Datasheet MH88620IN Datasheet (MITEL)



MH88620IN

C.O. SLIC

Preliminary Information

Features

• 600 ohm inp ut imp eda nce

• Externally s electa ble net work ba lanc es

• Transformerless 2-4 wire conversion

• Programmab le c onsta nt resis tan ce feed

• Off-hook and dial pulse detection

• High immunity to externally induced longitudinal
currents

• Auto ring trip

• On-hook tran smissi on (A NI) cap ability

• Minimum p rotecti on circ uitry requi red

• Compatible with requ irem ents of CDOT D OC/
FCC, CSA/UL,CCITT

• Excellent power dissipation (SIL vertical
mountin g)

Applications

• On/Off-Premise PBX Line Cards

• Central Offic e Line C ard s

ISSUE 3 April 1995

Ordering Information

MH88620IN 40 Pin SIL Package

0°C to 70°C

Descript io n

The Mitel MH88620IN 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 MH88620IN 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.

VEE

AGND

2W/4W

conversion

GTX0

GTX1

Ring

Filter

SHK

N1
N2

TX

RING

RF1
RF2

TIP
TF1
TF2

TRD

LGND

VBat VDD

Matched

Feed

Resistors

Test Relay

Driver

TRC

Auto Ring

Trip

RGND

VRLY

Driver

Circuitry

and

Speech

Circuit

Ring Relay

Driver

RNGC

RRD

LCA

Loop

Current

Set

Impedance

Z1

Network

Switch-Hook

Detect

GRX0

GRX1Z2

Switch-Hook

Threshold Set

Gain Adjust

RX

Figure 3 - Functional Block Diagram

2-159

MH88620IN Preliminary Information

TIP

RING

TF1

TF2
RF1
RF2

LGND

LCA

VBAT

NC

RGND

VRLY

RRD

RNGC

NC
TRD
TRC

AGND

NC

N1

1
2
3
4
5
6
7
8

9
10
11
12
13
14
15
16
17
18
19
20

N2
NC

Z1
Z2

TX

RX
GTX0
GTX1

GRX0
GRX1

NC

NC

NC

SHK

IC
IC
IC

IC
VEE
VDD

Figure 2 - Pin Connections

Pin Description

Pin # Name Description

1TIPTip Lead. Connects to the TIP lead of the subscriber line
2RINGRing Lead: Connects to the Ring lead of the subscriber line.

21
22
23
24

25
26
27
28

29
30
31
32
33
34
35
36
37
38
39

40

3TF1Tip Fee d 1: Access point for balanced ringing. Normally connects to TF2.
4TF2Tip Feed 2: Access point for balanced ringing. Normally connects to TF1.
5RF1Ring Feed 1: Access point for balanced ringing. Normally connects to RF2.
6RF2Ring Feed 2: Access point for balanced ringing. Normally connects to RF1.
7LGNDBattery Ground. V

return path. Connected to system’s energy dumping ground.

BAT

8LCACurrent Limit Se t (Inpu t) : The current limit is set by connecting an external resistor as

shown in Table 5. For 70mA default current, this pin is tied to -5V.

9V

Battery Voltage: Typically -48V dc is applied to this pin.

Bat

10 RS1 Ring Sense Resistor Conn ectio n 1. See Figure 7a.
11 RGND Ring Driver Ground Con nection .
12 VRLY Relay Supply Voltage Connection

13 RRD

Ring Relay Drive (Output). Connects to ring relay coil

14 RNGC Ring Relay Control (Input)
15 RS2 Ring Sense Resistor Conn ectio n 2. See Figure 7a
16 TRD Test Relay Drive (Output): Connects to test relay coil.

17 TR C
18 AGND Analog Ground: V

Test Relay Con trol (Input).

and V

DD

return path

EE

.

19 NC No Connection: Reserved.
20 N1 Network Balan ce Nod e 1. An external network balance impedance can be connected

between N1 and AGND. See Fig 4. for compl ex imped ances. N2 no connecti on.

21 N2 Network Balance Node 2. See Fig 4. N2 connects to GND for 600Ω balance. N1 no

connection.

2-160

Preliminary Information MH88620IN

Pin Description (Continued)

Pin # Name Description

22 NC No Connection. Reserved
23 Z1 Line imp eda nce Nod e 1. Normally connect s to Z2. See Fig. 3.
24 Z2 Line impedance Nod e 2. Normally connect s to Z1. See Fig 3.
25 TX Transmit (Output)
26 RX Receive (Input). 4-wire (AGND) referenced audio inpu t.
27 GTX0 Transmit Gain Node 0. Connects to GTX 1 for 0dB transmit gain.
28 GTX1 Transmit Gain Node 1. Connects to a resistor to AGND for transmit gain adjustment.

29 GRX0 Recei ve Gai n Nod e 0. Connects to GRX1 for 0dB gain

30 GRX1 Receive Gain Node 1. Connect to a resistor to AGND for receive gain adjustment
31 NC No Connection. Reserved
32 NC No Connection. Reserved.
33 NC No Connection. Reserved.

34 SHK

35.38 IC Internal Con necti on.
39 VEE Negative Supply Voltage. -5V dc.
40 VDD Positive Supply voltage. +5V dc

Off-Hook Indication (Outp ut). A logic low output indicates when the sub scriber
equipment has gone Off-Hook.

. 4-wire (AGND) referenced audio output .

2-161

MH88620IN Preliminary Information

Absolute Maximum Ratings * All voltages are with respect to GNDA unless otherwise stated.

Parameter Symbol Min Max Units

1 Supply Voltages LGND -V

V

GND - V

2 Storage Temperature T

* Exceeding these values may cause permanent damage. Functional operation under these conditions is not implied.

DD -

Bat

GND

EE

S

-40 +125 °C

65

6
6

Recommended Operating Conditions† - Voltages are with respect to GNDA unless otherwise stated.

Characteristics Sym Min Typ* Max Units Comments

1 Operating Temperature T
2 Supply Voltages V

* Typical figures are at 25°C and are for desi gn aid only; not guarantee d and not subje ct to producti on testing.
† Voltages specified are with respect to LGND.

V
V

OP

Bat*

DD

EE

070°C

-44

4.75

-4.75

-48

+5.0

-5.0

-60

5.25

-5.25

V
V
V

DC Electrical Characteristics*

‡

Characteristics Sym Min Typ

1

Operating Loop Current

I

Loop

17
16

Max Units Test Comments

70 mA

mA
mA

= 0Ω, LCA = -5V

R

Loop

1500Ω
2000Ω V

Bat

V
V
V

= -48V

Variation in Loop current
from nominal

2

Operating Current

Power Dissipation

SHK

3

Low Level Output Voltage
High Level Output Voltage

4

RNGC

TRC

5

Low Level Input Voltage
High Level Input Voltage

Low Level Input Current
High Level Input Current

* DC Electrical Characteristics are over recommended operating conditions unless otherwise stated.
‡ Typical figures are at 25°C with nom inal ±5 V supplie s and are for desig n aid only.

I

Loop

I

Bat

I

DD

I

EE

PDo
PD1

V

OL

V

OH

V

IL

V

IH

I

IH

I

IL

±2

2
15
15

2

250

0.5 V

3.7

0.8 V

2.4
20

20

mA

mA
mA
mA

W

mW

V

V

µA
µA

= Open (On-hook)

R

Loop

On-Hook or Off-Hook
On-Hook or Off-Hook

Active
Stand-by/I dle

= 400µ A

I

OL

I

= 40µ A

OH

VIH = 5.0V

= 0.0V

V

IL

2-162

Preliminary Information MH88620IN

AC Electrical Characteristics*

1
1

8

12

‡

Max Units Test Comments

R

RMS

= 1400Ω

Loop

Term. 6.8µF +200Ω

V

2.0
8

V

RMS

dB

msec

= -48V

Bat

T-R load = 10Ωk min.
Dial Pulse Detection

msec

dB
dB
dB

dB
dB
dB

300-500Hz
500-2500Hz
2500-3400Hz

2000Hz, 1000Hz
2000Hz, 3000Hz
3400Hz

dBrnC
dBrnC

Characteristics Sym Min Typ

1

Analog Tx Gain (T-R to TX) 0 dB Externally adjustable

2

Analog Rx G ain (RX to T-R) 0 dB Externally adjustable

3

Ringing Capability 25 V

4

On-hook Transmission
Signal input lev el
Gain 4

5

SHK Rise Time
Fall time

6

2 Wire Termination Impedance 600 Ω Adjusta ble

7

Off-Hook Detect Threshold 10 mA

8

2-Wire Return Loss
600Ω at T-R

t

R

t

F

20
26
20

9

Longitudinal Balance

Longitudinal to Metallic 58

55
53

10

Longitudinal Current Capabilit y 40 mA 20mA per lead

11

Idle Channel Noise

12

Transhybrid Loss

Rx to T-R

T-R to Tx

N

CR

N

CX

THL

Tx gain 0dB
Rx gain 0dB

16
20
16

13

Analog Signal Overload Level at
TIP and RING 4 dBm

14

Ringing Signal Voltage 70 80 90 V

15

Ringing Frequency 2 0 25 30 Hz

16

Ring Trip Delay 100 ms

17

Absolute Gain variation -25 0 +. 25 dB 0dB m at T-R, 1kHz

18

Relative Gain, reference to 1kHz -2 0 +.2 dB 300-3400Hz

19

Power Supply Rejection Rat io

V

BAT

V

DD

V

EE

* AC Electrical Characteristics are over Recommended Operating Conditions unless otherwise stated.
‡ Typical figures are at 25C with nominal ± 5V supplies and are for design aid only.
Note: Test Conditions use a transmit and receive gain set to 0dB default and a Z

“Ref” indicates reference impedance which is equivalent to the termination impedance.
“Net” indicates ne two rk bala nce impe dance.

PSRR

24
24
24

30
30
30

value of 600Ω unless otherwi se sta ted.

in

dB
dB
dB

300-500Hz
500-2500Hz
2500-3400Hz

T-R = 900Ω

= -48V

V

BAT

RMS

dB 1kHz, 100mVpp

2-163

MH88620IN Preliminary Information

Transmit Gain (dB)

2-Wire to Tx 20log

(Tx/2-Wire)

+6.0 No Res istor
+4.0 38.3k Results in 0dB overall gain when used with

+3.7 32.4k

0.0 Connect GTX0 to GTX1

-3.0

-6.0 3.32k

-12.0 1.43k

Note 1: Overall gain refers to the receive path of PCM to 2-Wire.
Note 2: See Figure 2 for Application Circuit.

Receive Gain (dB)

Rx to 2-Wire 20log

(2-Wire/ Rx)

RTX Res istor (1%)

Value (Ω)

5.49k

RRX Resistor (1% )

Value (Ω)

Notes

Mitel A-law code c (i.e. M T89 65)

Notes

+6.0 No Resistor

0.0 Co nnect GR X0 to GRX1

-3.0 5.49k

-3.7 4.87k

-4.0

4.64k Results in 0dB o vera ll gain wh en us ed with

-6.0 3.32k

-12.0 1.43k

Note 1: Overall gain refers to the receive path of PCM to 2-Wire.
Note 2: See Figure 2 for Application Circuit.

75

I

Loop

60

(mA)

Mitel A-law codec (i.e. MT8965)

Constant

Voltage

Region

2-164

40

0

Graph 1 - I

R

Loop

(ohms)

Loop/RLoop

2k ohms

Characteristics

Preliminary Information MH88620IN

Functional Description

The SLIC uses a Transformerless electronic 2-4 wire
converter which can be connected to a Codec to
interface the 2 wire subscriber loops to a time
division multiplexed (TDM) pulse code modulated
(PCM) digital switching network. For analog
applications, the TXRX of the 2 wire converter can
be connected directly to an analog crosspoint switch,
such as the MT8816. Powering of the line is provided
through precision battery feed resistors. The
MH88620IN also contains control, signalling and
status circuitry which combines to provides a
complete functional solution, simplifying the
manufacture of line cards. This circuitry is illust rated
in the functional block diagram in Fig 1. The
MH88620IN is designed to be pin compatible with
Mitel’s MH88632, MH88625, MH88620, and
MH88628. This allows a common PCB design with
common gain, input impedance and network
balance.

Approvals

FCC part 68, CCITT, DOS CS-03, UL 1459, CAN/
CSA-22.2 N0. 225-M 9 0 and ANSI/EIA/T IA -4 6 4 -A ar e
system level safety standards and performance
requirements. As a component of a system, the
MH88620IN is designed to comply with the
applicable requirements of these specifications.

Battery Feed

The loop current for the subscriber equipment is
sourced through a pair of matched 200 ohm resistors
connected to the TIP and RING. The two wire loop is
biased such that the Ring lead is 2V above VBAT
(typically -46V) and the Tip lead is 2V below LGND
(typically -2V) during constant voltage mode.

provides for long loop capability regardless of the
current setting. Refer to graph 1.

The LCA (Loop Current Adjust) pin is an input to an
internal resistor driver network which generates a
bias voltage. The loop current is proportional to this
voltage. The loop c urrent can be set between 30 and
75 mA by various connections to the LCA pin as
illustrated in Table 5 and Figure 5. The loop current
during a fault condition will be limited to the constant
loop current programmed. Primary over current
protection is inherent in the current limiting feature of
the 200 ohm battery feed resistor. Refer to Graph 1.

Receive and Transmit Audio Path

The audio signal of the 2-wire is sensed diff erentially
across the 200 ohm feed resistor and is passed on to
a second differential amplifier stage in the 2W/4W
conversion block. This block sets the transmit gain
on the 4-wire side and cancels signals originating
from the rece ive in p ut .

Programmable Transmit and Receive Gain

Transm it Gain (Tip-Ring to Tx) and Receive Gain (Rx
to Tip-Ring) are programmed by connecting external
resistors (RRX and RTX) from GRX1 to AGND and
from GTX1 to AGND as indicated in Figure 2 and
Table 1 and 2. The programmable gain range is from

-12dB to +6dB; this wide range will accommodate
any loss plan. Alternatively, the default Receive Gain
of 0dB and Transmit Gain of 0dB can be obtained by
connecting GRX 0 and GRX1 and GTX0 to GTX1. In
addition, a Receive Gain of +6dB and Transm it Gain
of +6dB can be obtained by not connecting resis tors
RRX and RTX. For correct gain programming. the
MH88620IN’s Tip-Ring impedance (Z
the line term ination impedance.

) must match

in

The SLIC is designed for a nominal battery voltage
of -48Vdc and can provide the maximum loop current
of 75mA under this condition.

The interface circuit is designed to be operated down
to a maximum of 16mA dc, with a battery voltage of ­44V. The Tip and Ring output drivers can operate
within 2V of V

and LGND rails.

Bat

Loop Current Setting

The MH88620IN S LIC is a constant resistance with
constant voltage fallback design. This design feature

For optimum performance, resistors RRX should be
physically located as close as possible to the GRX1
input pin, and resistor RTX should be physically
located as close as possible to the GTX1 input pin.

Two Wire Port Termination Impedance

The AC termination of 600 ohms, of the 2W port is
set using active feedback paths to give the desired
relationship between the line voltage and the line
current. The loop current is sensed differentially
across the two feed resistors and converted to a
single ended signal. This signal is fed back to the

2-165

MH88620IN Preliminary Information

Tip/Ring dr iver circuitry such that impedance in the
feedbac k p ath gets r eflected to th e two wire port.

The MH88620IN’s Tip-ring impedance (Z
designed t o be 600
protection circuitry. For this requirement, Z1 and Z2
should be connected together on the PCB. To
accommodate the use of lower value PTC’s a series
resistance can be connected between Z1 and Z2.
For example, if two 8Ω PTCs are used, connect
340Ω between Z1 and Z2.

The design uses a 0.1 times impedance amplifier so
the 340Ω actually adds 34Ω of additional impedance
to the 550Ω (16 + 34 +550 = 600). For complex
impedance setting, a capacitor and/or resistor can
be connected between Z1 and Z2. For example, if
Return Loss is to be maximized for a Z
+2.2µF, a 0.22µF cap ca n be connected between Z1
and Z2.

Ω, when used with 25Ω PTC’s as

) is

in

of 600

in

Networ k Balan ce

Transhybrid loss is maximised when the line
termination impedance and SLIC network balance
are matched. The MH88620IN’s network balance
impedance can be set to Zin, or to a user selectable
value. Thus, the network balance impedance can be
set to any Indian or other international requirement.
An external Network Balance impedance is selected
which 0.1 times the impedance between N1 and
AGND. N2 to GND balances to 600 ohms.

Longitudinal Balance

The longitudinal balance specifies the degree of
common mode rejection in the 2 to 4 wire direction.
Precision laser trimming of internal resistors in the
hybrid ensures good overall longitudinal balance.

The interface circuitry can operate in the presence of
induced longitudinal currents of up to 40 mA RMS at
60 Hz.

DTMF

The DTMF tones are transmitted and received at the
4-wire port.

High voltage Capabili ty

Inherent in the thick-film process is the ability of the
substrate to handle high voltage. The standard Mitel
thick-film process provides dielectric strengths of
greater than 1000 VAC or 1500 VDC. The thick-film
process allows easy integration of surface mount
components such as the high volt age bipolar power
transistor line drivers. This allows for simpler, less
elaborate and less expensive protection circuitry
required to handle high voltage transients and fault
conditions caused by lightning, induced voltages and
power line crossings.

On-Hook Transmission

Off-Hook and Dial Pulse Detect ion

The SHK pin goes low when the DC-loop current
exceeds a specified level. The threshold level is
internally set by the bias voltage of the switch-hook
detect circuitry. Dial pulses can be detected by
monitoring the interruption rate at the SHK
These dial pulses would be debounced by the
system software.

pin.

Ring Trip Detecti on

The interface permits detection of an Off-Hook
condition during ringing. If the subscriber set goes
Off-Hook when the ringing signal has been applied,
the DC loop current flow will be detected within
approximately 100msecs and the SHK
low. The Ring relay is automatically disabled by the
internal hardware.

output will go

The MH88620IN provides for on-hook transmission
which supports features such as Automatic Number
Identification (ANI). The A NI information is a FSK or
DTMF signal originating from and sent by the C.O.
during the off period of the ringing v oltage being sent
to the subscr i ber’s set. The s ubscriber ’s set d e co d es
the identification signal and displays the calling
party’s number.

Applications

As shown in the application diagram, Figure 7a, the
ringing voltage, typically 80 V
VDC, is applied to the subscriber line through an
external relay, K1, Enabling of the relay is performed
by applying a logic high level to the relay driver
control input, RRC.

Figure 7b, shows how balanced ringing c an be
accommodated if required.

25Hz biased at -48

RMS

2-166

Preliminary Information MH88620IN

Protection Circuitry

Primary protection, from lightning strikes and AC line
faults, is normally located in the MDF (main
distribution feeder) which is located external to the
PABX or CO switching system. The primary
protection circuitry is normally housed in a 5-pin
connector and consists of either carbon blocks, with
spark gaps (older technology), gas discharge tubes
or high current semiconductor suppressors and
series heat c oils. The 5-pin module usually limits the
high voltage to approximately 300 to 500 volts bef ore
entering the switching system.

Secondary protection, in the switching system, is
required to further limit these high voltages/currents.

Secondary protection is normally implemented on
each line card and is designed to protect the SLICs
from permanent damage. The basic secondary high
voltage protection circuitry for the MH88620IN, as
illustrated in Figure 7, consists of PTC1, PTC2 and
clamping diodes D1 to D4. During a fault condition,
the diodes clamp the overvolt Ground and -V
PTC1 and PTC2 current limit as their resistance
increases with power dissipation caused by the over­a voltage/over-current condition. The ground that D1
and D3 are connect ed to, must be an EDG (energy
dumping ground) which is connected to the chassis

Bat

or system ground. This is a seperate conductor from
LPGND or AGND on the line care PCB. D2 and D4
conduct the energy into a -V
seperate conductor from the -V

supply which is a

Bat

feed supply to the

Bat

SLICs. A power MOSFET circuit as shown in Figure
8, can be used to divert the energy normally dumped
into - V

, the EDG conductor. Usually one MOSFET

Bat

circuit can be used for 16 SLICs or per line card.

Depending on the additional level of protection
required, PRO1 and/or PRO2 protectors may be
used. These are used to protect the SLICs Ring
sense resistor and/or Ring generator from being
damaged if a fault condition occurs during the
application of Ringing to the line. PRO2 can be
implemented using two back to back zener diodes, or
an equivalent transient suppressor. The clamping
voltage should be >16 Vdc and <26Vdc. PRO2 may
not be required depending on the value and power
dissipation of PRO1.

Loop Length

.

The MH88620IN can accommodate loop lengths of
up to 2000 ohms minimum (including the subscriber
equipment). This corresponds to approximately 8km
using #26 AWG twisted pair or 15km using #24 AWG
twisted pair.

MH88620IN

24

Z2

R

Internal

5500 Ω

23

Z1

A.

Notes

a) to accommodate the use of 2 x 25Ω PTCs, connect Z1 and Z2 together, Zin = 600Ω.
b) to accommodate the use of 2 x 8Ω PTCs, c o nn ec t 3 40 Ω between Z1 and Z2 = 600Ω.
c) to accommodate the use of 2 x 25Ω PTCs, connect 0.22µF betwee n Z1 an d Z2 = 6.0 Ω + 2 .2 µF.

MH88620IN

Z2

R

Internal
5500 Ω

Z1

B.

24

23

External

0.22µF

MH88620IN

Internal

5500 Ω

Figure 3 - Input Impedance (Zin) setting

24

Z2

R

Ζ1

R

External

340Ω

C.

2-167

MH88620IN Preliminary Information

MH88620IN

R Internal
9000 Ω

Notes:

1) The 10xZin network must be set to 10 x the desired input Z

2) The 10 x NETBAL network must be set to10x the desired network balance.

3) Make connection between N1 and compone nt as short as possible.

N2

N1

10 x

NETBAL

(impedance).

in

RP

N1

ZNETBAL = 0.1 x

where S = j x w
and w = 2 x π x f

Example:

If RS =0Ω, RP = 800Ω, CP=.5nF

Then the network balance is 800Ω in

parallel with 50nF.

CP

RS

RS +

[

1/RP + (SxCP)

1

Figure 4 - External Network Balance Setting

Loop Current LCA Pin Connection Reference Fig#

20 Connect 10kΩ from LCA to + 5 V. 5a
25 Connect 16kΩ from LCA to + 5 V. 5a
30 Connect 36kΩ from LCA to + 5 V. 5a
35 Leave LCA open circuit. 5c
40 Connect 24kΩ from LCA to -5V. 5b
45 Connect 10kΩ from LCA to -5V. 5b
50 Connect 5.6kΩ from LCA to - 5 V. 5b
55 Connect 2.4kΩ from LCA to - 5 V. 5b
60 Connect 1.3kΩ from LCA to - 5 V. 5b
65 Connect 680kΩ from LCA to -5 V. 5b
70 Connect from LCA to -5V. 5d

]

2-168

5a

LCA

+5V

Ta ble 5 - Lo op Cur rent Se tting

LCA

R

-5V

5b

5c

Figure 5 - Loop Curren t Setting

LCA

LCA

-5V

5d

Preliminary Information MH88620IN

MH88620IN

Z

Z

10kΩ

Transmit Gain

25

TX

28

GTX1

RX

27

26

30

29

GTX0

10kΩ

Z

Z

10kΩ

GRX1

GRX0

10kΩ

RTX

RRX

(Tip-Ring to Tx)

AV= -20log 0.5+3k

Example

RTX=38kΩ; AV= +4dBV

Receive Gain:

(RX to Tip-Ring)
AV= -20log 0.5 + 5k

Example:

RRX= 4.6kΩ; AV= -4dBV

:

Ω

RTX

RRX

]

Ω

]

[

[

Figure 6 - Gain Pro gr am min g with Ex te rnal Com p one nts

2-169

MH88620IN Preliminary Information

SYSTEM

GROUND

K1

+5V

-5V

V

DD

V

EE

TERM

-V

Bat

Bat

RX

GRX0
GRX1

LCA

V

VR

VX

SDo

CSTi FDi

-5 +5

MT896X

CODEC

FLi

Timeslot

C2i

DSTo

DSTi

CA

Assignment

AGND

TF1

TF2

P
R

O
T
E
C
T

I
O
N

TIP

RING

RF1
RF2

TX

MH88620IN

GTX0

GTX1

SHK

UD

Z1

Z600

RNGC

VRLY

RRD

REVC

Circuit

C2i

F1i

Status

Mux

Circuit

K1

CA

CSTo

2-170

-V

Bat

90V

RS1

RS2

NS

20Hz

RMS

Figure 7a - OPS SLIC Con fig urati on Appl ic atio ns Ci rcui t

Preliminary Information MH88620IN

-V

Bat

CSTi FDi

-5 +5

C2i

SYSTEM

GROUND

+5V

-5V

V

DD

V

EE

TERM

Bat

RX

GRX0

GRX1

LCA

V

VR

VX

SUBSCRIBER 1

SDo

CODEC

FLi

Timeslot

DST o

DSTi

CA

Assignment

AGND

TF1

TF2

TX

MH88620IN

GTX0

GTX1

SHK

Circuit

Status

Mux

CA

F1iC2i

CST o

Circuit

Z1

P
R
O

T
E

C
T

I

O
N

TIP

RING

RF1

Z2

RNGC

VRLY

RRD
REVC

K1

45Vrms

20Hz

~

+

~

+

-V

Bat

45Vrms

20Hz

RF2

NS

Figure 7b - OPS SLIC Con fig uration Appl ic atio ns Cir cui t - Balanced Ring i ng

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MH88620IN Preliminary Information

GND

D1

PTC1

PTC2

PRO1

D2

D3

D4

V

Bat

GND

V

Bat

T

R

Suggested Components

PRO1 Solid State Transient Suppressor, e.g., TISP2300L, P2703AB, MOV’s

or dio de clamps D 1- D4 to V

and LPGND

Bat

PTC1, PTC2 Typical 25 Ω

Figure 8 - Suggested Protection Circuit

MH88620IN

Side View

0.002

0.010 +
(0.25 +

0.05)

Notes:

1) Not to scale

2)Dimensions in inch es).

3) (Dimensions in millimetres).
*Dimensio ns to centre of pin &

tolerance non ac cumulati ve.

0.080 Max
(2.0 Max)

0.12 Max
(3.1 Max )

0.02

0.58+

(14.7+

0.05 +
(1.3 +

0.01

0.5)

0.5)

*

0.05 +

(1.3 +

1

2

3

43940

***

0.02

0.05)

Figure 9 - Mechanical Data

0.020 +
(0.51 +

4.20 + 0.020

0.5)

(50.8 +

0.05

0.13)

0.100 +

(2.54 +

0.10

0.13 )

0.18 +

(4.6 +

0.02

0.5)

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