Related Manuals for Panasonic GP 31
Summary of Contents for Panasonic GP 31
- Page 1 Technical Guide Colour Television GP 31 Chassis Circuit Explanations Panasonic Panasonic AVC Networks Kuala Lumpur Malaysia Sdn. Bhd.
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Page 2: Table Of Contents
Contents Introduction Location of Control & Circuit Boards GP-31 Chassis Block Diagram 1. Tuning Circuit 1.1 Signal Processing 1.2 IF Control 2. Ultimate One Chip IC601 2.1 Features 2.2 IIC Bus 2.3 Memory IC 2.4 Reset Circuit 2.5 IC601 Pin Configuration 3. -
Page 3: Introduction
This Technical Guide contains information for GP 31 chassis and should be used in conjunction with the relevant Service Manuals for this chassis. As the Technical Guide for the GP 31 chassis covers such a wide range of models, some differences may occur in circuit descriptions and component references. -
Page 4: Location Of Control & Circuit Boards
Location of Control & Circuit Boards L-Board A- Board Board Name Function A-Board Main Board L-Board CRT Board... -
Page 5: Gp-31 Chassis Block Diagram
GP-31 Chassis Block Diagram... -
Page 6: Tuning Circuit
Tuning Circuit Outline Fig 1.0 The tuner is designed for reception of the conventional frequencies to date and the intermediate special channel frequencies. The IF stage of the tuner contains the video and audio demodulators which are designed for most widely used TV standards. Signal Processing 1. - Page 7 UOC IC601...
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Page 8: Ultimate One Chip Ic601
Ultimate One Chip IC601 Outline The IC601 TDA959xN, also known as UOC, is a high-quality single chip TV processors IC which allow the economic integration of features in all classes of single- scan TV sets. UOC combine the functions of a video processor together with a microcontroller and teletext decoder. -
Page 9: Iic Bus
I²C bus Fig 2.0 • The I²C bus is a two bus system consisting of a data line and a clock line. • 5V is set for SDA / SCL. [Fig 2.0] • Allow a large number of switching and control functions of GP-31 chassis. The UOC IC601 generates bus signals which control the following hardware configuration. -
Page 10: Reset Circuit
The memory IC1103 receives the data listed below as supplied from the UOC IC601 through I²C bus [Fig 2.1]. It is input or output whenever it is necessary. This memory IC is a non-volatile type, which data is maintained permanently although the power is cut off. -
Page 11: Ic601 Pin Configuration
IC601 Pin Configuration Pin No. Name Function KEYSCAN Panel key AUTO/MAN Geomagnetic controlling H: Auto L: Manual MSP RESET H: Normal L: Reset (During power ON) GND (D) Digital ground for µ-Controller core and periphery AV/TV TV / AV search H: AV / Auto Search L: TV 4.5V / OTHERS... - Page 12 Ground for TV-processor AV1V Video AV1 input Ground for TV-processor AV2V Video AV2 input Chroma input WHSTR White stretch capacitor CVBSO CVBS output AUDOUT / AMOUT Audio output / AM audio output (volume controlled) Not used INSSW2 RGB / YUV insertion input V (R-Y) input / P input Y input...
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Page 13: Video Circuit
Video Circuit... -
Page 14: Video Signal Processing
Video Circuit Outline Video signal processing is performed in the UOC IC601. The IF signal from tuner, video inputs from AV1, AV2 and YUV are fed to UOC IC601 for video processing. RGB output from UOC IC601 is then fed to CRT drive circuit to drive the CRT. Video Signal Processing Fig 3.0 IF signals from tuner are input to IC601 at pin 18 &... -
Page 15: Audio Circuit
Audio Circuit Stereo / AV Stereo... - Page 16 Mono...
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Page 17: Audio Processor
Audio Circuit Outline Three sound modulations available in GP-31 chassis which are STEREO, AV STEREO and MONO. Depending upon the version of the UOC IC601 and MSP IC2101 used, gives different sound modulation. Audio Processor Two different sound processors are used in GP-31. IC2101 is used as Sound Processor and IC2301 as Audio Amplifier. -
Page 18: Deflection Circuit
Deflection Circuit... - Page 19 Horizontal Output Circuit...
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Page 20: Horizontal Output Circuit
Horizontal Output Circuit Outline 1. The horizontal synchronous pulse output from IC601 pin 30 is then input to the Horizontal Drive Circuit (Q501, T553). 2. The horizontal drive circuit creates a base current (drive current) fully sufficient to turn the horizontal output circuit (Q551) ON and OFF quickly, and inputs this current to the horizontal output circuit (Q551). -
Page 21: Horizontal Output Operation
Horizontal Output Operation 1. Tr (Q551) base input does not work until it exceeds a certain level [Fig 5.0]. 2. A positive polarized pulse is added to the base and as the base voltage exceeds a certain level, Tr turns ON. Then the collector current increases and the current flows into the deflection coil (t1- t2). - Page 22 Vertical Output Circuit PROTECTION...
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Page 23: Vertical Output Circuit
Vertical Output Circuit Outline 1. The main function of this circuit is to produce a sawtooth deflection current and amplify the vertical sawtooth waveform to the vertical deflection coil for vertical scanning. 2. IC451 is a vertical IC that provides output deflection current to the vertical coil of the deflection yoke. -
Page 24: Colour Output
Colour Output Outline In order to avoid damage caused by long cathode lines and thereby trim the frequency response, the RGB output stage is mounted on the CRT board. The RGB signals fed to the colour output stage are fed from IC601 (located on the A-Board) from pins 56 (R), 57 (G), 58 (B). -
Page 25: Protection Circuit
Protection Circuit Outline 1. The main function of the protection circuit is to prevent main chassis of TV set from serious damage when faults occur in the circuit. 2. The protection input (Pin 34 of IC601) is intended for overvoltage (X-ray) protection, +B 140V overcurrent protection and vertical drive protection. - Page 26 Operation • Power Supply Protection Condition 1: power supply interruption during power ON If the power supply is interrupted, pin 34 of IC601 pulled HIGH, then TV set will go to standby (protection mode) and LED starts blinking. Condition 2: circuit malfunction when TV set is already ON If TV set is under ON condition and circuit malfunction happened, pin 34 of IC601 pulled HIGH, then TV set will go to standby (protection mode) and LED starts blinking.
- Page 27 GP31 Power Map...
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Page 28: Power Circuit
Power Circuit... -
Page 29: Start-Up Circuit
Power Circuit Outline The supply voltage for the main power supply circuit is fed to the bridge rectifier D803 where the AC voltage is fully rectified and smoothed by C810. [Fig 8.0]. This smoothed DC voltage then feeds the supply to the drain terminal of IC801 pin 1 via the winding P1–P2 of transformer T801. -
Page 30: Regulation
signal. When this condition is detected, the internal MOSFET transistor is switched OFF. 4. When the internal MOSFET transistor of IC801 is switched OFF, the current flow via the primary winding P1, P2 stops. Energy stored in the primary winding is transferred to the secondary windings. -
Page 31: Over Current Protection Circuit
Over Current Protection Circuit 1. This circuit is performed by detecting the peak drain current of the internal MOSFET transistor of IC801, which is used to reverse the output of the internal oscillator of IC801. 2. The MOSFET drain current is detected by inputting the voltage drop developed across R820, R821 into pin 7 of IC801 via R830.