IC 7100 controls the ACS module and the HOP module. The OSD output of 7100 displays the
Convergence Service mode. Sync on Pins 53 and 55 synchronize the OSD. The A bus communicates
with the Microprocessor on the SSB, the B bus communicates with the Memory IC,7000, and the
Convergence processor. The C bus communicates with the HOP module via the SSM.
7001 SSB Power Supply and Reset
Figure 44
The Microprocessor on the SSB is powered by a 3.3 volt supply. The 5 volt standby supply feeds the
3.3 volt regulator IC 7005. This circuit is protected by fuse 1003. When the set is turned On,
Transistor 7002 turns On. Transistor 7003 is delayed from turning On until Capacitor 2017 is charged.
This delay allows 7004 to stay turned Off long enough for the Reset line to High via resistor 3017.
When 2017 is charged, 7003 turns On, turning 7004 On. The Reset line then goes Low and stays
Low.