Philips FL9.1, Техническое учебное пособие

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Board Level Repair (Figure 2)
The Fl9.1 chassis is designed for board level repair.
Standby mode
In Standby, the processor on the Digital Main board is powered by the AL+3.3V supply. This
voltage can be measured on pins 21 and 22 of connector CN301 on the power supply board.
Power On
When the set is turned On by the keyboard or the remote, the processor on the Digital Main
board switches the P-ON-H1 and P-ON-H2 lines High. This switches the power supply to the
full power mode.
Protect
If any of the supplies fail or the Inverter board is not functioning the Protect lines will cause
the set to shut down. In normal operation the Protect lines should read as follows:
Protect 1 2.4V
Protect 2 0.0V
Protect 3 3.3V
Since a failure in the Protect lines will cause an immediate shutdown, the power supply
should be forced On to check for missing supplies.
1. First unplug CN301 and CN302 to disconnect the Digital Main board.
2. Jumper the AL3.3V supply to P-ON-H1 and P-ON-H2.
P-ON-H1 and P-ON-H2 test points AL3.3V test point (top center)
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