VPR220Z (Z-Foil)

Vishay Foil Resistors

Ultra High Precision Z-Foil Power Resistor in

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

Tolerance to ± 0.01 % and Power Rating to 8 W

www.vishay.com

For any questions, contact: foil@vishay.com

Document Number: 63064

2

Revision: 22-Sep-08

Notes

1. Whichever is lower.

2. Heat sink chassis dimensions and requirements per

MIL-PRF-39009:

3. Inductance (L) due mainly to the leads.

4. The resolution limit of existing test equipment (within the

measurement capability of the equipment, or “essentially zero”).

5. µV/°C relates to EMF due to lead temperature difference.

TABLE 2 - SPECIFICATIONS

Load Life Stability

at 2000 h

± 0.05 % max.

ΔR under full

rated power at + 25 °C

Power Rating at + 25 °C

Further derating not

necessary.

Current Noise

< 0.010 µV (rms)/V of applied

voltage (- 40 dB)

High Frequency Operation

Rise time

Capacitance (C)

1 ns

0.1 µH maximum: 0.03 µH typical

1.0 pF maximum: 0.5 pF typical

< 0.1 ppm/V

Operating Temperature

Range

- 55 °C to + 150 °C

Maximum Working

Voltage

300 V. Not to exceed power

rating.

0.15 µV/°C maximum

(lead effect)

DIMENSION

INCHES

mm

L

6.00

152.4

W

4.00

101.6

H

2.00

50.8

T

0.04

1.0

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

+ 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 - VPR220Z TESTS:

5R, 10 UNITS

+ 500

+ 400

+ 300

+ 200

+ 100

0

- 100

- 200

- 300

- 400

- 500

Test Type

(All tests performed on same resistors in succession)

Initial RC

Low

Temp.

Operation

Short Time

Overload

Post

Drying

Moisture

Resistance

Insulation

Resistance

Initial RC

Terminal

Strength

FIGURE 5 - VPR220Z LOAD LIFE, 10 k

Ω

+ 500

+ 400

+ 300

+ 200

+ 100

0

- 100

- 200

- 300

- 400

- 500

Time (h)

0

500

1000

1500

2000