Circuit Power - Avaya Nortel Communication Server 1000 Reference

Microcontroller
The analog message waiting line card contains a microcontroller that controls the internal
operation of the card and the serial card LAN link to the controller card. The microcontroller
controls the following:
• reporting to the CE CP through the card LAN link:
- card identification (card type, vintage, and serial number)
- firmware version
- self-test status
- programmed configuration status
• receipt and implementation of card configuration:
- programming of the codecs
- enabling/disabling of individual units or entire card
- programming of input/output interface control circuits for administration of line
interface unit operation
- enabling/disabling of an interrupted dial tone to indicate call waiting
- maintenance diagnostics
- transmission loss levels
Signaling and control
The signaling and control portion of the card provides circuits that establish, supervise, and
take down call connections. These circuits work with the system CP to operate the line interface
circuits during calls. The circuits receive outgoing call signaling messages from the CP and
return incoming call status information over the DS-30X network loop.

Circuit power

The +8.5 V DC input is regulated down to +5 V DC for use by the digital logic circuits. All other
power to the card is used by the line interface circuits. The +15.0 V DC input is regulated down
to +12 V DC to power the analog circuits. The –48.0 V DC input is for the telephone battery.
Ringing power for telephones is 86 Vrms ac at 20 Hz on –48 V DC. The Rsync signal is used
to switch 20 Hz ringing on and off at the zero current cross-over point to lengthen the life of
the switching circuits.
Circuit Card Reference
Functional description
July 2011 369