Sony STR-VX4 - Page 36

SONY STR-VX Series Circuit Operation
Power Supply (all models)
The STR-VX1, -VX2 and -VX4 employ
conventional power supplies. The
STR-VX5 and -VX6 employ pulse power
supplies. The configuration of the
pulse power supply is identical to that
of previous models, and will not be
discussed here.
STR-VX3, -VX4, -VX5 and
-VX6 Protection Circuit
Table 2 summarizes the protection
circuit employed in each model. The
protection circuits used in the
STR-VX6 will be discussed here.
Table 2.
circuit |circuit
breaker|breaker
relay relay | relay | relay
(1.9A) |(1.9A)
[Some tier epee [ee
[ne vatage ouside | ee [see [ve [oe fe
a
ce
Pie Ds
pa fs
Speaker Protection
Input Muting
Primary Fuse or Circuit Breaker
In-Rush Current Relay
Speaker Protection Relay Drive and Input Muting
A relay is employed to protect both the
speakers and the amplifier itself. The
following events take place when the
power switch is turned on or turned
off. Refer to Figure 11.
1. Immediately after power switch is
turned on
Q723 Q726
Q722 OFF 7725 OFF—+Q719 ON-—>input muting ON
Lite cee ee ee Fe —»speaker protection relay OFF
10