AT&T 3B2/300 Technical Reference Manual page 409

FUNCTIONAL D E S C R I P T I O N - - - - - - - - - - - - - - - - - - - - - - - - - -
CM 194B Backplane
The CM194B is a 12-slot backplane board. The backplane board plugs into the 100-pin (A or J02)
and 60-pin (B or J03) input/output expansion connectors on the system board. A maximum of either
6 double-width or 12 single-width feature cards can be plugged into this backplane.
All bus signals for the features cards are from the J02 and J03 system board connections. Certain
bus signals are terminated on the backplane as shown on Figure 3-49. No connections are provided for
the Card Select 15-13 (CS15-13[0]) signals by the CM194B Backplane.
Power and ground for the features cards are handled differently from the CMl 93A/B Backplane.
Because of the number of feature cards supported by the CMl 94B Backplane, +5 volt (VCC), + 12 volt
(V12P) and ground connections are directly supplied from the Power Supply via the 12-pin power
connector on the backplane. Only the -12 volt (V12N) power is supplied to the backplane from the
system board connector (J02).
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