MH88630 Datasheet, PDF (1/10 Pages) Mitel Networks Corporation – Central Office Interface (LS/GS) Preliminary Information

MH88630
®
Central Office Interface (LS/GS)
Preliminary Information
Features
• Transformerless 2-4 Wire conversion
• Line state detection outputs:
- forward current
- reverse current
- ring ground
- tip ground
- ringing voltage
• Programmable audio transmit and receive gain
• Loop start or ground start termination
• Selectable 600Ω or AT&T compromise balance
network
Applications
• PBX Interface to Central Office
• Channel bank
• Intercom
• Key system
ISSUE 7
Ordering Information
April 1995
MH88630
40-Pin DIL Package
0°C to 70°C
Description
The Mitel MH88630 Central Office Trunk Interface
circuit provides a complete audio and signalling link
between an audio switching equipment and a central
office. The loop seize circuitry is controlled by an
external input to provide either a loop start or ground
start termination. The device is fabricated using thick
film hybrid technology to achieve high density circuit
design.
RG FC RV RC TG
LPGND RINGND
VCC+ VCC- AGND
T
R
VTR+
VTR-
RXIN-
RXIN+
Signal Detection
Circuitry
Active
Termination
Ring
Ground
Network
Balance
Relay
Driver 1
Relay
Driver 2
Audio Section
Circuitry
(2 - 4 Wire)
QB QE XA XB XC
VDD VEE
RXOUT TXIN+ TXIN-
Figure 1 - Functional Block Diagram
RC1
RD1
RGND
CD
RD2
RC2
NETBAL
GSX
VX
VR
GSR
2-215