®
MH88620BR
C.O. SLIC
Preliminary Information
Features
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900 ohm input impedance
Externally selectable network balances
Transformerless 2-4 wire conversion
Programmable constant resistance feed
Off-Hook and Dial pulse detection
High immunity to externally induced longitudinal
currents
Auto ring trip
On-hook transmission (ANI) capability
Minimum protection circuitry required
Compatible with requirements of TELEBRAS
DOC/FCC, CSA/UL, CCITT
Excellent power dissipation (SIL vertical
mounting)
MH88620BR
ISSUE 3
April 1995
Ordering Information
40 Pin SIL Package
0°C to 70°C
Description
The Mitel MH88620BR SLIC provides all of the
functions required to interface 2-wire off premise
subscriber loops to a serial TDM, PCM, switching
network of a modern PBX. The MH88620BR is
manufactured using thick film hybrid technology
which offers high voltage capability, reliability and
high density resulting in significant printed circuit
board area savings. A complete line card can be
implemented with very few external components.
Applications
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On/Off-Premise PBX Line Cards
Central Office Line Cards
V
Bat
LGND
LCA
V
DD
V
EE
AGND
RING
RF1
RF2
TIP
TF1
TF2
Auto Ring
Trip
Matched
Feed
Resistors
Driver
Circuitry
and
Speech
Circuit
Loop
Current
Set
Switch-Hook
Threshold Set
Ring
Filter
Switch-Hook
Detect
SHK
Impedance
Network
2W/4W
conversion
N1
N2
TRD
Test Relay
Driver
Ring Relay
Driver
Gain Adjust
TRC RGND VRLY RNGC RRD
Z1
Z2
GRX1 GRX0 RX GTX1 GTX0 TX
Figure 1 - Functional Block Diagram
2-145
MITEL [ MITEL NETWORKS CORPORATION ]
