PTC thermistors for telecom
Leadless disks,
round and square disks
Series/Type:
B59***
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 MDF applications e.g. connectors etc.
Features
Designed for combined usage of PTC and primary protection (e.g. gas arrester)
Suitable for continuous connection to mains voltages of 110/230 VAC
in tripped (high ohmic) condition
Matching available with narrow resistance tolerance
RoHS-compatible
Options
Alternative tolerances and resistances on request
Delivery mode
Round disks: packed in blister trays
Square disks: bulk
General electrical 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
Electrical specifications and ordering codes
1)
Type
R
R
R
R
%
R
25,match
I
R
@
25
C
mA
I
R
@
70
C
mA
I
S
@
25
C
mA
I
Smax
@
230 VAC
A
t
S (typ)
@ I
Smax,
230 VAC
s
Ordering code
1)
Variation of current and switching time with heat dissipation of mounting facility must be taken into account.
Round disks, contacts for clamp connection
A94
4.1
10
0.2
170
70
300
0.8
7.6
B59094A0080B110
A48
6
10
0.2
140
60
250
3.0
0.5
B59048A0080B110
A95
9.3
10
0.2
110
50
250
0.5
12
B59095A0080B110
A34
10
15
No
140
95
300
1.0
2.0
B59034A0120B010
A12
12
15
0.25
90
40
200
1.5
0.4
B59012A0080B110
Round disks, contacts for solder connection
A1037
10
15
No
140
95
300
1.0
2.0
B59037A1120B010
A1037
10
15
0.5
140
95
300
1.0
2.0
B59037A1120B110
A1042
10
15
0.5
150
100
300
1.0
4.0
B59042A1120B110
A1610
10
20
0.1
150
100
350
10.0
0.06
B59610A1120B110
A1041
25
15
0.5
100
65
200
2.8
0.2
B
59041A1120B110
A1044
35
15
0.5
90
55
180
2.8
1.15
B59044A1120B110
Square disks, contacts for solder / clamp connection
R212
12
15
No
120
50
300
1.5
0.7
B59212R0080B140
Telecom
Leadless disks
A12 ... R212
Page 2 of 6
Please read Important notes and
Cautions and warnings at the end of this document.
Dimensional drawing round disks
Dimensional drawings square disks
Solder pad
Dimensions in mm
Type
d
max
th
max
Contacts
Round disks
A1037
6.6
1.7
for solder connection
A1042
8.1
2.1
for solder connection
A1610
10.1
2.1
for solder connection
A1041
8.1
2.1
for solder connection
A48
7.9
2.7
for clamp connection
A34
6.5
1.7
for clamp connection
A12
5.95
2.15
for clamp connection
A1037
6.6
1.7
for solder connection
A95
7.8
2.6
for clamp connection
A1044
8.1
2.1
for solder connection
A94
7.8
2.1
for clamp connection
Square disks
R212
5.95 x 5.95
2.65
for solder / clamp
connection
Telecom
Leadless disks
A12 ... R212
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
Leadless disks
A12 ... R212
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
Leadless disks
A12 ... R212
Page 5 of 6
Please read Important notes and
Cautions and warnings at the end of this document.
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