ETALDOC 500/8

Page 1 of 4

January 2001

PRODUCT DATA SHEET

ULTRA LOW DISTORTION

P3156

LOW PROFILE LINE MATCHING
TRANSFORMER

Features

Applications

∗

  Ultra Low Distortion

∗

  V.90 and V.92 modems

∗

  Low Profile (11mm)

∗

  Line matching

∗

  Extended Frequency Response

∗

  IEC 950, UL 1950 and EN 60950 certified

∗

  UL Recognized Component

∗

  BABT Certificate of Recognition

∗

  CSA NRTL/C Certificate of Compliance

∗

  Flat TX and RX Responses

∗

  High Thermal Stability

 
 

 

DESCRIPTION

P3156 is intended for data communications to V.90
and V.92 (56kbps) data rates. P3156 is specifically
designed to be matched to both 600 ohm and
complex impedance telephone lines, using a
minimum of external components, with very flat TX
and RX frequency responses.

P3156 has extended flat frequency response from
30Hz to 4kHz with very low levels of signal distortion
at signal frequencies as low as 150Hz.

P3156 also exhibits stable characteristics over its
operating temperature range to  maximize data
throughput under varying environmental
conditions without the need for modem retraining.

P3156 is certified to IEC 950, EN 60950,
EN 41003 and UL1950. P3156 is a UL
Recognized Component and is supported by a
BABT Certificate of Recognition, a  CSA Certificate
of Compliance and an IEC CB Test Certificate.

E203175

to Electronic Techniques

(Anglia) Limited

P3156

ETALDOC 500/8

Page 2 of 4

January 2001

SPECIFICATIONS

Electrical

At T = 25ºC and as circuit Fig. 2 unless otherwise stated.

Parameter

Conditions

Min

Typ

Max

Units

Insertion Loss

f = 2kHz, R

L

 = 510

Ω

-

4.8

-

dB

Frequency Response

LF -3dB cutoff
HF -3dB cutoff
100Hz - 4kHz

-
-
-

10

8

-

-
-

±0.2

Hz

kHz

dB

Return Loss

200Hz - 4kHz

14

-

-

dB

Distortion 

(1)

0dBm in line, 3rd Harmonic
f = 600Hz
-3dBm in line, 3rd Harmonic
f = 150Hz

-

-

-

-77

-90

-

dBm

dBm

Balance

DC - 5kHz

80

-

-

dB

Saturation

Excitation 50Hz
250Vrms.
Output voltage
across line

-
-

-
-

10
65

Vrms

Vpeak

Voltage
isolation

(2)

50Hz
DC

3.88

5.5

-
-

-
-

kVrms

kV

Operating range:
Functional
Storage
Humidity

Ambient temperature

-10
-40

-

-
-
-

+70

+125

95

ºC
ºC

%R.H.

Lumped equivalent circuit parameters as Fig. 1

DC resistance, R

DC

(3)

Sum of windings

-

280

-

Ω

Leakage inductance 

∆

L

-

20

-

mH

Shunt inductance Lp

(4)

-43dBm 200Hz

-

14

-

H

Shunt loss Rp

(4)

-43dBm 200Hz

12

-

-

k

Ω

Notes
1.

Third harmonic typically exceeds other
harmonics by 10dB.

2.

Components are 100% tested at 6.5kV DC.

3.

Caution:  do not pass DC through windings.
Telephone line current, etc. must be diverted
using semiconductor line hold circuit.

4.

At signal levels greater than -20dBm,  Lp will
increase and  Rp will decrease slightly but the
effect is usually favourable to the return loss
characteristic.

Equivalent Circuit

IDEAL

1:1

LINE

MODEM

Fig 1

P3156

ETALDOC 500/8

Page 3 of 4

January 2001

MATCHING RECOMMENDATIONS

In practice the 360

Ω

 load resistor in figure 2 will

connect to a low output impedance TX driver.   The
33nF capacitor on the load side should appear in
parallel with the 360

Ω

 resistor (rather than in

parallel with the transformer winding) to obtain flat
TX response to line.

Figure 3 gives flat RX and TX responses against
the complex reference impedance (typically ±0.5dB
30Hz - 4kHz) with return loss better than 15dB.

In practice, the 750

Ω

 load resistor will connect to

a low output impedance TX driver.    The 120nF
capacitor, which should have a temperature stable
dielectric, should appear in parallel with the 750

Ω

resistor (rather than in parallel with the
transformer winding) to obtain flat TX response to
line.

For recommended matching to other reference
impedances please contact Profec Technologies.

CONSTRUCTION

Dimensions shown are in millimetres (inches).
Geometric centres of outline and pin grid coincide within a tolerance circle of 0.6mmØ.
Windings may be used interchangeably as primary or secondary.

Recommended Circuit

Fig 2

360

LINE

600

33nF

33nF

µ

2 2   F

600    MATCH

Ω

EUROPEAN CTR21 COMPLEX MATCH

Recommended Circuit

Fig 3

750

LINE

270

750

120nF

68nF

150nF

µ

2 2   F

P3156

ETALDOC 500/8

Page 4 of 4

January 2001

SAFETY

CERTIFICATION

Constructed in accordance with IEC 950:1991,
EN60950:1992 (BS7002:1992) to amendment 5,
supplementary insulation, and UL 1950 3rd Edition,
reinforced insulation, 250Vrms  maximum working
voltage, flammability class V-0.
Distances through solid insulation 0.4mm
minimum.

Certified under the IEC CB scheme (Certificate
GB443W) to IEC 950:1991, up to amendment 4, sub-
clauses 2.2.2, 2.9.1, 2.9.6, 2.9.7, 4.4.3 (class V-0) and
5.3 for a maximum working voltage of 250Vrms,
nominal mains supply voltage not exceeding
300Vrms and a maximum  operating  temperature  of
70ºC  in  Pollution Degree 2 environments,
supplementary insulation.
Recognized under the Component Recognition
Program of Underwriters Laboratories Inc. to US and
Canadian requirements CAN/CSA C22.2
No. 950-95/UL1950, Third Edition, including revisions
through to revision date March 1, 1998, based on
Fourth Amendment of IEC 950, Second Edition,
maximum working voltage 250Vrms, Pollution Degree
2, reinforced insulation.

UL File number E203175.
CSA Certificate of Compliance 1107696 (Master
Contract 188107).
Approved and certified by BABT to EN 60950 and
EN 41003.
BABT Certificate of Recognition CR/0137.

Additionally, Profec Technologies certifies all
transformers as providing voltage isolation of
3.88kVrms, 5.5kV DC minimum.   All shipments are
supported by a Certificate of Conformity to current
applicable safety standards.

ABSOLUTE MAXIMUM RATINGS

COPYRIGHT

(Ratings of components independent of circuit).

Short term isolation voltage (2s)

4.6 kVrms,
6.5 kVDC

DC current

100

µ

A

Storage temperature

-40ºC to
+125ºC

Lead temperature, 10s

260ºC

ETAL and P3156 are  Trade Marks of Profec
Technologies Ltd.
The  Trade Mark ETAL is registered at the UK
Trade Marks Registry.

Profec Technologies Ltd. is the owner of the
design right under the Copyright Designs and
Patents Act 1988 and no rights or licences are
hereby granted or implied to any third party.

© 1997-2000 Profec Technologies Ltd.
Reproduction prohibited.

T R A N S F O R M I N G    T H E         F U T U R E

Profec Technologies Ltd., 10 Betts Avenue, Martlesham Heath, Ipswich, IP5 3RH, England

                           Telephone: +44 (0) 1473 611422

Fax:  +44 (0) 1473 611919

Websites: www.etal.ltd.uk

www.profec.com

Email:

info@etal.ltd.uk

sales@profec.com

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