Resistors
MELF
Make Possible
Resistors
MELF
Resistors
Welwyn Components
WRM Series
WRM Series
• High reliability
High reliability
pulse handling capability
• Predictable
Predictable pulse handling capability
down
to 0.1%
• Tolerances
Tolerances down
to 0.1%
downtoto
5 ppm/°C
• TCR
TCR down
5 ppm/°C
All parts are Pb-free and comply with EU Directive 2011/65/EU (RoHS2)
Electrical Data
WRM 0102
WRM 0204
WRM 0207
Power rating at 70°C
watts
0.125
0.25
0.4
Resistance range
ohms
4R7 - 110K
R22 – 5M1
R22 – 10 M
Limiting element voltage
TCR
Resistance tolerance
volts
150
200
250
ppm/°C
50
5,10,15, 25, 50, 100
15, 25, 50, 100
%
1
0.1, 0.25, 0.5, 1.0, 2, 5
Standard values
E24 & E96
Thermal impedance
k/W
Ambient temperature range
250
200
°C
Insulation resistance
140
-55 to +125
>1010
ohms
Physical Data
Dimensions (mm) and weight (g)
Type
L
max
D
max
D1
max
WRM 0102
2.2
1.35
1.3
0.3
0.01
WRM 0204
3.7
1.55
1.55
0.5
0.02
WRM 0207
6.1
2.4
2.4
0.5
0.08
Construction
A metal film is deposited onto a high dissipation ceramic
former to which tin plated teminating caps are fitted.
The resistor is adjusted to value by a helical cut in the film
and the body is protected by a lacquer coating.
Marking
Resistance values are colour coded with four bands,
three indicating value and one indicating the multiplier.
(Note this describes standard marking, but certain values
may still be supplied with the addition of a tolerance band
following the multiplier.)
K
min
Weight
L
D
D1
L1
K
Terminations
Material
Plated steel cap.
Solderability The pure tin finish produces ageing free
contacts on which low melting solders can
be used. Dipped area shall be covered with
a smooth and bright solder coating after
3 seconds immersion at 215°C.
Solvent Resistance
The body protection and marking are resistant to all normal
industrial cleaning solvents suitable for printed circuit boards.
General
GeneralNote
Note
Welwyn
Components
reserves
right
to make
changesspecification
in product without
specification
notice or liability.
TT
Electronics
reserves the
right tothe
make
changes
in product
noticewithout
or liability.
Allinformation
informationis issubject
subject
accurateatattime
timeofofgoing
going
print.
All
to to
TT Welwyn’s
Electronics’own
owndata
dataand
and isis considered
considered accurate
to to
print.
© Welwyn Components Limited · Bedlington, Northumberland NE22 7AA, UK
©
TT Electronics
Telephone:
+44 (0) plc
1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
A subsidiary of
www.ttelectronicsresistors.com
TT electronics plc
01. 11
04.15
MELF
MELF
Resistors
Resistors
Make Possible
Welwyn Components
WRM Series
WRM Series
TCR and Tolerance Range
Type
TCR
Tolerance
Reference
5%
2%
1.0%
0.5%
0.25%
0.1%
±50ppm
–
–
4R7 - 110K
–
–
–
±100ppm
R22 – R91
–
–
–
–
–
±50ppm
–
–
1R – 5M1
10R – 1M6
22R – 332K
43R – 332K
±25ppm
–
–
4R7 - 500K
10R – 500K
22R – 402K
43R – 332K
±15ppm
–
–
–
10R – 221K
22R – 221K
43R – 221K
±10ppm
–
–
–
–
22R – 221K
43R – 221K
±05ppm
–
–
–
–
100R – 100K
100R – 100K
±100ppm
R22 – R91
–
–
–
–
–
±25ppm
–
–
10R - 1M
10R – 680K
51R1 - 330K
100R - 100K
±15ppm
–
–
–
51R1 - 10K
51R1 - 10K
100R - 10K
WRM0102
WRM0204
WRM0207
1R-10M
* TC 10ppm & 5ppm is specified over the temperature range -10°C to +85°C.
Performance Data
Test
Results ∆ R/R ±
0204 & 0207: 10R - <75R
& >100K - 332K
0204 & 0207: 75R - 100K
≤ 0.05% + 0.01 Ω
Short time overload*
0102: 4R7 - 110K, 0204 &
0207: R22 - <10R & >332K - 10M
≤ 0.1% + 0.01 Ω
≤ 0.25% + 0.05 Ω
Bending test*
≤ 0.05% + 0.01 Ω
≤ 0.1% + 0.01 Ω
≤ 0.25% + 0.05 Ω
Resistance to soldering heat
≤ 0.05% + 0.01 Ω
≤ 0.1% + 0.01 Ω
≤ 0.25% + 0.05 Ω
Temperature rapid change
≤ 0.05% + 0.01 Ω
≤ 0.1% + 0.01 Ω
≤ 0.25% + 0.05 Ω
≤ 0.25% + 0.05 Ω
≤ 0.25% + 0.05 Ω
≤ 0.5% + 0.05 Ω
Endurance*
Load life
1000h
≤ 0.5% + 0.05 Ω
≤ 0.5% + 0.05 Ω
≤ 1.0% + 0.05 Ω
Climatic sequence*
≤ 0.25% + 0.05 Ω
≤ 0.5% + 0.05 Ω
≤ 1.0% + 0.05 Ω
Damp heat steady state*
≤ 0.25% + 0.05 Ω
≤ 0.5% + 0.05 Ω
≤ 1.0% + 0.05 Ω
< 0.25 µV/V
< 3 µV/V
8000 h
Current noise
Solderability
< 0.05 µV/V
Dipped area shall be covered with a smooth
and bright solder coating of at least 96%
< 0.5 . 106/V
Voltage coefficient
Voltage proof
No flashover or breakdown
* Resistors to be mounted on a PC-board according to IEC 115-1, clause 4.27.1
General Note
TT Electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
©
Components
Limited Bedlington, Northumberland NE22 7AA, UK
©Welwyn
TT Electronics
plc
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
www.ttelectronicsresistors.com
01.11
04.15
MELF
MELF
MELF
Resistors
Resistors
Make Possible
Resistors
Welwyn
Welwyn Components
Components
WRM Series
WRM
Series
WRM Series
Single Pulse
Single Pulse
Maximum Pulse Load
Maximum Pulse Load
WRM 0102
WRM
WRM 0102
0204
WRM
WRM 0204
0207
WRM 0207
100
100
Pulse
Pulse
Load
Load
Pmax
Pmax
W
W
10
10
1
1
0,1
0,1
10 µs
10 µs
100 µs
100 µs
1 ms
1 ms
10 ms
10 ms
100 ms
100 ms
1s
1s
10 s
10 s
Pulse Duration ti
Pulse Duration ti
Continuous Pulses
Continuous Pulses
Continuous
Continuous
Pulse
Pulse
Load
Load
Pmax
Pmax
Maximum Pulse Load
Maximum Pulse Load
WRM 0102
WRM
WRM 0102
0204
WRM 0207
0204
WRM
WRM 0207
100
100
W
W
10
10
1
1
0,1
0,1
10 µs
10 µs
100 µs
100 µs
1 ms
1 ms
10 ms
10 ms
100 ms
100 ms
1s
1s
10 s
10 s
Pulse Duration ti
Pulse Duration ti
Packaging
Packaging
The WRM 0102 and 0204 resistors are supplied reeled on 8mm blister tape.
The WRM 0102 and 0204 resistors are supplied reeled on 8mm blister tape.
WRM 0207 resistors are supplied on 12mm blister tape.
WRM 0207 resistors are supplied on 12mm blister tape.
Packaging complies with the requirements of IEC 286-3.
Packaging complies with the requirements of IEC 286-3.
Ordering
Ordering Procedure
Procedure
Example: WRM0204 at 1 kilohm, 1% tolerance and 50ppm/ºC TCR on a reel of 3000 pieces Example: WRM0204 at 1 kilohm, 1% tolerance and 50ppm/ºC TCR on a reel of 3000 pieces WRM
WRM
Type
Type
0204
0204
C C -
1K0
1K0
F
F
I
I
Size
Size
Packing
Packing
TCR
TCR
Z
Z
C
C
D
D
100ppm/ºC
100ppm/ºC
50ppm/ºC
50ppm/ºC
25ppm/ºC
25ppm/ºC
Y
Y
T
T
V
V
15ppm/ºC
15ppm/ºC
10ppm/ºC
10ppm/ºC
5ppm/ºC
5ppm/ºC
Value (use IEC62 code)
Value (use IEC62 code)
I
I
Tape
Tape
0102
0102
0204
0204
0207
0207
3000 / reel (7”)
3000 / reel (7”)
3000 / reel (7”)*
3000 / reel (7”)*
1500 / reel (7”)
1500 / reel (7”)
Standard
Standard
* High precision parts may be supplied on 1000 piece reels – please enquire
* High precision parts may be supplied on 1000 piece reels – please enquire
Tolerance (use IEC62 code)
Tolerance (use IEC62 code)
B
B
C
C
0.1%
0.1%
0.25%
0.25%
D
D
F
F
0.5%
0.5%
1%
1%
G
G
J
J
2%
2%
5%
5%
© Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK
©
Welwyn
Northumberland
NE22
7AA, UK
Telephone:
+44Components
(0) 1670 822181Limited
· Facsimile:Bedlington,
+44 (0) 1670
829465 · Email:
info@welwyn-tt.com
· Website: www.welwyn-tt.com
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
General Note
TT Electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
01.11
01.11
www.ttelectronicsresistors.com
© TT Electronics plc
04.15