PTC thermistors for
telecom
Telecom Pair Protector (TPP)
Series/Type:
B598**/ B597**
Date:
March 2006
EPCOS AG 2006. Reproduction, publication and dissemination of this publication, enclosures hereto and the
information contained therein without EPCOS' prior express consent is prohibited.
Applications
Overcurrent protection for telecom applications
Suitable for line card applications e.g. POTS, access networks, customer premises equipment
(CPE) or intergated voice data (IVD)
Features
Two resistance matched PTCs in a plastic housing
Compliant with ITU-T standards
basic level lightning surges (10/700 s)
basic level power induction (600 V, 1 A, 0.2 s)
power contact criteria A/B (230 V, 15 min.)
Suitable for continuous connection to mains voltages of 110/230 VAC
in tripped (high ohmic) condition
Matching with narrow resistance tolerance
Housing material according to UL94-V0
Marked with manufacturer's logo, type designation and date code
RoHS-compatible
Options
Alternative tolerances and resistances on request
Delivery mode
Blister tape, 380-mm reel with 24-mm tape, taping to IEC 60286-3
General technical data
Max. operating voltage
V
max
245
VAC
Operating temperature range
(V = 0)
T
op
20/+125
C
Operating temperature range
(V = 230 V)
T
op
0/+70
C
Insulating test voltage between PTC1 and PTC2
V
ins
>3
kV
Resistance matching in one housing
R
2
R
1
<1.0
Electrical specifications and ordering codes
Type
R
R
R
R
%
I
R
@ 25
C
mA
I
R
@ 70
C
mA
I
S
@ 25
C
mA
I
Smax
@ 230 VAC
A
Ordering code
T1735
35
+15/ 20
110
70
230
4.6
B59735T1120A062
T1750
50
15
90
60
190
2.5
B59750T1120A062
T1810
10
20
180
120
360
1.0
B59810T1120A062
T1825
25
20
130
85
260
2.8
B59825T1120A062
T1835
35
+15/ 20
110
70
230
4.6
B59835T1120A062
T1850
50
15
90
60
190
2.5
B59850T1120A062
Telecom
Telecom pair protector - TPP (SMD)
T1735 ... T1850
Page 2 of 6
Please read Important notes and
Cautions and warnings at the end of this document.
Switching times and ordering codes
Type
t
S (typ)
@ I
Smax
,
230 VAC
s
t
S (typ)
@ 1 A,
230 VAC
s
t
S (typ)
@ 500 mA,
230 VAC
s
Ordering code
T1735
0.04
0.8
3.4
B59735T1120A062
T1750
0.1
0.6
2.4
B59750T1120A062
T1810
3.8
3.8
19.0
B59810T1120A062
T1825
0.2
1.5
6.5
B59825T1120A062
T1835
0.06
1.1
4.5
B59835T1120A062
T1850
0.13
0.8
3.1
B59850T1120A062
Dimensional drawings
Solder pad
Dimensions in mm
Type
l
max
w
max
h
max
T1735
11.0
9.0
10.5
T1750
11.0
9.0
10.5
T1810
11.0
9.0
11.5
T1825
11.0
9.0
11.5
T1835
11.0
9.0
11.5
T1850
11.0
9.0
11.5
Telecom
Telecom pair protector - TPP (SMD)
T1735 ... T1850
Page 3 of 6
Please read Important notes and
Cautions and warnings at the end of this document.
Cautions and warnings
General
EPCOS thermistors are designed for specific applications and should not be used for purposes
not identified in our specifications, application notes and data books unless otherwise agreed
with EPCOS during the design-in-phase.
Ensure suitability of thermistor through reliability testing during the design-in phase. The
thermistors should be evaluated taking into consideration worst-case conditions.
Storage
Store thermistors only in original packaging. Do not open the package before storage.
Storage conditions in original packaging: storage temperature
25
C ... +45
C, relative
humidity
75% annual mean, maximum 95%, dew precipitation is inadmissible.
Avoid contamination of thermistors surface during storage, handling and processing.
Avoid storage of thermistor in harmful environment with effect on function on long-term
operation (examples given under operation precautions).
Use thermistor within 6 months after delivery.
Handling
PTCs must not be dropped. Chip-offs must not be caused during handling of PTCs.
Components must not be touched with bare hands. Gloves are recommended.
Avoid contamination of thermistor surface during handling.
Soldering
Use rosin-type flux or non-activated flux.
Insufficient preheating may cause ceramic cracks.
Rapid cooling by dipping in solvent is not recommended.
Complete removal of flux is recommended.
Mounting
Electrode must not be scratched before/during/after the mounting process.
Contacts and housing used for assembly with thermistor have to be clean before mounting.
Especially grease or oil must be removed.
When PTC thermistors are encapsulated with sealing material, the precautions given in chapter
"Mounting instructions", "Sealing and potting" must be observed.
When the thermistor is mounted, there must not be any foreign body between the electrode of
the thermistor and the clamping contact.
The minimum force of the clamping contacts pressing against the PTC must be 10 N.
During operation, the thermistor's surface temperature can be very high. Ensure that adjacent
components are placed at a sufficient distance from the thermistor to allow for proper cooling at
the thermistors.
Ensure that adjacent materials are designed for operation at temperatures comparable to the
surface temperature of thermistor. Be sure that surrounding parts and materials can withstand
this temperature.
Avoid contamination of thermistor surface during processing.
Telecom
Telecom pair protector - TPP (SMD)
T1735 ... T1850
Page 4 of 6
Please read Important notes and
Cautions and warnings at the end of this document.
Operation
Use thermistors only within the specified temperature operating range.
Use thermistors only within the specified voltage and current ranges.
Environmental conditions must not harm the thermistors. Use thermistors only in normal
atmospheric conditions. Avoid use in deoxidizing gases (chlorine gas, hydrogen sulfide gas,
ammonia gas, sulfuric acid gas etc), corrosive agents, humid or salty conditions.Contact with
any liquids and solvents should be prevented.
Be sure to provide an appropriate fail-safe function to prevent secondary product damage
caused by abnormal function (e.g. use VDR for limitation of overvoltage condition).
Telecom
Telecom pair protector - TPP (SMD)
T1735 ... T1850
Page 5 of 6
Please read Important notes and
Cautions and warnings at the end of this document.
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