 256k AC220V+24V +5V 100 Block DiagramControl Section Decodes the address Asic IC1Execute modulation and demodulation for the FAX Transmits the recorded data to the thermal head 102 103 Vddc 104 RAM IC3 Reset CircuitROM IC2 Circuit Operation Sram and RTC Back UP CircuitFunction Supervision Circuit for the Thermal Head Temperature LED Arraycis Image Data Flow During Facsimile Operation Facsimile SectionCopy Fine, Super-Fine, Half Tone Transmission Analog Block DiagramFront/End Head 110 Thermal Head 112 Scanning Block Stepping Motor Drive Circuit Stepping Motor Phase Pattern Gear Section Mode Selection Transmit mode Mode OperationReceive mode Copy mode 117 See 6.5. Sensers and SwitchesScanning Printing 118 Copying 119 Sensors and SwitchesAll of the sensor and switches are shown below 120 Motor Position SensorRecording Paper Sensor SW201 121 Read Position Sensor PS2Document Sensor PS1 Function Modem SectionOn ITU-T International Telecommunications´ Union Definition of Each Group Control time Concerning Transmission TimeImage transmission time Hold time DIS/DTC DCS 124 125 CFR 126 This unit uses one-dimensional MH format 127 Redundancy Compression Process Coding Mode Modem Circuit Operation Analog Unit General NCU SectionLine Relay RLY1 Bell Detection Circuit Line Amplifier and Side Tone Circuits Handset Circuit Monitor Circuit EXT. TEL Circuit Diagram Operation Panel Analog Switch IC1 ControlKEY Scan Key Matrix LCD Control Sensor Detection This power supply board uses the switching regulator method Power Supply Board SectionInput Circuit Rectifier Circuit KX-FT21RS Control Circuit and Detecting Circuit Surge Absorber CircuitOver Current Limiter O.C.L Over Voltage Circuit For the Schematic Diagrams 141 Printed Circuit Board 142 TP8 TP7 C26 SW201 D104 D103C230 C231 C106 C225 IC101 L203R215 Q203 145 F101 146 Printed Circuit Board Operation Board 147 Schematic Diagram 148 Schematic Diagram Analog Circuit 149 Schematic Diagram Switching Power Supply 150 Schematic Diagram Operation Circuit 151 152 153 Operation Panel Section 154 Upper Cabinet Section 155 Lower CABINET/P.C.B. Section Motor Section 157 Actual Size of Screws and Washer 158 159 This replacement parts list is for KX-FT21RS onlyCabinet and Electrical Parts 160 Digital Board Parts 161 162 Analog Board Parts 163 164 Operation Board Parts 165 Power Supply Board Parts Fixtures and Tools