H Series
Vishay Foil Resistors
Hermetically Sealed High Precision Bulk Metal® Foil
Technology Resistors with TCR of 2 ppm/°C, Tolerance
of 0.001 % and Load Life Stability of 0.005 %
FIGURE 2 - TRIMMING TO VALUES
FIGURE 3 - FOIL RESISTOR TYPICAL
TCR CURVE
(Conceptual Illustration)
+ ꢄꢆꢃ
+ ꢄꢃꢃ
+ ꢆꢃ
Current Path
Before Trimming
Interloop Capacitance
Reduction in Series
C Alloy ꢀ ꢁꢁmꢂ/C
Δ
R
ꢃ
R
Current Path
After Trimming
Trimming Process
(ꢁꢁm)
- ꢆꢃ
Mutual Inductance
Reduction due
to Change in
- ꢄꢃꢃ
- ꢄꢆꢃ
- ꢀꢃꢃ
Removes this Material
from Shorting Strip Area
Changing Current Path
and Increasing
ꢀ ꢁꢁmꢂ/C
Current Direction
Resistance
- ꢆꢃ
- ꢆꢆ
- ꢀꢆ
ꢃ
+ ꢀꢆ
+ ꢆꢃ
+ 7ꢆ + ꢄꢃꢃ + ꢄꢀꢆ
Temꢁerature (/C)
Note: Foil shown in black, etched spaces in white
TABLE 2 - MODEL SELECTION
STANDARD RESISTANCE
DIMENSIONS3)
RESISTANCE
RANGE
MAXIMUM POWER AVERAGE
TOLERANCE
MODEL
CONSTRUCTION
BRIEF
WORKING RATING
WEIGHT
(g)
NUMBER
(Ω)
VOLTAGEꢀ) at + ꢀꢆ /C
TIGHTEST LOOSEST
INCHES
mm
(
Ω
)
(ꢅ)
W: 0.185 0.020
L: 0.435 0.020
4.70 0.51
11.05 0.51
Oil-filled, tinned
5 to 100K
> 100K to 150K
0.3 W
0.2 W
copper leads, nickel H: 0.430 0.020** 10.92 0.51
VHP202
300
1.4
shell, kovar and
glass header
LL: 1.000 0.125
25.4 3.18
LS: 0.150 0.0104) 3.81 0.25
ST: 0.095 max.
2.41 max.
L: 0.625 0.031
D: 0.375 0.031
LL: 1.000 min.
15.88 0.79
9.53 0.79
25.4 min.
5 to 100K
> 100K to 150K
0.3 W
0.2 W
VHA412
VHA414
VHA512*
250
4.6
7.3
6.3
L: 1.000 0.031
D: 0.375 0.031
LL: 1.000 min.
25.4 0.79
9.53 0.79
25.4 min.
1)
1K to
0.001 0.1
0.0025 0.1
0.005 0.1
0.01 0.1
0.02 0.1
0.05 0.1
0.1 0.1
5 to 200K
> 200K to 335K
0.5 W
0.3 W
350
500 to < 1K
50 to < 500
30 to < 50
20 to < 30
10 to < 20
5 to < 10
L: 0.625 0.031
D: 0.500 0.031
LL: 1.000 min.
15.88 0.79
12.7 0.79
25.4 min.
5 to 300K
> 300K to 500K
0.75 W
0.4 W
350
5 to 400K
> 400K to 668K
5 to 500K
> 500K to 835K
5 to 600K
> 600K to 1M
1.0 W
0.5 W
1.25 W
0.6 W
1.5 W
0.7 W
Oil-filled,
tinned copper leads,
tinned brass shell,
kovar and
VHA516-4*
VHA516-5*
VHA516-6*
L: 1.000 0.031
D: 0.500 0.031
LL: 1.000 min.
25.4 0.79
12.7 0.79
25.4 min.
500
9.2
glass end bells
5 to 700K
> 700K to 1M17
5 to 800K
> 800K to 1M34
5 to 900K
> 900K to 1M5
5 to 1.0M
> 1.0M to 1M67
5 to 1.0M
> 1.0M to 1M84
1.75 W
0.8 W
2.0 W
0.9 W
2.25 W
1.0 W
2.5 W
1.1 W
2.5 W
1.2 W
VHA518-7*
VHA518-8*
VHA518-9*
VHA518-10*
VHA518-11*
L: 1.500 0.031
D: 0.500 0.031
LL: 1.000 min.
38.1 0.79
12.7 0.79
25.4 min.
600
13.5
Notes
* Available in a 4-lead terminal
** 0.375 H available
See next page for numbered footnotes
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For any questions, contact: foil@vishay.com
Document Number: 63006
Revision: 14-Nov-07