MH88612K Datasheet, PDF (1/8 Pages) Mitel Networks Corporation – Subscriber Line Interface Circuit Preliminary Information

MH88612K
®
Subscriber Line Interface Circuit
Preliminary Information
Features
• Input impedance 600 Ω
• Transformerless 2-wire to 4-wire conversion
• Battery and ringing feed to line
• Off-hook and dial pulse detection
• Ring ground over-current protection
• Adjustable constant current feed
• Relay drive output with diode protection
• Power Denial
• Wide V_BAT Operating Range
• Tip/Ring Reversal
Applications
Line interface for:
• PABX
• Intercoms
• Key Telephone Systems
• Control Systems
ISSUE 3
April 1995
Ordering Information
MH88612K 30 Pin SIL Package
0°C to 70°C
Description
The SLIC provides a complete interface between a
switching system and subscriber loop. Functions
provided include battery feed, ringing feed and tip-
ring reversal to the subscriber line, 2-Wire to 4-Wire
hybrid interfacing, constant current feed and dial
pulse detection. The device is fabricated as a thick
film hybrid using various technologies.
RF
TF
TIP
RING
RC2
VRLY
RD1
RC1
LPGND
VBat PD
VDD VEE ^GNDA
T/R
Reverse
T/R Reverse
Relay Driver
Relay
Drive
Circuit
Battery
Feed
Power
Denial
Over Current
Protection
Constant
Current
Feed
2-Wire to
4-Wire
Conversion
Loop
Supervision
RV
SHK
Figure 1 - Functional Block Diagram
VR
VX
VRef
CAP
2-121