PTCR Datasheet, PDF (2/2 Pages) List of Unclassifed Manufacturers – Surface Mounted Thermistors

Surface Mounted
Thermistors
PTCR Series
Welwyn Components
Construction
Thick film resistor material, overglaze and organic protection
are screen printed on a 96% alumina substrate.
Marking
All relevant information recorded on the primary package or
reel.
Terminations
Wrap-around terminations are suitable for soldering.
Solderability
Wrap-around terminations have an electroplated nickel barrier
and solder coating. This ensures excellent leach resistance
properties and solderability. They will withstand immersion in
solder at 260°C for 10 seconds.
Solvent Resistance
The chips are resistant to all normal industrial cleaning fluids
suitable for printed circuits.
Performance Data
Load at rated power: 1000 hours at 70°C
Shelf life: 12 months at room temperature
Derating from rated power at 70°C
Dry heat: 1000 hours at 155°C
Climatic category
Long term damp heat
Temperature rapid change
Resistance to solder heat
Voltage proof
∆R%
∆R%
∆R%
∆R%
∆R%
∆R%
volts
Maximum
5
3
2.5
3
2
2
Zero at 155°C
55 / 155 / 56
500
Typical
1
0.5
1
1
0.5
0.5
Application Notes
Operating Temperature Range
The chips themselves can operate at a maximum
temperature of 155°C (see performance claims above). For
soldered chips, the joint temperature should not exceed
110°C. This condition is met when the stated power levels
at 70°C are used.
Mounting
This chips resistor is ideally suited for handling by
automatic methods due to its rectangular shape and small
dimensional tolerances. Electrical connection to a ceramic
substrate or to a printed circuit board can be made by flow
or reflow soldering of wraparound terminations. The
terminations provide good ‘leach’ properties and ensure
reliable contact. Due to the robust construction the resistor
chip can be immersed in a solder bath for 10 seconds at
260°C. This enables the resistor to be mounted on one
side of a printed circuit board and wire-leaded components
on the other side.
Packing
As standard 3000 chips are supplied taped and reeled on
8mm tape to IEC 286-3.
Ordering Procedure
Specify type reference, value and tolerance as shown in
this example of PTCR1206 400R 2%:
Type
Resistance value
(IEC62 code)
Tolerance
(IEC62 code)
F
1%
G
2%
J
5%
1206 400R
G
© Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK
Telephone: [phone] · Facsimile: [phone] · Email: [e-mail] · Website: www.welwyn-tt.com
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Issue C · 08.04