CHAPTER 2 NDA-24296
Page 112
Revision 1.0
PH-PW14
Power Switch

PH-PW14

Power S witch

1. General Function
This c ircuit card is a powe r supply card that supplies DC -48 V ope rati ng po wer t o the circuit cards mounted
in the TSWM. It also provides the DC-DC converter function which generates output power DC +5 V, -5
V, and +12 V to MISC slots.
The two PWR SWs cards make the power supply redundant.
Figure 2-49 -48 V Output Circuit Diagram
Con-
troller Con-
troller
DC-
DC DC-
DC
Load
Load
-48V
-48V IN
Switch
FUSE FUSE
PWR SW #0
FET Switch PWR SW #1