Professional grade approved to BSCECC 40101-803 and 019
Tolerances down to 0.5%
Temperaturecoecientdownto50ppm/°C
Metal Film Resistors
MFR Series
Metal Film Resistors
MFR Series
Professional grade approved to
BSCECC 40101-803 and 019
Tolerances down to 0.5%
Temperature coefficient down to 50ppm/°C
5RFM4RFM3RFM
57.05.04.0sttawC°07 ta gnitar rewoP
Resistance range ohms 10R - 1M 1R0 - 1M 1R0 - 1M
053053002stlovegatlov tnemele gnitimiL
0505C°/mppRCT ≤10:150 >10:100
1 ,5.01 ,5.01%ecnarelot ecnatsiseR
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
All information is subject to Welwyn’s own data and is considered accurate at time of going to print.
© Welwyn Components Limited · Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
These tables indicate the CECC specification requirements, and these are met or exceeded by the corresponding MFR series products.
.
Electrical Data
XEZEXFZF 9 Requirements
Requirements
10 - 10104 CCEC
5.05.052.052.0sttawC°07 ta gnitar rewoP
M1 ot 010M1 ot 01M1 ot 1M1 ot 1smho.egnar ecnatsiseR
053053052052stlovegatlov tnemele gnitimiL
052001052001C°/mppRCT
5.1 to 9.1 : 200 5.1 to 9.1 : 500
1111%ecnarelot ecnatsiseR
KCCCKBCB 308 - 10104 CCEC
52.052.0521.0521.0sttawC°07 ta gnitar rewoP
M1 ot 01M1 ot 01M1 ot 01M1 ot 01smho.egnar ecnatsiseR
052052002002stlovegatlov tnemele gnitimiL
0010500105C°/mppRCT
1 ,5.01 ,5.01 ,5.0 1 ,5.0%ecnarelot ecnatsiseR
derreferp 69E ,42E
seulav dradnatS
211041
051ttaw/C°ecnadepmi lamrehT
551 ot 55-C°egnar erutarepmet tneibmA
11. 09
A subsidiary of
TT electronics plc
Welwyn Components
135
Dimensions (mm) & Weight (g)
Physical Data
L
D
f
d
MFR3 Commercial
Professional
Commercial
Professional
MFR4
MFR5
Product grades available commercial, professional professional
commercial
Type L max
3.7
6.2
6.8
9.0
2.0
2.5
3.0
3.6
22.4
21.0
21.0
19.6
0.45
0.6
0.55
0.8
7.6 0.5
10.2
10.2
12.7
0.6
0.6
1.2
0.1
0.3
0.3
0.5
D max F min d nom PCB
mount
centres
Min
bend
radius
Wt.
nom
Resistors
06.18
General Note
TT Electronics reserves the right to make changes in product specication without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
© TT Electronics plc
www.ttelectronics.com/resistors
BI Technologies IRC Welwyn
AllpartsarePb-freeandcomplywithEUDirecve2011/65/EUamendedby(EU)2015/863(RoHS3)AllpartsarePb-freeandcomplywithEUDirecve2011/65/EUamendedby(EU)2015/863(RoHS3)
Metal Film Resistors
MFR Series
Metal Film Resistors
MFR Series
© Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com 
Welwyn Components
136
Graph 1 – Load for 1000 hours at 70°C: maximum changes
Graph 2 – Load for 1000 hours at 70°C: maximum changes
CECC 40101-019 Actual Performance
Requirements Maximum Typical
Load at commercial rating : 1000 hours at 70°C ∆1 hpa rG eeS8.0% R
Load at CECC rating : 1000 hours at 70°C ∆R % 2 0.5 See Graph 1
Shelf life : 12 months at room temperature ∆R % Not Specified 0.1 0.07
C° 551 t a o r e zgni tareD
Short term overload ∆R % 0.5 0.25 0.03
Climatic ∆R % 2 0.5 0.2
65 / 521 / 55yrogetac c i tami lC
Long term damp heat ∆R % 2 0.5 0.3
Temperature rapid change ∆R % 0.5 0.25 0.05
Resistance to solder heat ∆R % 0.5 0.25 0.02
Vibration and bump ∆R % 0.5 0.1 0.01
70.01.0de i f i ceps to NV/Vµ
) y cneuqe r f f o edac ed a n i ( . e s i oN
G1>G1 >G1>s mh oecnats i ser noi talusnI
n im 004n im 004n im 053s t l ovf oo r p ega t l oV
Pulse handling Data available upon request
Performance Data - Type MFR 3
CECC 40101-019 CECC 40101-803 Actual Performance
Requirements Requirements Maximum Typical
Load at commercial rating :
1000 hours at 70°C ∆2 hpa rG eeS8.0% R
Load at CECC rating :
1000 hours at 70°C ∆R % 2 1 0.5 See Graph 2
Shelf life :
12 months at room temperature ∆R % Not specified Not Specified 0.1 0.07
C° 551 t a o r e zC° 551 t a o r e zgni tareD
Short term overload ∆R % 0.5 0.25 0.25 0.01
Climatic ∆R % 2 1 0.5 0.2
65 / 521 / 5565 / 521 / 55yrogetac c i tami lC
Long term damp heat ∆R % 2 1 0.5 0.3
Temperature rapid change ∆R % 0.5 0.25 0.25 0.04
Resistance to solder heat ∆R % 0.5 0.25 0.25 0.07
Vibration and bump ∆R % 0.5 0.25 0.1 0.01
Noise. (in a decade of frequency) µV/V Not Specified Not Specified 0.1 0.1
Insulation resistance ohms >1G >1G >1G >1G
n im 005n im 005n im 004n im 005s t l ovf oo r p ega t l oV
t s euqe r nopu e l ba l i a v a a t aDgn i l dnah e s l uP
Performance Data - Type MFR 4
*
* CECC requirements are included for reference only; CECC release is not available on MFR3
06.18
General Note
TT Electronics reserves the right to make changes in product specication without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
© TT Electronics plc
www.ttelectronics.com/resistors
BI Technologies IRC Welwyn
Packaging
All MFR resistors are supplied tape packed ready for loading
on to automatic sequencing and insertion machines.
Component wires will not protrude beyond the outside edge
of the tapes.
Alternative packaging available by request.
Lead Formed resistors can also be supplied. Standard options
of Lancet, Radial and Goalpost forming are available.
Graph 3 – Load for 1000 hours at 70°C: maximum changes
Construction
The resistance element is a precisely controlled thin film of
metal alloy sputtered on to a high purity ceramic core,
protected by a moisture-resistant, high dielectric strength
coating applied so that terminations remain completely clear.
Terminations
Material Hot tin dipped copper wire
Strength The terminations meet the requirements of
IEC 68.2.21
Solderability The terminations meet the requirements of
IEC 115-1, Clause 4.17.3.2
Marking
0.5% and 1% tolerance resistors are colour coded with 5
bands. IEC 62 colours are used.
Solvent Resistance
The body protection and marking are resistant to all normal
industrial cleaning solvents suitable for printed circuits.
52
f1f2
66
5
f1 – f 2≤ 1.4 mm
Metal Film Resistors
MFR Series
© Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com 
Welwyn Components
137
CECC 40101-019 CECC 40101-803 Actual Performance
Requirements Requirements Maximum Typical
Load at commercial rating :
1000 hours at 70°C ∆3 hpa rG eeS9.0% R
Load at CECC rating :
1000 hours at 70°C ∆R % 2 1 0.5 See Graph 3
Shelf life :
12 months at room temperature ∆R % Not specified Not Specified 0.1 0.07
C° 551 t a o r e zC° 551 t a o r e zgni tareD
Short term overload ∆R % 0.5 0.25 0.25 0.01
Climatic ∆R % 2 1 0.5 0.2
65 / 521 / 5565 / 521 / 55yrogetac c i tami lC
Long term damp heat ∆R % 2 1 0.5 0.3
Temperature rapid change ∆R % 0.5 0.25 0.25 0.04
Resistance to solder heat ∆R % 0.5 0.25 0.25 0.07
Vibration and bump ∆R % 0.5 0.25 0.1 0.01
Noise. (in a decade of frequency) µV/V Not Specified Not Specified 0.1 0.07
Insulation resistance ohms >1G >1G >1G >1G
n im 007n im 007n im 005n im 007s t l ovf oo r p ega t l oV
t s euqe r nopu e l ba l i a v a a t aDgn i l dnah e s l uP
Performance Data - Type MFR 5
Metal Film Resistors
MFR Series
06.18
General Note
TT Electronics reserves the right to make changes in product specication without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
© TT Electronics plc
www.ttelectronics.com/resistors
BI Technologies IRC Welwyn
11.09
Commercial Grade
Professional Grade. CECC release is available within range
indicated in Electrical Data.
Metal Film Resistors
MFR Series
06.18
General Note
TT Electronics reserves the right to make changes in product specication without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
© TT Electronics plc
www.ttelectronics.com/resistors
BI Technologies IRC Welwyn
Ordering Procedure
Example: MFR4-4K7FI (Professional grade MFR4 at 4.7 kilohms ±1%, Pb-free)
M
F
-
4
K
I
1
2
4
CECC release is available only for professional grade Pb-free parts (code I).
For CECC released product state on order the CECC number and style.
Example: MFR4-4K7FI CECC40101-019 FZ
1
2
3
4
Type Value Tolerance Grade, Finish & Packing
MFR3
E24 = 3/4 characters
E96 = 4/5 characters
R = ohms
K = kilohms
M = megohms
D = ±0.5%
C
MFR3, 4
Commercial
Pb-free (RoHS)
MFR4
F = ±1%
I
MFR4, 5 Professional
MFR5
All above in Standard Packing
MFR3, 4
Ammo
5000/box
MFR5
2500/box