ETALDOC 710/6

Page 1 of 4

January 2001

PRODUCT DATA SHEET

LOW COST, LINE MATCHING TRANSFORMER

P3800

Features

Applications

∗

  Low Cost

∗

  V.32bis and V.22bis modems

∗

  12.6mm (0.5") seated height

∗

  Fax

∗

  Industry Standard Pinout

∗

  Line Matching

∗

  IEC 950, UL 1950 and EN 60950 Certified

∗

  Voice

∗

  UL Recognized Component

∗

  BABT Certificate of Recognition

∗

  High thermal stability

∗

  Directly replaces 9000, 671-8236,

MTLM 1200, EMIT-1200 and ATS-079/A

 
 

 

DESCRIPTION

P3800 is intended for low-cost, medium-speed data
and voice applications. It is a direct substitute for
industry standard P1200, being  mechanically
compatible and having identical signal/distortion
and matching characteristics, and suitable for
supplementary insulation, 250V working.

P3800 also directly replaces 9000, 671-8236,
MTLM1200, EMIT-1200 and ATS-079/A without
changes to matching components, but with the
added benefit of considerably improved thermal
stability.

P3800 uses patented design and construction
methods to achieve excellent signal performance
and safety isolation to international standards at
truly low cost.   P3800 is certified to EN 60950,
IEC 950, UL1950 and EN 41003. P3800 is a UL
Recognized Component and is supported by a
BABT Certificate of Recognition and an IEC CB
Test Certificate.

Patented

E203175

to Electronic Techniques

(Anglia) Limited

P3800

ETALDOC 710/6

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

 = 560

Ω

-

-

1.5

dB

Frequency response

200Hz - 4kHz

-

-

±0.2

dB

Return Loss

200Hz - 4kHz

18

-

-

dB

Third Harmonic
Distortion 

(1)

450Hz   0dBm

-

-72

-60

dBm

Voltage
isolation 

(2)

50Hz
DC

2.12

3.0

-
-

-
-

kVrms

kV

Operating range:
Functional
Storage

Ambient temperature

0

-40

-
-

+70
+85

ºC
ºC

Lumped equivalent circuit parameters as Fig. 1

DC resistance, R

DC

 

(3)

Sum of windings

120

-

148

Ω

Leakage inductance 

∆

L

14.5

-

18

mH

Shunt inductance Lp 

(4)

-43dBm 200Hz

2.8

-

-

H

Shunt loss Rp 

(4)

-43dBm 200Hz

5

-

-

k

Ω

 

Notes

1.  Third harmonic typically exceeds other

harmonics by 20dB.

2.  Components are 100% tested at 3.25kV DC.
3.  Caution:  do not pass DC through windings.

Telephone line current, etc. must be diverted
using choke or 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

Fig. 1

IDEAL

1:1

½   L

½   L

½ R

½ R

Patented

P3800

ETALDOC 710/6

Page 3 of 4

January 2001

MATCHING RECOMMENDATIONS

CONSTRUCTION

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

Recommended Circuit

Fig. 2

560

LINE

600

* If return loss >16dB, 300Hz - 4kHz is acceptable, blocking
  capacitor may be relaxed to 4.7 F

33nF

27nF

5%

+

_

2%

+

_

µ

*

+50%

20%

_

µ

6.8 F

+50%

20%

_

5%

+

_

600    MATCH

Ω

Figure 3 gives flat RX and TX responses against the 
CTR21 complex reference impedance (typically 
around  ±0.5dB 300Hz - 3.4kHz).  Return loss is 
typically better than 20dB.   The circuit values in 
parentheses give optimum flatness at a small 
sacrifice in return loss.

For circuits with existing board drillings, figure 4 
gives good return loss (>20dB) and RX flatness 
against the CTR21 complex reference impedance, 
but TX flatness is degraded by the use of this 
topology.

EUROPEAN CTR21 COMPLEX MATCH

Recommended Circuit

Fig. 3

150

(220)

LINE

270

750

750

(680)

56nF

(150nF)

100nF

150nF

µ

2.2 F

Fig. 4

820

LINE

270

750

330

27nF

68nF

150nF

µ

2.2 F

Connections

Dimensions

P3800

ETALDOC 710/6

Page 4 of 4

January 2001

SAFETY

ABSOLUTE MAXIMUM RATINGS

(Ratings of components independent of circuit).

Constructed in accordance with IEC 950:1991,
EN60950:1992 (BS7002:1992), supplementary
insulation, 250Vrms maximum working voltage,
flammability class V-0.

There are no special installation requirements
(beyond attending to usual PCB track
separations) since the integral cover provides
supplementary insulation from its external faces
to internal core and windings.

Short term isolation voltage (1s)

DC current
Storage temperature

Lead temperature, 10s

2.12kVrms
3.0kVDC
100

µ

A

-40ºC to
+85ºC

260ºC

CERTIFICATION

COPYRIGHT

Certified under the IEC CB scheme (Certificate
GB445W) to IEC 950:1991, up to amendment 4,
sub-clauses 1.5, 1.5.1, 1.5.3, 2.2, 2.2.3, 2.2.4, 2.9.2,
2.9.3, 2.9.4, 4.4, 4.4.3.2 (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.

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, supplementary insulation.

UL File number E203175.
Approved and certified by BABT to EN 60950 and
EN 41003.
BABT Certificate of Recognition 608755

Additionally, Profec Technologies certifies all
transformers as providing voltage isolation of
2.12kVrms, 3kV DC minimum.  All shipments are
supported by a certificate of conformity to current
applicable safety standards.

ETAL, P1200, and P3800 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.

P3800 design and construction are protected by
patents and registered design.
British Patent No. 2340667.
UK Registered Design No. 2077360.
French Registered Design No. 991512.
Germany Registered Design 49902311.0.
United States Registered Design 426, 815.
Other patents and registered designs pending.

© 1998 – 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

Patented

ISO 9001

FM 25326