
56kBit Modem Transformers
OXFORD ELECTRICAL PRODUCTS
15-17 Industrial Estate, Wroslyn Road, Freeland, Witney, Oxfordshire, OX8 8HZ England Tel: +44 (0) 1993 883214 Fax: +44 (0) 1993 882500
2/96
Type No.
Size (mm)
Return
Loss (dB)
200-4kHz
Insertion
Loss (dB)
@1kHz
Frequency
Response
(dB)
Harmonic Distortion
400Hz
(dB) typical
600Hz
(dB) typical
Isolation
Volts
RMS
Leakage
Induct.
(mH)
BABT
Approved
Number
Z1656
Z1656/4
Z1612E
Z1256
>20
>20
>20
>26
0.80
0.80
1.50
1.25
100-4kHz
+/- 0.1dB
100-4kHz
+/- 0.1dB
200-4kHz
+/- 0.1dB
50-5kHz
+/- 0.07dB
-100
-88
-83
-84
-93
-91
-93
-93
3750
3750
3750
3750
19
2.8
19.4
14.4
CR/0125
CR/0126
CR/0128
CR/0127
18x18x13
encapsulated
18x18x13
encapsulated
18x18x13
encapsulated
19x15x11.2
encapsulated
PC3456
23x16x4.5
including pins
>31
4.00
100-5kHz
+/- 0.05dB
-97
-104
1500
1.3
Pending
PC Card (SMD) Version
Through Hole Versions
Characteristics
General
The advent of high-speed 56kBit modems has necessitated
the design of Line Isolation Transformers that are capable of
providing extremely low distortion across a wide frequency range.
OEP offers the user a number of different variants, with industry
standard pin outs, from which to select a device to satisfy
particular technical and commercial considerations.
Construction
With the exception of the SMD PC Card device, P/N PC3456
these transformers are designed for conventional PCB mounting.
The epoxy resin encapsulation provides reinforced insulation to
meet the requirements of EN60950 / EN41003 and BABT
approvals. Double section bobbins are used except for the
Z1656/4 and PC3456 versions which are concentrically wound on
single section bobbins for closer coupling of the windings thus
providing extremely low leakage inductance figures.