dell p780 D99 chassis-troubleshooting manual.pdf | | D99 CHASSIS
OPERATION MANUAL TROUBLESHOOTING MANUAL
TABLE OF CONTENTS
CIRCUIT DESCRIPTION D Board (Power Supply Section) ... 2 D Board (Deflection Section) ... 9 A Board ... 20 GENERAL TROUBLESHOOTING ... 26 PARTS LEVEL BOARD REPAIR ... 37
TRINITRON® COLOR COMPUTER DISPLAY
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CIRCUIT DESCRIPTION D BOARD POWER SUPPLY SECTION Power Supply Electrical Circuit
The power supply is located on the D Board. It has three modes of operation that are controlled by a microprocessor. The topology is a discontinuous mode flyback converter with photocoupler feedback for regulating the secondary voltages. Circuit operation and troubleshooting are explained in the following sections:
Operation Modes AC Input Degauss Circuit Primary Circuitry Operation Modes
Secondary Circuitry Protection Circuits Troubleshooting
The power supply has four modes of operation, `off', `active off', `suspend/standby' and ` |