Leaded ResistoRs
Metal Film Resistors
General Type
Normal & Miniature Style [ MFR Series ]
FeatURes
Power Rating
Resistance Tolerance
T.C.R.
1/6W, 1/4W, 1/2W, 1W, 2W, 3W
±0.5%, ±1%, ±5%
±15ppm/°C, ±25ppm/°C, ±50ppm/°C, ±100ppm/°C
deRatiNG CURVe
iNtRodUCtioN
The MFR Series Metal Film Resistors are
manufactured using a vacuum sputtering system
to deposit multiple layers of mixed metal
alloys and passivative materials onto a carefully
treated high grade ceramic substrate. After a
helical groove has been cut in the resistive layer,
tinned connecting leads of electrolytic copper
are welded to the end-caps. The resistors are
coated with layers of blue color lacquer.
For resistors operated in ambient temperatures above 70°C, power rating must be derated
in accordance with the curve below.
Rated Load (%)
70
100
80
60
40
20
20
40
60
80
100 120 140 160
155 °C
Ambient Temperature (°C)
diMeNsioNs
stYLe
Normal
MFR-12
ød
H
L
øD
MFR-25
MFR-50
MFR100
MFR200
Miniature
MFR25S
MFR50S
MFR1WS
MFR2WS
MFR3WS
diMeNsioN
L
3.4±0.3
6.3±0.5
9.0±0.5
11.5±1.0
15.5±1.0
ød
1.9±0.2
2.4±0.2
3.3±0.3
4.5±0.5
5.0±0.5
H
28±2.0
28±2.0
26±2.0
35±2.0
33±2.0
Unit: mm
ød
0.45±0.05
0.55±0.05
0.55±0.05
0.8±0.05
0.8±0.05
Note:
eLeCtRiCaL CHaRaCteRistiCs
stYLe
Power Rating at 70°C
Maximum Working Voltage
Maximum Overload Voltage
Voltage Proof
Resistance Range
Operating Temp. Range
Temperature Coefficient
MFR-12
1/6W
200V
400V
300V
400V
MFR25s
1/4W
250V
500V
500V
MFR-25
MFR50s
1/2W
300V
600V
350V
700V
MFR-50
MFR1Ws MFR100
1W
400V
800V
700V
500V
1,000V
1,000V
MFR2Ws MFR200
2W
MFR3Ws
3W
1
Ω
- 10M
Ω
& 0
Ω
for E24 & E96 series value
-55°C to +155°C
±15ppm/°C, ±25ppm/°C, ±50ppm/°C, ±100ppm/°C
Note: Special value is available on request
eNViRoNMeNtaL CHaRaCteRistiCs
PeRFoRMaNCe test
Short Time Overload
Voltage Proof
Temperature Coefficient
Insulation Resistance
Solderability
Solvent Resistance of Marking
Robustness of Terminations
Periodic-pulse Overload
Damp Heat Steady State
Endurance at 70°C
Temperature Cycling
Resistance to Soldering Heat
test MetHod
IEC 60115-1 4.13
IEC 60115-1 4.7
IEC 60115-1 4.8
IEC 60115-1 4.6
IEC 60115-1 4.17
IEC 60115-1 4.30
IEC 60115-1 4.16
IEC 60115-1 4.39
IEC 60115-1 4.24
IEC 60115-1 4.25
IEC 60115-1 4.19
IEC 60115-1 4.18
2.5 times RCWV for 5 Sec.
in V-block for 60 Sec., test voltage by type
-55°C to +155°C
in V-block for 60 Sec.
235±5°C for 3±0.5 Sec.
IPA for 5±0.5 Min. with ultrasonic
Direct load for 10 Sec. in the direction of the terminal leads
4 times RCWV 10,000 cycles (1 Sec. on, 25 Sec. off)
40±2°C, 90-95% RH for 56 days, loaded with 0.1 times RCWV
70±2°C at RCWV for 1,000 Hr. (1.5 Hr. on, 0.5 Hr. off)
-55°C
Room Temp.
+155°C
Room Temp. (5 cycles)
260±3°C for 10±1 Sec., immersed to a point 3±0.5mm from the body
aPPRaise
±0.25%+0.05
Ω
By type
By type
>10,000M
Ω
95% Min. coverage
No deterioration of
coatings and markings
≥2.5kg (24.5N)
±1.0%+0.05
Ω
±1.5%+0.05
Ω
±1.5%+0.05
Ω
±0.75%+0.05
Ω
±0.25%+0.05
Ω
Note: Rated Continuous Working Voltage (RCWV) =
Power Rating x Resistance Value
