CHAPTER 2 NDA-24296
Page 56
Revision 1.0
PA-PW54-B
Dual Power

PA-PW54-B

Dual Power

1. General Function
The PA-PW54-B (DPWR) circui t card suppl ies operatin g power to circuit cards accommodate d in the PIM.
The -48V input power source, which is converted to +5V, -5V, and +12V, is distributed to each circuit card
in the PIM. This card is also equipped with a Ringing Generator Unit (RGU), whose output frequency and
voltage can be sele cted a mon g 20Hz , 25Hz, 75Vr ms, 90Vr ms by s wi t ch sett ing o n t his card. In add it ion, a
Howler Tone circuit resides on this card.
Figure 2-18 L ocation of PA-PW54-B (DPWR) Card within the System
Note: The +80V input is required for activating Message Waiting Lamps (MWLs) .
HOW (For LC)
CR (For LC)
+5V, +12V, -5V
DC-DC
RGU
HOW
SUB
PWR
REL
NFB
PA-PW55-B (PWR) PA-PW54-B (DPWR)
-4 8 V (For LC, TRK )
DC-DC
RGU
HOW
SUB
PWR
REL
NFB
-48 V
+80V (Option) Note
+80 V (For MWL)