T604.F (05/12)1pulseelectronics.com
ISDN S-Interface Transformers
Meets pulse waveform template of CCITT I.430 when
recommended transformer and chip pair are used
Excellent longitudinal balance
2kVrms isolation voltage
Available in tape and reel, tray or tube packaging
Recognized by UL
SC-1
Mechanical Schematic
USA 858 674 8100 Germany 49 7032 7806 0 Singapore 65 6287 8998 Shanghai 86 21 62787060 China 86 755 33966678 Taiwan 886 3 4356768
Electrical Specifications @ 25°C - Operating Temperature 0°C to +70°C
Part
Number
Ratio
(±2%)
OCL Pri
(mH MIN)
L Sec
(μH MAX)
Cw/w
(pF MAX)
CD Pri
(pF MAX)
DCR Pri
(Ω ±25%)
DCR Sec
(Ω ±25%) IDC
(mA MAX)
Package /
SchematicA B A & B A B A & B A B A B A B
PE-65793 1:1 1:1 22 5 5 100 42 42 2.4 2.4 2.4 2.4 1SC-1
PE-65795 1:2 1:2 22 15 15 100 80 80 4.3 4.3 4.3 4.3 1SC-1
Dimensions:
Unless otherwise specified,
all tolerances are ±
Inches
mm
.010
0,25
C
∆
L
Surface Mount, Dual, 2000 Vrms
8
916
PE-6579X
Date Code
Country of Origin
.530 MAX
13,46
.720 MAX
18,29
.600
15,24
16X .030
0,76
.120 TYP
3,05
.050
TYP
1,27
.520
13,21
.760
19,30
.100 TYP
2,54 .700
17,78
.004/0,10
16 SURFACES
.010/.020
0,25/0,51
.122
3,10
.950 MAX
24,13
.100
2,54
.390 MAX
9,91
.040/.050
1,02/1,27
SUGGESTED PAD LAYOUT
16 13
1423
15 14 12 9
58
67
11 10
PRI
COIL ACOIL B
SEC
T604.F (05/12)2pulseelectronics.com
ISDN S-Interface Transformers
Meets pulse waveform template of CCITT I.430 when
recommended transformer and chip pair are used
Excellent longitudinal balance
2kVrms isolation voltage
Recognized by UL
IS-1
ID-1
Mechanical
Mechanical
Schematic
Schematic
Electrical Specifications @ 25°C - Operating Temperature 0°C to +70°C
Part
Number
Ratio
(±2%)
OCL Pri
(mH MIN)
L Sec
(μH MAX)
Cw/w
(pF MAX)
CD Pri
(pF MAX)
DCR Pri
(Ω ±25%)
DCR Sec
(Ω ±25%)
Isolation
(VRMS MIN)
IDC
(mA MAX)
Package /
Schematic
PE-64995NL 1CT:2CT 22 15 100 80 2.5 4.3 2000 1 SC-1
CC
A A
∆
2kV Isolation, Through Hole, Single Transformers
Electrical Specifications @ 25°C - Operating Temperature -40°C to +125°C
Part
Number
Turns Ratio DCR (mΩ MAX)
Package /
Schematic
Equivalent
Single
Primary
Pins
Secondary
Pins
Equivalent
Single
Primary
Pins
Secondary
Pins
PE-65495NL 1:2 1-4 1-4 16-13 1:2 PE-64995NL 5-8 12-9 ID-1
Ratio Ratio
L
Through Hole, Single & Dual, 2000 Vrms
.558 MAX
14,20
1
2
3
6
4
PE-6499X
DATE CODE
.120 – .020
3,10 0,30
.400
10,20
.400
10,20
C
L
C
L
LEADS ARE 22 AWG SOLDERABLE
5 .558 MAX
14,20
.400 MAX
10,20
6
4
1
3
25
PRI : SEC
PRI
SEC
16 13
1423
15 14 12 9
58
67
1110
COIL A COIL B
T604.F (05/12)3pulseelectronics.com
ISDN S-Interface Transformers
Transformer Selection & Packaging
IC
Manufacturer
IC
Part Number
Dual
Surface Mount
Single
Through Hole, 2 kVRMS
Dual
Through Hole
TX & RX TX RX TX & RX
AT&T/Lucent T7903 PE-65795 PE-64995NL PE-64995NL PE-65495
Mietec MTC-2072 PE-65795 PE-64995NL PE-64995NL PE-65495
Mitel MT8930 PE-65795 PE-64995NL PE-64995NL PE-65495
MC145474/145475
MC145574
National TP3420/34221 PE-65795 PE-64995NL PE-64995NL PE-65495
SGS Thomson ST5420, ST5421 PE-65795 PE-64995NL PE-64995NL PE-65495
PEB 2080/2081/2085
Siemens PSB 2186 PE-65795 PE-64995NL PE-64995NL PE-65495
PEB 2084/2086
Yamaha 7405B PE-65795 PE-64995NL PE-64995NL PE-65495
Notes:
A. In this catalog, turns ratio is expressed as
“primary:secondary”. The term “CT” designates a
center tapped winding. A center tapped winding
can be created by connecting two ends of a split
center winding together on the printed circuit board. In
ISDN-S applications, the primary winding is the line
side transformer winding.
B. The minimum primary inductance and the maximum
distributed capacitance satisfy the transmistter
output and receiver input impedance requirements of
CCITTI I.430 for both the TE and the NT. The maximum
distributed capacitance allows sucient margin for the
capacitance of the IC and a protection diode network.
It is consistent with the overall maximum value
specified and the permitted length of the basic access
TE cord.
C. The maximum specified unbalanced DC current
capability is based on 20 mH minimum primary OCL
D. National recommends a 1:2 receive transformer, but
used as a 1:1 ratio by connectin only half the secondary
winding. See National’s application note.
E. PE-65950 and PE-65853 are recommended for use
with Siemens PEB 2080/2085 and help in meeting the
required longitudinal balance.
F. Standard packaging for all chokes and transformers
listed in this catalog is anti-static tubes. Optional
anti-static tray packaging can be ordered for the
surface mount SC-1 and LA-1 packages by adding an
“R” sux to the part number, (ie: PE-65795R). Optional
tape and reel packaging can be ordered for all surface
mount packages by adding a “T” sux to the part
number, (ie: PE-65795T).
G. For PE-65854, OCL at -40C is 27 H minimum. For
maximum performance, using windings (1-8) and (2-7)
as a pair and windings (3-6) and (4-5) as a pair.
H. For transformers and choke modules, refer to data
sheet T632.
PE-65795 --PE-65495
Packaging Information
Package Type Part Weight Parts/Tube Parts/Tray Parts/Reel Reel Diameter Tape Width Pitch
LA-1 SMT 2.0 Grams 30 60 250 13 Inches 24 mm 24 mm
SC-1 SMT 7.0 Grams 20 50 150 13 Inches 44 mm 24 mm
ID-1 THT 7.0 Grams 20 - - - - -
IS-1 THT 4.0 Grams 35 - - - - -
F
D
Motorola
T604.F (05/12)4pulseelectronics.com
ISDN S-Interface Transformers
Surface Mount, Dual, 2000Vrms
1. General Information - The S-interface is the
standardized four-wire digital telephone access point
defined by the CCITTI I-series recommendations for
the Integrated Services Digital Network. This “basic
rate access” accommodates two 64Kpbs “B-channels”
for information, one 16Kbps “D-channel” intended
for signaling and control, and 48 Kbps for framing
and other purposes, giving a total rate of 192Kbps. The
CCITT physical layer recommends that the user network
interface be transformer coupled. A typical application
circuit is presented in Figure 1.
The transformer provides isolation for the line card
or the terminal from the line. It is also a way to provide
phantom power feeding to the terminal over the S-loop.
Each end requires a transmit and a receive transformer.
Chokes are used in some applications to reduce
common mode noise (see note 5).
The transformers described in this data sheet are
matched to the transceivers oered by the major IC
manufacturers listed. The use of a transformer-chip pair
assures that all requirements of CCITT I.430 are met
with respect to pulse waveform templates, impedance
and longitudinal balance. In addition, the transformers
provide the isolation voltages required by the regulatory
agencies and are capable of passing surge voltage tests.
2. Longitudinal Balance for Transformers - The
longitudinal conversion loss specification in I.430 includes
a test setup that is intended for system evaluation,
whether TE or NT. Such a test is performed with DC
current present. The transformer plays an essential role
in achieving the required balance. However, all other
elements in the circuit should be also designed to provide
the highest possible symmetry. These elements include
the protection circuitry, series resistors, chip transmitter
output and receiver input, as well as the cables used
and the TE cord where applicable. A high level of
transformer balance compensates for some circuit AC-
unbalance, and assures compliances of the system with
I.430 on longitudinal conversion loss (LCL) and signal
balance. This is accomplished by a well AC-balanced
winding configuration whereby the capacitive coupling
between primary and secondary windings is evenly
distributed. Also, both halves of the lineside winding are
well balanced. The transformers meet the following LCL
specifications:
•10kHzto300kHz:60dBminimum
•300kHzto1MHz:Minimumvaluedecreasing
20dB/decade.
(continued on next page)
IC
XMIT
Sec : Pri
RCV
High
Freq
Choke
IC
RCV
XMIT
Low
Freq
Choke
Low
Freq
Choke
High
Freq
Choke
S-INTERFACE
Local
Power
DC
Supply
Pri : Sec
NTTE
Sec : Pri Pri : Sec
Figure 1. Typical ISDN S-Interface Application Circuit
T604.F (05/12)5pulseelectronics.com
ISDN S-Interface Transformers
2. (continued from previous page) A recommended
test set up is shown in Figure 2. A high inductance “low
frequency” is common mode choke, such as PE-
65950NL or PE-65853NL, is recommended to improve
balance, or to correct inherent unbalances of some
circuits.
3. Impedance Requirements - The requirements for
minimum impedance in the inactive and powered-
down states are expressed by impedance templates
for both transmitter and receiver in NT and TE. At the
lowfrequencyendof1MHz,itisreasonableto
assume that the impedance seen from the line is
entirely capacitive. The maximum capacitance budget,
derived from the templates, is somewat dierent
for the NT and the TE. Contributors to the total
capacitance are: the chip output, the protection circuit,
the transformer, common mode choke, and any other
element that may be present. In the TE case, there is
also the maximum allowable TE cord impedance. Here
the maximum buget is 800pF. As a rule, the
capacitances should be kept as low as possible in the
interface circuit design. With the specified transformer
capacitances, it is possible to remain within budget
and have a reasonable margin for measurement errors.
4. Common Mode Chokes - The “high frequency” 4-wire
common mode chokes shown on pages 7 and 8
provide an eective means of compliance with national
andinternationalregulationsonEMI.Theyaredesigned
to be used in conjunction with either Pulse’s ISDN
S-Interface or T1/CEPT transformers as shown in Figure
1. A high inductance “low frequency” common mode
choke is recommended to improve balance, or to
correct inherent unbalances of some ISDN S-Interface
circuits.
5. Surge Voltage Capability for Transformers and
Chokes
•LongitudinalVoltagePeak:2,400V10/700μsec
•MetallicVoltagePeak:800V10/560μsec
6. Behavior Under Fault Conditions - Telephony voltages
may accidentally appear on the ISDN S-Interface line
to the transformer. The transformer will withstand a
DC current of 0.5 Amps for 15 minues without
permanent damage. Such current may be cauased by
the telephone central battery. The transformer will
also survive ringing voltages. These are nominally
120Vor200Vmaximumat20to60Hz,limitedby
1500W resistive or 400 to 600W inductive limiting.
These may cause peak currents.
7. Flammability-Materialsusedintheproductsare
recognizedUL94-VO.Productsmeettherequirements
of IEC 695-2-2 (Needle Flame Test).
Surface Mount, Dual, 2000Vrms
Out
HP-8751A
Network Analyzer
RBA
VT
EL
ISM-1
Pri Sec
Terminating
Resistor
ISM-1 = Wandel and Goltermann
Signal Balance Ratio Bridge
Figure 2. Longitudinal Balance Test Circuit
T604.F (05/12)6pulseelectronics.com
ISDN S-Interface Transformers
Designed for 4-wire links, ISDN-S/T and T1/E1/CEPT
High frequency chokes for EMI reduction
Low frequency chokes improve longitudinal balance in
ISDN-S/T links
Surface mount and through hole models available
Electrical Specifications @ 25°C - Operating Temperature 0°C to +70°C
Part
Number
OCL Pri
(mH MIN)
L Sec
(μH MAX)
Cw/w
(pF MAX)
DCR
(W MAX)
Isolation
(VRMS MIN)
Package /
Schematic
PE-65853NL 4.7 mH ±30% 1 60 1.20 500 PA-2/5C (Surface Mount)
PE-65950NL 4.7 mH ±30% 1 50 1.00 500 IS-4/1C (Through Hole)
PE-65554NL 24.0 μH MIN .20 15 0.30 500 IN-1/C (Through Hole)
PE-65854NL 47.0 μH MIN .18 20 0.40 50 SH-4/C (Surface Mount)
PE-65857NL 22.5 μH MIN .23 17 0.30 500 LA-1/C (Surface Mount)
E
E
F
L
Low Frequency
High Frequency
Common Mode Chokes for Telecom Applications
0
-5
-10
-15
-20
-25
-30
Attenuation (dB)
1 MHz 10 MHz 100 MHz
Frequency
PE-65854
PE-65554/65857
3.0K
2.8K
2.6K
2.4K
2.2K
2.0K
1.8K
1.6K
1.4K
1.2K
1K
800
600
400
200
0
Impedance (Ω)
1 MHz 10 MHz 100 MHz
Frequency
PE-65554/65857
PE-65854
Typical common
mode attenuation
for high frequency
common mode
chokes based on
a 100 system.
Typical impedance
for high frequency
common mode
chokes based on
a 100 system.
20K
18K
16K
14K
12K
10K
8K
6K
4K
2K
0
Impedance (Ω)
100 KHz1 MHz 10 MHz
Frequency
PE-65950/65853
PE-65541
Typical common
mode attenuation
for low frequency
common mode
chokes based on
a 100 system.
Typical impedance
for low frequency
common mode
chokes based on
a 100 system.
7pulseelectronics.com
ISDN S-Interface Transformers
Common Mode Chokes for Telecom Applications
T604.F (05/12)
For More Information
Pulse Worldwide
Headquarters
12220 World Trade Drive
San Diego, CA
92128
U.S.A.
Tel: 858 674 8100
Fax: 858 674 8262
Pulse Europe
Einsteinstrasse 1
D-71083 Herren-
berg
Germany
Tel: 49 7032 78060
Fax: 49 7032 7806 135
Pulse China Headquarters
B402, Shenzhen Academy of
Aerospace Technol-
ogy Bldg.
10th Kejinan Road
High-Tech Zone
Nanshan District
Shenzen, PR China
518057
Tel: 86 755 33966678
Fax: 86 755 33966700
Pulse North China
Room 2704/2705
Super Ocean Finance
Ctr.
2067 Yan An Road
West
Shanghai 200336
China
Tel: 86 21 62787060
Fax: 86 2162786973
Pulse South Asia
135 Joo Seng Road
#03-02
PM Industrial Bldg.
Singapore 368363
Tel: 65 6287 8998
Fax: 65 6287 8998
Pulse North Asia
3F, No. 198
Zhongyuan Road
Zhongli City
Taoyuan County 320
Taiwan R. O. C.
Tel: 886 3 4356768
Fax: 886 3 4356823 (Pulse)
Fax: 886 3 4356820 (FRE)
Performance warranty of products oered on this data sheet is limited to the parameters specified. Data is subject to change without notice. Other brand and product names mentioned herein may be
trademarks or registered trademarks of their respective owners. © Copyright, 2012. Pulse Electronics, Inc. All rights reserved.
IN-1
IN-4
IN-1
SH-4
PA-2
Mechanicals
Schematics
8765
1234
PE-XXXXX
Date Code
Country of Origin
.595 MAX
15,11
.480 MAX
12,20
.130 – .010
3,30 – 0,25
.300
7,62
.100
2,54
C
L
C
L
.300
7,62
MAX
1
8
2
7
3
6
4
5
C
1
2
3
4
5
6
7
8
1C
1. Dimensions: Unless otherwise specified, all tolerances are ±
2. See page 3 for packaging information.
Inches
mm
.010
0,25
