®
MH89625C
OPS/DID PCM SLIC
Preliminary Information
Features
•
Input impedance variants:
- 600Ω
- 200Ω + 680Ω // 0.1µF
- 200Ω + 560Ω // 0.1µF
Operates with a wide range of battery voltages
Constant current battery feed with constant
voltage fallback for long loop drive capabilities
Overvoltage and short circuit protection
Off-hook detection and LED indicator drive
Dial pulse detection
Ring trip filter with auto ring trip
Ring relay driver plus three more uncommitted
relay drivers
Transformerless 2W to 4W conversion
A/D and D/A conversion
Conforms to A-Law PCM
Analog and digital loopback
Conforms to CCITT k.20 overvoltage surge
requirements with external primary protection
circuitry
ISSUE 4
May 1995
Ordering Information
MH89625C
MH89625C- 5
MH89625C- 6
600Ω
200Ω + 680Ω // 0.1µF
200Ω + 560Ω // 0.1µF
•
•
•
•
•
•
•
•
•
•
•
•
40 Pin DIL Package
Description
The Mitel MH89625C SLIC (Subscriber Line
Interface Circuit) provides a complete interface
between an off-premise telephone line and a digital
switching system. All BORSCHT functions of Battery
Feed, Overvoltage Protection, Ringing Feed, Line
Supervision, Codec, 2-4 Wire Hybrid and Test are
provided requiring only a few external components.
The input impedance conforms with Chinese
standard requirements. The device is fabricated
using thick film hybrid technology which incorporates
various technologies for high voltage capability,
optimum circuit design and very high reliability.
Applications
•
•
•
Off premise digital PBX line cards
DID (Direct Inward Dial) line cards
PABX, Key Systems, Central Office Equipment
VBat
LGND
LCA
GS
VREF
CA
TIP
Tip
Drive
Gain
Adjust
VX
VREF
CA
DSTi
DSTo
DSTi
CSTi
DSTo
CSTi
F1i
C2i
VR
Current
& Voltage
Sensing
Constant
Current &
Voltage
Control
2w/4w
hybrid
CODEC
F1i
CS
SD0 SD1 SD2 SD3
Impedance
Matching
RING
RF2
RF1
Ring
Drive
Ring
Trip
Filter
Relay
Driver 1
Relay
Driver 2
Relay
Driver 3
Relay
Driver 4
Line
Supervision
LED
SHK
RD1
RD2
RD3
RD4
Figure 1 - Functional Block Diagram
2-269
MITEL [ MITEL NETWORKS CORPORATION ]
