Document Number: 63127

For any questions, contact: foil@vishay.com

www.vishay.com

Revision: 11-Jun-07

2

VPR221SZ (Z-Foil)

Ultra High Precision Z-Foil Surface Mount Power Resistor

in TO-220 Configuration with TCR of ± 0.05 ppm/°C, PCR

of 4 ppm/W and Load Life Stability of ± 0.005 % (50 ppm)

Vishay Foil Resistors

FIGURE 2 - TRIMMING TO VALUES

(Conceptual Illustration)

Mutual Inductance

Reduction due

to Change in

Current Direction

Current Path

Before Trimming

Note: Foil shown in black, etched spaces in white

Interloop Capacitance

Reduction in Series

Trimming Process

Removes this Material

from Shorting Strip Area

Changing Current Path

and Increasing

Resistance

Current Path

After Trimming

FIGURE 3 - TYPICAL TCR CURVE Z-FOIL

(for more details see table 1)

+ 500

+ 200

+ 100

0

- 100

- 200

- 300

- 500

- 55

- 25

+ 25

+ 60

+ 75

+ 100

+ 125

Ambient Temperature (°C)

ΔR

R

(ppm)

0

0.05 ppm/°C

- 0.1 ppm/°C

0.1 ppm/°C

0.14 ppm/°C

0.2 ppm/°C

- 0.16 ppm/°C

- 400

+ 300

+ 400

FIGURE 4 - VPR221SZ FORMING

DIMENSIONS in inches (millimeters)

0.365 (9.27) Ref

0.050 ± 0.005

(1.27 ± 0.13)

0.150 ± 0.008

(3.81 ± 0.20)

0.015 ± 0.002

(0.38 ± 0.05)

0.078 ± 0.005

(1.98 ± 0.13)

Heat Sink

0.695 ± 0.010

(17.65 ± 0.25)

0.090 ± 0.010

(2.29 ± 0.25)

0.090 (2.286) Ref

0.110 (2.79) Ref

Flush with Heat Sink

Within ± 0.002 (± 0.05)

Before Forming

After Forming

FIGURE 5 - VPR221SZ DIMENSIONS in

inches (millimeters)

E

2

0.050 ± 0.005

(1.27 ± 0.13)

0.150 ± 0.008

(3.81 ± 0.20)

0.615 Max

(15.62)

0.078 ± 0.005

(1.98 ± 0.13)

0.015 ± 0.002

(0.38 ± 0.05)

0.030 ± 0.002

(0.76 ± 0.05)

0.100 ± 0.005

(2.54 ± 0.13)

0.400 ± 0.010

(10.16 ± 0.25)

VISHAY

1R0 1 %

0101

0.245 ± 0.010

(6.22 ± 0.25)

0.141 ± 0.005 Dia

(3.58 ± 0.13)

0.540 ± 0.040

(13.72 ± 1.02)

0.115 ± 0.005

(2.92 ± 0.13)

0.050 ± 0.005

(1.27 ± 0.13)

0.200 ± 0.030

(5.08 ± 0.76)

E

1

I

2

I

1

VPR221SZ

FIGURE 6 - LAND PATTERN DIMENSIONS in inches (millimeters)

0.050 ± 0.010

(1.27 ± 0.25)

0.120 ± 0.010

(3.05 ± 0.25)

0.10 ± 0.005

(2.54 ± 0.12)