Information subject to change
97-2105006_4-2-15
2105 OPERATOR’S MANUAL –
SECTION 7
36
7
Amplifier Signal Flow
7.1 Input Signals
The input signal is routed from the SIM (Specialized
Input Module) on the back panel to the Main board.
From there, the signal is amplified through low-noise
operational amplifier gain stages, compensation
networks, and current limiting/ODEP and then final
gain stage to the Output board. At the Output board,
the signal is sent through pre-drivers, output stage
drivers, then to the Output stage whose topology is
a full-complimentary, full-bridge, AB+B mode transis
-
tor design. Amplifier control and status is handled by
logic circuits tied to the Display/Control board on the
front panel. Protection is provided by current limiting
circuits and special junction temperature simulation
circuits using thermal feedback from the main heat
sinks on the Output board.
Figure 7.1 – Board-Level Functional Block Diagram
7.2 AC Mains Power
Power to the amplifier is connected through a 20-
amp IEC-type inlet connector with an integral EMI
filter network on the back panel. AC mains power is
first routed through the front panel switch/breaker,
then to the Power Supply board. From there, the AC
mains are distributed to the main power transform-
ers, and then from the transformers back through the
Power Supply board to the Main board.
The Power Supply board allows for easy configura
-
tion of primary and secondary voltages. The Power
Supply board also performs the “bi-level” function.
This allows the power supply rails to the Output sec-
tion to increase or decrease depending on demand
and keeps the voltage dropped across the outputs to
a minimum, thereby decreasing heat dissipation.
