Valleylab Force FX-C - Low Voltage Power Supply; RF Output Stage

Force FXTM-C Service Manual
Power Supply/RF Board
Low Voltage Power Supply
The low voltage power supply is rated for 40 watts. It delivers a regulated
+5 Vdc and ±12 Vdc ouq-nlt. This power supply automatically adjusts for
both input voltage ranges. It also has internal current limiting. The
pinouts between the low voltage power supply and the Power Supply /
RF board are listed below:
PIN Voltage Test Point
+5 Vdc
TP3
2
-12 Vdc
TP5
3
+ 12 Vdc
TP6
4 GROUND TP9
The low voltage power supply specifications are as follows:
Output Voltage Output Current
Output Power*
+5 Vdc 4000 mA 20.0 W
·-12Vdc
400 mA
4.8W
+
12 Vdc 2000 mA
24.0W
• Total output power cannot exceed 40 W
RF Output Stage
Warning
High frequency, high voltage signals that can cause severe burns are present in
the RF output stage and in the associated mounting and heat sink hardware
described in this
manual. Take appropriate precautions when testing and
troubleshooting this area of the
generator.
The RF stage consists of a single MOSFET power switch with associated
gate drive circuitry, an RP power transformer, tuning capacitors, an RF
output L-C-C filter, output directing relays, and topology selecting relays.
Also included in this section are the RP voltage and current sense circuits
and a switched damping netvvork for certain operational modes.
The MOSFET gets its gating signal from the T_ON ASIC on the Control
board. The T_ON ASIC also provides the gating signal for the switched
damping netvvork.
4-21