MH89625C Datasheet, PDF (1/16 Pages) Mitel Networks Corporation – OPS/DID PCM SLIC Preliminary Information

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
Applications
• Off premise digital PBX line cards
• DID (Direct Inward Dial) line cards
• PABX, Key Systems, Central Office Equipment
ISSUE 4
Ordering Information
May 1995
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.
VBat
LGND
LCA
GS
VREF CA
TIP
RING
RF2
RF1
Tip
Drive
Current
& Voltage
Sensing
Ring
Drive
Line
Supervision
Constant
Current &
Voltage
Control
Ring
Trip
Filter
Gain
Adjust
2w/4w
hybrid
Impedance
Matching
VX _VREF
CA
DSTo
DSTi
VR
CODEC ^CSTi
F1i
CS
SD0 SD1 SD2 SD3
Relay
Driver 1
Relay
Driver 2
Relay
Driver 3
Relay
Driver 4
LED
SHK
RD1
RD2
RD3
RD4
Figure 1 - Functional Block Diagram
DSTi
DSTo
CSTi
F1i
C2i
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