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) circuit card supplies operating power to circuit cards accommodated 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 selected among 20Hz, 25Hz, 75Vrms, 90Vrms by switch setting on this card. In addition, a
Howler Tone circuit resides on this card.
Figure 2-18 Location 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)
-48 V (For LC, TRK)
DC-DC
RGU
HOW
SUB
PWR
REL
NFB
-48 V
+80V (Option)
Note
+80 V (For MWL)