Datasheet MTH88437AD-P, MTH88437AD-PI, MTH88437AS-PI, MTH88437AS-P Datasheet (MITEL)

1

Features

• FAX and Modem interface (V.34/V.34+)

• Designed to work at data rates up to 56kbits

• External programmable line and network
balance impedances

• Programmable DC termination characteristics

• IEC950 recognised component

• Transformerless 2-4 Wire conversion

• Integral Loop Switch

• Dial Pulse and DTMF operation

• Accommodates parallel phone detection

• Line state detection outputs:

-loop current/ringing voltage/line voltage

• +5V operation, low on-hook power (25mW)

• Full duplex voice and data transmission

• On-Hook reception from the line

• Meets French current limit requirements

• Conforms to German dial pulse standards

• Approvable to UL 1950

• Industrial Temperature Range Available

Applications

Interface to Central Office or PABX line for:

• FAX/Modem

• Electronic Point of Sale

• Security System

• Telemetry

• Set Top Boxes

Description

The Mitel MH88437 Data Access Arrangement
(D.A.A.) provides a complete interface between
audio or data transmission equipment and a
telephone line. All functions are integrated into a
single thick film hybrid module which provides high
voltage isolation, very high reliability and optimum
circuit design, needing a minimum of external
components.

The impedance and network balance are externally
programmable, as are the DC termination
characteristics, making the device suitable for most
countries worldwide.

Figure 1 - Functional Block Diagram

Opto-

Isolation

Logic Input

Buffer

Isolation

Isolation

Isolation

Analog

Buffer

Analog

Buffer

Buffer

THL cancellation

impedance

matching

circuit

Isolation Barrier

VCC
AGND

LC
VR+

VX

RV

TIP

RING

User Connections

Network Connections

Input Buffer

&

VLOOP1

Ring & Loop

Line Termination

VLOOP2

VR­NB1

NB2

LOOP

LCD

ZA

RS

VBIAS

and line

CL

DS5060 ISSUE 4 October 1998

Package Information

MH88437AD-P 28 Pin DIL Package
MH88437AS-P 28 Pin SM Package

0˚C to 70˚C

MH88437AD-PI Ind. Temp. DIL Variant

-40˚C to +80˚C

MH88437AS-PI Ind. Temp. SM Variant

-40˚C to + 80˚C

MH88437-P

Data Access Arrangement

Advance Information

MH88437-P Advance Information

2

Figure 2 - Pin Connections

Pin Description

Pin # Name Description

1 NB1 Network Balance 1. External passive components must be connected between this pin and

NB2.

2 NB2 Network Balance 2. External passive components must be connected between this pin and

NB1.
3 VR+ Differential Receive (Input). Analog input from modem/fax chip set.
4 VR- Differential Receive (Input). Analog input from modem/fax chip set.
5VXTransmit (Output). Ground referenced (AGND) output to modem/fax chip set, biased at

+2.0V.
6LCLoop Control (Input). A logic 1 applied to this pin activates internal circuitry which provides

a DC termination across Tip and Ring. This pin is also used for dial pulse application.
7ZALine Impedance. Connect impedance matching components from this pin to Ground

(AGND).
8 AGND Analog Ground. 4-Wire 0V reference connect to mains earth (ground).
9VCCPositive Supply Voltage. +5V.

10 VBIAS Internal Reference Voltage. +2.0V reference voltage. This pin should be decoupled

externally to AGND, typically with a 10µF 6.3V capacitor.

11 LOOP Loop (Output). The output voltage on this pin is proportional to the line voltage across Tip -

Ring, scaled down by a factor of 50.

12,

14

IC Internal Connection. No connection should be made to this pin externally.

13 RS Ringing Sensitivity. Connecting a link or resistor between this pin and LOOP (pin 11) will

vary the ringing detection sensitivity of the module.

15 LCD Loop Condition Detect (Output). Indicates the status of loop current.
16 RV Ringing Voltage Detect (Output). The R V output indicates the presence of a ringing voltage

applied across the Tip and Ring leads.

17 CL Current Limit. A logic 0 applied to this pin activates internal circuitry which limits the loop

current.

18 NP No Pin. Isolation Barrier, fitted, no pin fitted in this position.
19 NP No Pin. Isolation barrier, no pin fitted in this position

CL

IC

LC

IC

TIP

AGND

RING

RV

ZA

VX

VR-

VCC

1
2
3
4
5
6
7
8
9
10
11
12
13
14

28
27
26
25
24
23
22
21
20
19
18
17
16
15

VR+

NB1
NB2

VBIAS

LOOP

IC

RS

IC

VLOOP1
VLOOP2
IC

SC
SC

NP
NP

LCD

Advance Information MH88437-P

3

20,23

26

IC Internal Connection. No connection should be made to this pin externally.

21,22 SC Short Circuit. These two pins should be connected to each other via a 0Ω link.

24 VLOOP2 Loop Voltage Control Node 2. Used to set DC termination characteristics.
25 VLOOP1 Loop Voltage Control Node 1. Used to set DC termination characteristics.
27 RING Ring Lead. Connects to the “Ring” lead of the telephone line.
28 TIP Tip Lead. Connects to the “Tip” lead of the telephone line.

Pin Description (continued)

Pin # Name Description

Functional Description

The device is a Data Access Arrangement (D.A.A.). It
is used to correctly terminate a 2-Wire telephone
line. It provides a signalling link and a 2-4 Wire line
interface between an analog loop and subscriber
data transmission equipment, such as Modems,
Facsimiles (Fax’s), Remote Meters, Electronic Point
of Sale equipment and Set Top Boxes.

Isolation Barrier

The device provides an isolation barrier capable of
meeting the supplementary barrier requirements of
the international standard IEC 950 and the national
variants of this scheme such as EN 60950 for
European applications and UL 1950 for North
American applications.

External Protection Circuit

An External Protection Circuit assists in preventing
damage to the device and the subscriber equipment,
due to over-voltage conditions. See Application Note
MSAN-154 for recommendations.

Suitable Markets

The MH88437 has features such as programmable
line and network balance impedance, programmable
DC termination and a supplementary isolation
barrier. For countries that do not need to meet the
French and German requirements there is a pin for
pin compatible device the MH88435.

There are, however, a small number of countries with
a 100MΩ leakage requirement that this device does
not meet. These are Belgium, Greece, Italy,
Luxembourg, Spain and Poland. Although
Luxembourg will now accept TBR21 and there are
exceptions to the Italian specification, in most

applications the MH88437 will comply with
Luxembourg and Italian specifications. For approval
in Denmark and Sweden the TRB21 route is
recommended.

Approval specifications are regularly changing and
the relevant specification should alw ays be consulted
before commencing design.

Line Termination

When Loop Control (LC) is at a logic 1, a line
termination is applied across Tip and Ring. The
device can be considered off-hook and DC loop
current will flow. The line termination consists of both
a DC line termination and an AC input impedance. It
is used to terminate an incoming call, seize the line
for an outgoing call, or if it is applied and
disconnected at the required rate, can be used to
generate dial pulses.

The DC termination resembles approximately 300Ω
resistance, which is loop current dependent.
Furthermore, it can be programmed to meet different
national requirements. For normal operation
VLOOP3 should be open circuit and a resistor (R2)
should be fitted between VLOOP1 and VLOOP2, as
shown in Figure 4.

The approval specification will give a DC mask
characteristic that the equipment will need to comply
to. The DC mask specifies the amount of current the
DAA can sink for a given voltage across tip and ring.
Graph 1 shows how the voltage across tip and ring
varies with different resistors (R2) for a given loop
current.

Network Balance

The network balance impedance of the device can
be programmed by adding external components By

MH88437-P Advance Information

4

applying a logic 0 to Pin 17, CL, the loop current will
be limited to below 60mA as required in France and
the European TBR21 specification. For all other
countries where current limiting is not required, CL
should be set to 1.

The AC input impedance should be set by the user to
match the line impedance.

Input Impedance

The MH88437 has a programmable input impedance
set by fitting external components between the ZA
pin and AGND.

For complex impedances the configuration shown in
Figure 4 (below) is most commonly found.

Figure 4 - Complex Impedances

To find the external programming components for
configuration 4, the following formula should be
used:

Zext = [(10 x R1)-1k3]+[(10 x R2)//(C1/10)]

e.g. If the required input impedance = 220Ω + (820Ω/
/115nF), the external network to be connected to ZA
will be:

ZA = 900Ω + (8k2Ω//12nF)
Where the input impedance (Z) = 600R the equation

can be simplified to:

ZA = (10 x Z) - 1k3Ω

ZA = 4k7Ω

Note: A table of commonly used impedances can be
found in the DAA Application’s document MSAN-154.

Where Zext = external network connected between
ZA and AGND and Zint = 1.3kΩ (internal resistance)

between NB1 and NB2. For countries where the
balance impedance matches the line impedance, a
16kΩ resistor should be added between NB1 and
NB2.

R1

R2

C1

Figure 3 - DC Programming Capability

Iloop=15mA

Iloop=20mA

Iloop=26mA

35

30

10

5

0

25

20

15

40

50 150 250 350 450 550 650 750 850 950

R2(kOhms)

V(t-r)

Advance Information MH88437-P

5

Ringing Voltage Detection

The sensitivity of the ringing voltage detection
circuitry can be adjusted by applying an external
resistor (R7, Figure 5) between the RS and LOOP
pins. With a short circuit, the threshold sensitivity is
~10Vrms, therefore R7 = 30kΩ x (Desired threshold
voltage - 10Vrms).

Example: 300kΩ gives ~20Vrms and 600kΩ gives
~30Vrms.

An AC ringing voltage across Tip and Ring will cause
RV to output TTL pulses at the ringing frequency,
with an envelope determined by the ringing cadence.

Parallel Phone and Dummy Ringer

An external parallel phone or dummy ringer circuit
can be connected across Tip and Ring as shown in
Figure 5. A Dummy Ringer is an AC load which
represents a telephone’s mechanical ringer.

In normal circumstances when a telephone is On­Hook and connected to the PSTN, its AC (Ringer)
load is permanently presented to the network. This
condition is used by many PTT’s to test line
continuity, by placing a small AC current onto the line
and measuring the voltage across tip (A) and ring
(B).

Today’s telecom equipment may not have an AC load
present across tip and ring (e.g. modems), therefore
any testing carried out by the PTT will see an open
circuit across tip and ring. In this instance the PTT
assumes that the line continuity has been damaged.

To overcome this problem many PTT’s specify that a
"Dummy Ringer" is presented to the network at all
times. Ideally its impedance should be low in the
audio band and high at the ringing frequencies (e.g.
25Hz). Note that the requirement for the "Dummy
Ringer" is country specific.

Parallel phone detection is used mostly in set-top
box applications. This is when a modem call will
need to be disconnected from the central office by
the equipment when the parallel phone is in the off­hook state. This is to allow the subscriber to make
emergency calls.

To detect this state, additional circuitry will be
required. Refer to Application Note MSAN-154.

2-4 Wire Conversion

The device converts the balanced 2-Wire input,
presented by the line at Tip and Ring, to a ground
referenced signal at VX, biased at 2.0V. This
simplifies the interface to a modem chip set.

Conversely, the device converts the differential signal
input at VR+ and VR- to a balanced 2-Wire signal at
Tip and Ring. The device can also be used in a
single ended mode at the receive input, by leaving
VR+ open circuit and connecting the input signal to
VR- only. Both inputs are biased at 2.0V.

During full duplex transmission, the signal at Tip and
Ring consists of both the signal from the device to
the line and the signal from the line to the device.
The signal input at VR+ and VR- being sent to the
line, must not appear at the output VX. In order to
prevent this, the device has an internal cancellation
circuit, the measure of this attenuation is Transhybrid
Loss (THL).

The MH88437 has the ability to transmit analog
signals from Tip and Ring through to VX when on­hook. This can be used when receiving caller line
identification information.

Transmit Gain

The Transmit Gain of the MH88437 is the gain from
the differential signal across Tip and Ring to the
ground referenced signal at VX. The internal
Transmit Gain of the device is fixed as shown in the
AC Electrical Characteristics table. For the correct
gain, the Input Impedance of the MH88437, must
match the specified line impedance.

By adding an external potential divider to VX, it is
possible to reduce the overall gain in the application.
The output impedance of VX is approximately 10Ω
and the minimum resistance from VX to ground
should be 2kΩ.

Example: If R3 = R4 = 2kΩ, in Figure 5, the overall
gain would reduce by 6.0dB.

Receive Gain

The Receive Gain of the MH88437 is the gain from
the differential signal at VR+ and VR- to the
differential signal across Tip and Ring. The internal
Receive Gain of the device is fixed as shown in the
AC Electrical Characteristics table. For the correct

MH88437-P Advance Information

6

gain, the Input Impedance of the MH88437 must
match the specified line impedance.

With an internal series input resistance of 47kΩ at
the VR+ and VR- pins, external series resistors can
be used to reduce the overall gain.

Overall Receive Gain = 0dB+20log (47kΩ/
(47kΩ+R5)).

For differential applications R6 must be equal to R5
in Figure 5.

Example: If R5 = R6 = 47k in Figure 3, the overall
gain would reduce by 6.0dB.

Supervisory Features

The device is capable of monitoring the line
conditions across Tip and Ring, this is shown in
Figure 5. The Loop Condition Detect pin (LCD),
indicates the status of the line. The LCD output is at
logic 1 when loop current flows, indicating that the
MH88437 is in an off hook state. LCD will also go
high if a parallel phone goes off-hook. Therefore, line
conditions can be determined with the LC and the
LCD pins.

The LOOP pin output voltage VLOOP is proportional
to the line voltage across Tip and Ring scaled down
by a factor of 50 and offset by 2.0V(t-r). With the aid
of a simple external detector the LC, LCD and LOOP
pins can be used to generate the signals necessary
for parallel phone operation, e.g. with a Set Top Box.
See MSAN-154 for further details.

When the device is generating dial pulses, the LCD
pin outputs TTL pulses at the same rate. The LCD
output will also pulse if a parallel phone is used to
dial and when ringing voltage is present at Tip and
Ring.

Mechanical Data

See Figures 12, 13 and 14 for details of the
mechanical specification.

Advance Information MH88437-P

7

Figure 5 - Typical Application Circuit

TIP

NB2

RING

VX

VR+

RV

LC

AGND

VCC

TIP

RING

C2

+5V

9

8

6

16

5

3

27

28

Analog

Input

Analog

Ringing Voltage Detect Output

Loop Control Input

MH88437

+

Output

C4

C1

Notes:

R1 & C1: Dummy Ringer, country specific

ZA
7

Zext

R2: DC Mask Resistor 120kΩ typical

R1

25 24

VLOOP1

VLOOP2

VR-

4

Analog

Input

R2

LCD

15

Loop Current Detect Output

NB1

ZB: Network Balance Impedance

R3

R5

R6

R4

R5 = R6: Receive Gain Resistors typically 100k

R3 & R4: Transmit Gain Resistors ≥ 2k2

C3

+

10

VBIAS

typically 0.39µF, 250V & 3kΩ

C2 & C3 = 10µF 6V
C7 & C8 = 39nF for 12kHz filter and 22nF for
16KHz filter. These can be left off if meter pulse
filtering not required.
Zext: External Impedance
D1 Zener Diode 6V2
L1, L2 = 4.7mH RDC<10Ω. These can be left
off if meter pulse filtering not required.

D1

C7

L1

L2

C8

13

11

RS

LOOP

ZB

1

2

C5

C6

C4, C5 & C6 = 1µF coupling capacitors
R7 = 620kΩ (30V RMS ringing sensitivity)

CL

D2

D2 = Teccor P2703 Protection

R7

= Ground (Earth)

21

22

1)

2)

3)

4)

5)

6)

7)

8)

9)

10)

11)

12)

13)

MH88437-P Advance Information

8

.

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

‡ Typical figures are at 25˚C with nominal +5V supply and are for design aid only

† Electrical Characteristics are over Recommended Operating Conditions unless otherwise stated.
‡ Typical figures are at 25°C with nominal + 5V supplies and are for design aid only.
Note 1: Low Loop current operation depends on value of resistor connected between V

Loop

1 and V

Loop

2.
Note 2: This is equivalent to 10MΩ leakage Tip/Ring to Ground.
Note 3. Refer to EIA/TIA 464 Section 4.1.1.4.4

Absolute Maximum Ratings* - All voltages are with respect to AGND unless otherwise specified.

Parameter Sym Min Max Units Comments

1 DC Supply Voltage V

CC

-0.3 6 V

2 Storage Temperature T

S

-55 +125 ˚C

3 DC Loop Voltage V

TR

-110 +110 V

4 Transient loop voltage V

TR

300 V 1ms On hook

5 Ringing Voltage V

R

150 Vrms VBAT = -56V

6 Loop Current I

LOOP

60
90

mA
mA

CL=0 V

TIP-RING

≤40V

CL=1

7 Ring Trip Current I

TRIP

180 mArms 250ms 10% duty cycle or

500ms single shot

Recommended Operating Conditions

Parameter Sym Min Typ‡Max Units Test Conditions

1 DC Supply Voltages V

CC

4.75 5.0 5.25

V

2 Operating Temperatures

Industrial Temperature

T

OP

0

-40

25 70

+85

˚C

3 Ringing Voltage V

R

75 90 Vrms VBat = -48V

Loop Electrical Characteristics

†

Characteristics Sym Min Typ‡Max Units Test Conditions

1 Ringing Voltage

No Detect
Detect

VR

14

7Vrms

Vrms

Externally Adjustable

2 Ringing Frequency 15 68 Hz
3 Operating Loop Current 15 60

80

mAmACL=0 V

TIP-RING

≤40V

CL=1 (see Note 1)

4 Off-Hook DC Voltage

6.0

6.0

7.8

V
V
V

Externally Adjustable
I

LOOP

=15mA)

I

LOOP

=20mA) (Note 3)

I

LOOP=

26mA)

where R2 = 110kΩ

5 Leakage Current

(Tip or Ring to AGND)

10

7

µAmA100V DC (see Note 2)

1000V AC

6 Leakage Current on-hook

(Tip to Ring)

9

18

10
20

µΑ V

BAT

(= -50V)

V

BAT

(= -100V)

7 Dial Pulse Detection ON

OFF

0
0

+1
+1

+2
+2

msmsDial pulse delay

8 Loop Condition Detect Threshold

Off-Hook 5 16 V

Voltage across tip and
ring

Advance Information MH88437-P

9

)

† Electrical Characteristics are over Recommended Operating Conditions unless otherwise stated.
‡ Typical figures are at 25°C with nominal + 5V supplies and are for design aid only.

Variations from Standard Loop Electrical Characteristics
(MH88437AD-PI/MH88437AS-PI) (+70˚C to +85˚C)

Characteristics Sym Min Typ Max Units Test Conditions

1 Operating Loop Current 16 60

80

mA
mA

CL\=0
CL\=1

DC Electrical Characteristics

†

Characteristics Sym Min Typ‡Max Units Test Conditions

1 Supply Current I

CC

5mAV

DD

(= 5.0V, On-hook)

2RV,

LCD

Low Level Output Voltage
High Level Output Voltage

V

OL

V

OH

2.4

0.4 V
V

IOL= 4mA
IOH= 0.4mA

3 LC Low Level Input Voltage

High Level Input Voltage
Low Level Input Current
High Level Input Current

V

IL

V

IH

I

IL

I

IH

2.0
0

350

0.8
60

400

V
V

µAµAVIL= 0.0V

VIH= 5.0V

4 VR+

VR-

DC common mode VCM 0 2 VCC VDC Use coupling caps for

higher voltages and single
ended

AC Electrical Characteristics

†

Characteristics Sym Min Typ

‡

Max Units Test Conditions

1 Input Impedance

VR-

VR+

47k
94k

Ω
Ω

2 Output Impedance at VX 10 Ω
3 Receive Gain (VR to 2-Wire) -1 0 1

dB

Test circuit (Figure 8)
Input 0.5V at 1kHz

4 Frequency Response Gain

(relative to Gain @ 1kHz)

-0.5 0 0.5 dB

ILOOP = 15-60mA

300Hz to 3400 Hz

5 Signal Output Overload Level

at 2-Wire

at VX

0
0

dBm
dBm

THD < 5% @ 1kHz
I

LOOP

= 25-60mA

VCC = 5V

6 Signal/Noise & Distortion

at 2-Wire
at VX

SINAD

70
70

dB
dB

Input 0.5V at 1kHz

I

LOOP

= 25-60mA

300-3400Hz

7 Power Supply Rejection Ratio

at 2-Wire
at VX

PSRR

25
25

40
40

dB
dB

Ripple 0.1Vrms 1kHz on
V

DD

8 Transhybrid Loss THL 16 25 dB Test circuit (Figure 8)

300-3400Hz at V

R

9 2-Wire Input Impedance Zin Note 3 Ω @ 1kHz

MH88437-P Advance Information

10

† Electrical Characteristics are over Recommended Operating Conditions unless otherwise stated.
‡ Typical figures are at 25°C with nominal + 5V supplies and are for design aid only.

10 Return Loss at 2-Wire

(Reference 600Ω)

RL

14
20
18

24
24
24

dB
dB
dB

Test circuit(Figure 9)
200-500Hz
500-2500Hz
2500-3400Hz

11 Longitudinal to Metallic Balance

Metallic to Longitudinal Balance

Nc

46
46

60
40

58
53

dB
dB

dB
dB

Test circuit (Figure 10)
300-1000Hz
1000-3400Hz
Test circuit (Figure 11)
200-1000Hz
1000-4000Hz

12 Idle Channel Noise

at 2-Wire

at VX

at 2-Wire

at VX

15
15

-65

-65

2020dBrnC

dBrnC

dBm
dBm

Cmess filter
300-3400Hz filter

13 Transmit Gain (2-Wire to VX)

Off-Hook
On-Hook

-1 0
0

+1 dB

dB

Test circuit (Figure 7)
Input 0.5V @ 1kHz

LC = 0V

14 Frequency Response Gain

(relative to Gain @ 1kHz)

-0.5

-0.5

0
0

0.5

0.5

dB
dB

300Hz
3400Hz

15 Intermodulation Distortion

products at VX and 2W

IMD 75 dB I

LOOP

= 25-60mA
F1 = 1kHz at -6dBm
F2 = 800Hz at -6dBm
Total signal power =

-3dBm

16 Distortion at VX due to near end

echo
(300Hz - 3400Hz bandwidth)

75 dB I

LOOP

= 25-60mA
F1 = 1kHz at -6dBm
F2 = 800Hz at -6dBm
Total signal power =

-3dBm

17 Common Mode Rejection at VX CMR 50 dB Test circuit (Figure 10)

1-100Hz Note 4

18 Common Mode overload CML 100V V

pk-pk

Test circuit (Figure 10)
1-100Hz Note 4

Variations from Standard AC Electrical Characteristics
(MH88437AD-PI/MH88437AS-PI) (-40˚C to 0˚C)

Characteristics Sym Min Typ Max Units Test Conditions

1 Receive Gain (VR to 2-Wire) -1.1 dB Test circuit (Figure 8)

Input 0.5V at 1kHz

2 Frequency Response Gain

(Relative to Gain @ 1kHz)

-1.2 dB I

LOOP

= 16-60mA

300Hz to 3400Hz

3 Transhybrid Loss THL -12

-15

dB 300Hz to 1kHz

1kHz to 3400Hz

AC Electrical Characteristics† (continued)

Characteristics Sym Min Typ

‡

Max Units Test Conditions

Advance Information MH88437-P

11

Figure 6 - Test Circuit 1

Figure 7 - Test Circuit 2

DUT

3
4
5

25

VX

AGNDRV

VR+
VR-

TIP

NB1

RING

24

23

22

21

82K

VLOOP1

LC

5V

1K

VLOOP5
VLOOP4
VLOOP3

VLOOP2

VCC ZA

NB2

10uF

VBIAS

10

27

2

28
1

16K

616

8

7

9

4.7K

LOOP

RS

LCD

11

13

15

ILOOP

5V

+

= Ground (Earth)

Vs

I=20mA

10H 500

Ω

-V

100uF

10H 500Ω

+

100uF

+

Gain = 20 * Log (VX / Vs)

DUT

3
4

5

25

VX

AGNDRV

VR+
VR-

TIP

NB1

RING

24

23

22

21

82K

VLOOP1

LC

5V

1K

VLOOP5
VLOOP4
VLOOP3

VLOOP2

VCC ZA

NB2

10uF

VBIAS

10

27

2

28
1

16K

616

8

7

9

4.7K

5V

LOOP

RS

LCD

11

13

15

Impedance = Zin

+

= Ground (Earth)

MH88437-P Advance Information

12

Figure 8 - Test Circuit 3

Figure 9 - Test Circuit 4

100uF

Zin

10H 500Ω

-V

I=20mA

10H 500

Ω

100uF

+

+

Gain = 20 * Log (V(Zin) / Vs)

DUT

3
4
5

25

VX

AGNDRV

VR+
VR-

TIP

NB1

RING

24

23

22

21

82K

VLOOP1

LC

5V

1K

VLOOP5
VLOOP4
VLOOP3

VLOOP2

VCC ZA

NB2

10uF

VBIAS

10

27

2

28
1

16K

616

8

7

9

4.7K

5V

LOOP

RS

LCD

11

13

15

Vs

+

= Ground (Earth)

100uF

-V
10H 500

Ω

I=20mA

V1

300Ω

300Ω

Vs = 0.5V

+

100uF

+

Return Loss = 20 * Log (V1 / Vs)

10H 500Ω

Zin

DUT

3
4
5

25

VX

AGNDRV

VR+
VR-

TIP

NB1

RING

24

23

22

21

82K

VLOOP1

LC

5V

1K

VLOOP5
VLOOP4
VLOOP3

VLOOP2

VCC ZA

NB2

10uF

VBIAS

10

27

2

28
1

16K

616

8

7

9

4.7K

LOOP

RS

LCD

11

13

15

5V

+

= Ground (Earth)

Advance Information MH88437-P

13

Figure 10 - Test Circuit 5

Figure 11 - Test Circuit 6

100uF

Vs = 0.5V

300

Ω

300Ω

-V

10H 500Ω

I=20mA

+

+

100uF

Long. to Met. Balance = 20 * Log (V1 / Vs)

V1

10H 500

Ω

DUT

3
4
5

25

VX

AGNDRV

VR+
VR-

TIP

NB1

RING

24

23

22

21

82K

VLOOP1

LC

5V

1K

VLOOP5
VLOOP4
VLOOP3

VLOOP2

VCC ZA

NB2

10uF

VBIAS

10

27

2

28
1

16K

616

8

7

9

4.7K

5V

LOOP

RS

LCD

11

13

15

CMR = 20 * Log (VX / Vs)

+

= Ground (Earth)

-V

10H 500Ω

I=20mA

300Ω

300Ω

V1

Vs

100uF

+

100uF

+

Met. to Long. Balance = 20 * Log (V1 / Vs)

10H 500

Ω

510Ω

DUT

3
4
5

25

VX

AGNDRV

VR+
VR-

TIP

NB1

RING

24

23

22

21

82K

VLOOP1

LC

5V

1K

VLOOP5
VLOOP4
VLOOP3

VLOOP2

VCC ZA

NB2

10uF

VBIAS

10

27

2

28
1

16K

616

8

7

9

4.7K

5V

LOOP

RS

LCD

11

13

15

+

= Ground (Earth)

MH88437-P Advance Information

14

Figure 12 - Mechanical Data for 28 Pin DIL Hybrid

Figure 13 - Mechanical Data for 28 Pin Surface Mount Hybrid

Notes:

1) Not to scale

2) Dimensions in inches.

(Dimensions in millimetres)

1.42 Max

(36.1 Max)

0.162 Max (4.12 Max)

0.05 Typ

(1.27 Typ)

0.020 + 0.005

(0.5

+ 0.13)

0.063 Max

0.260

+0.015

(25.4 Typ)

1.05 Max

(26.7 Max)

* Dimensions to centre of pin.

1.00 Typ

0.27 Max
(6.9 Max)

0.08 Typ (2 Typ)

0.100

+0.010

(2.54

+0.25)

*

*

1

*

(1.6 Max)

(6.6+0.38)

3) Pin tolerances are non-accumulative.

4) Recommended soldering conditions:
Wave Soldering - Max temp at pins 260˚C for 10 secs.

0.300+0.010
(7.62+0.25)

*

Notes:

1) Not to scale

2) Dimensions in inches.

(Dimensions in millimetres)

1.42 Max

(36.1 Max)

0.162 Max (4.11 Max)

0.063 Max

* Dimensions to centre of pin.

1

(1.6 Max)

3) Pin tolerances are non-accumulative.

4) Recommended soldering conditions:

0.300+0.010
(7.62+0.25)

*

(25.15 Typ)

0.060 Typ

(1.52 Typ)

0.99 Typ

0.9 + 0.015
(2.3

+ 0.38)

0.265 Max
(6.73 Max)

0.100+0.010
(2.54+0.25)

*

0.020 + 0.005
(0.5 + 0.13)

0.05 Typ

(1.27 Typ)

*

Max reflow temp: 220˚C for 10 secs.

1.15 Max

(29.2 Max)

Advance Information MH88437-P

15

Figure 14 - Recommended Footprint for 28 Pin Surface Mount Hybrid

0.10

(2.54)

0.97

(24.64)

0.04

(1.02)

0.06

(1.52)

0.10

(2.54)

0.26

(6.60)

Notes:

1) Not to scale

2) Dimensions in inches.
(Dimensions in millimetres)

3) All dimensions are Typical except

*

where marked with an. This gap is

associated with the isolation barrier.

M Mitel (design) and ST-BUS are registered trademarks of MITEL Corporation
Mitel Semiconductor is an ISO 9001 Registered Company
Copyright 1999 MITEL Corporation
All Rights Reserved
Printed in CANADA

TECHNICAL DOCUMENTATION - NOT FOR RESALE

World Headquarters - Canada

Tel: [phone]

Fax: [phone]

North America Asia/Pacific Europe, Middle East,

Tel: [phone] Tel: [phone] and Africa (EMEA)

Fax: [phone] Fax: [phone] Tel: [phone]

Fax: [phone]

http://www.mitelsemi.com

Information relating to products and services furnished herein by Mitel Corporation or its subsidiaries (collectively “Mitel”) is believed to be reliable. However, Mitel assumes no
liability for errors that may appear in this publication, or for liability otherwise arising from the application or use of any such information, product or service or for any infringement of
patents or other intellectual property rights owned by third parties which may result from such application or use. Neither the supply of such information or purchase of product or
service conveys any license, either express or implied, under patents or other intellectual property rights owned by Mitel or licensed from third parties by Mitel, whatsoever.
Purchasers of products are also hereby notified that the use of product in certain ways or in combination with Mitel, or non-Mitel furnished goods or services may infringe patents or
other intellectual property rights owned by Mitel.

This publication is issued to provide information only and (unless agreed by Mitel in writing) may not be used, applied or reproduced for any purpose nor form part of any order or
contract nor to be regarded as a representation relating to the products or services concerned. The products, their specifications, services and other information appearing in this
publication are subject to change by Mitel without notice. No warranty or guarantee express or implied is made regarding the capability, performance or suitability of any product or
service. Information concerning possible methods of use is provided as a guide only and does not constitute any guarantee that such methods of use will be satisfactory in a specific
piece of equipment. It is the user’s responsibility to fully determine the performance and suitability of any equipment using such information and to ensure that any publication or
data used is up to date and has not been superseded. Manufacturing does not necessarily include testing of all functions or parameters. These products are not suitable for use in
any medical products whose failure to perform may result in significant injury or death to the user. All products and materials are sold and services provided subject to Mitel’s
conditions of sale which are available on request.