PTC Thermistors, Overload Protection

For Telecommunication

2322 66. 9....

Vishay BCcomponents

Document Number: 29070

For technical questions contact: nlr.europe@vishay.com

www.vishay.com

Revision: 10-Oct-03

163

FEATURES

• Wide resistance range in telecom area 4... to 70 Ω

• Fast protection against power contact faults

• Withstand high overload currents of up to 10 A

• High voltage withstanding capabilities for the larger sized

thermistors

• Good tracking over a wide temperature range for all

matched or binned types

• UL1434 approved types available (XGPU2)

• Excellent stability over extended time

• All telecom PTCs are coated with a high temperature

silicon lacquer (UL94V0) to protect them from any harsh

environments and to improve their lifetime.

APPLICATIONS

• Main Distribution Frame (MDF)

• Central Office Switching (C.O.)

• Subscriber Terminal Equipment (T.E.)

• Set-top box (S.B.).

MARKING

Clear marking on a grey coated body.

BC and R25 value.

DESCRIPTION

Advanced developments in telephony equipment in recent

years have radically altered the protection requirements for

both exchange and subscriber equipment. The Vishay

BCcomponents range of Positive Temperature Coefficient

(PTC) thermistors includes devices specially designed to

provide overcurrent protection.

CCB913

SUBSCRIBER

LOOP

INTERFACE

CIRCUIT

(SLIC)

OR

TRANSFORMER

voltage

clamp

PTC

PTC

MDF

SECONDARY

PROTECTION

PRIMARY

PROTECTION

(OPTIONAL)

subscriber

lines

+θ

PTC

+θ

+θ

+θ

Typical telephone line showing where PTC thermistors

can be used for overcurrent protection.

ELECTRICAL DATA AND ORDERING INFORMATION

Notes

1. MDF: Main Distribution Frame; C.O.: Central Office Switching; T.E.: Subscriber Terminal Equipment; S.B.: Set-top Box.

2. UL 1434 approved types.

V

MAX.

(V)

NON-TRIP

CURRENT

RESISTANCE

MATCHED

PAIRS

TRIP

CURRENT

MAX.

TRIP TIME

at 25 °°°°C

APPLICATION

COMPATIBILITY

CATALOG

NUMBER

2322 ... .....

(mA)

at T

(°°°°C)

(Ω

Ω

Ω

Ω)

TOL

(%)

(mA)

at T

(°°°°C)

(s)

(mA)

220

70

70

25

±20

1 Ω

200

25

2.5

1000

C.O.

K20/21

661 93048

230

100

70

10

±20

1 Ω

250

25

3

1000

MDF; ISDN

K20/21

661 93147

245

60

70

70

+10/−15

no

180

25

60

220

C.O.

−

661 93025

245

75

70

33

±20

±5%

150

10

1.2

1000

C.O.

−

661 93037

245

70

70

25

±15

no

200

25

20

400

C.O.

K20/21; FTCSE I31-24

661 93175

245

65

85

25

±20

2%

200

25

3.40

650

C.O.

K20/21

661 93142

245

140

55

16

±20

no

270

25

8

1000

T.E.

K20/21; FTCSE I31-21

662 93081

245

140

55

10

±20

no

270

25

8

1000

T.E.

K20/21; FTCSE I31-21

662 93074

250

100

40

20

+10/−20

1 Ω

220

25

1

1 000

MDF

−

661 93118

250

70

70

25

±20

1 Ω

175

25

1.3

1 000

MDF; C.O.

K20/21

661 93148

250

100

70

10

±20

no

450

0

0.30

8 000

T.E.

K20/21

663 93025

285

135

95

8

±25

0.5 Ω

400

25

6

1000

MDF; ISDN

K20/21

661 93078

300

100

70

16

±25

no

250

25

2.0

1000

MDF; T.E.

K20/21

661 93121

350

100

70

10

±20

no

270

25

4.0

1000

T.E.; S.B.

K20/21

661 93124

350

100

70

10

±20

1 Ω

270

25

4.0

1000

C.O.

K20/21

661 93146

600

50

70

50

±20

1 Ω

140

25

1

1000

C.O.

K20/21

661 93135

600

70

70

35

±20

3 Ω

600

0

3

1000

C.O.

K20/21

661 93056

600

70

70

25

±20

2%

170

25

4

700

C.O.

K20/21

661 93139

600

70

70

25

±20

2%

170

25

8

700

C.O.

K20/21

662 93129

600

175

25

10

±20

0.5 Ω

400

25

7

1000

C.O.

UL1459/GR1089

600

175

25

10

±20

no

400

25

7

1000

T.E.; S.B.

UL1459/GR1089