Power Supply - Philips L05HD Training Manual

Power Supply Block (Figure 1)
The Power supplies are both located on the Family board. The supplies are divided into two
sections, the Auxiliary and Main section. A single filter and rectifier circuit supplies both
sections. The Auxiliary supply operates in a low power mode when the load is reduced. In
the standby mode, the 3.3 and 6 volt supplies are operating. The 3.3 volt supply provides
power to the processor section of the Hercules. The 6 volt supply provides power to the IR
receiver. The Main supply is switched Off via the Standby line.
When the set is turned On, the "B" line from the Hercules processor goes High switching
7547 which turns 7535, 7509, and 7545 On. The +3V3A, +6VA, +12VA, and +8VA supplies
are then switched On. The load placed on the Aux Power supply will cause it to switch to the
full power mode. At the same time, the STBY line switches Low turning the Main SMPS
supply On. The supply produces a +6 volt, +140 volt, -16 volt, and +16 volt supplies.
The +Vaudio (+16 volt) supply switches on the degauss relay.
FIGURE 1 - POWER SUPPLY BLOCK
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