Document Number: 63116

For any questions, contact: foil@vishay.com

www.vishay.com

Revision: 16-Jul-07

1

VPR221Z (Z-Foil)

Vishay Foil Resistors

Ultra High Precision Z-Foil 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)

Any value at any tolerance available within resistance range

INTRODUCTION

The Z-Foil Technology provides a significant reduction of the

resistive component’s sensitivity to ambient temperature

variations (TCR) and applied power changes (PCR).

VPR221Z provides high rated power, excellent load life

stability , low Temperature Coefficient (TCR) and low Power

Coefficient (PCR) - all in one resistor. ± 0.05 ppm/°C

Absolute TCR removes error due to temperature gradients.

By taking advantage of the overall stability and reliability of

Vishay

Bulk

Z-Foil

resistors,

designers

can

significantly reduce circuit errors and greatly improve overall

circuit performances.

Model VPR221Z is a 4 lead kelvin connected device.

Our Application Engineering Department is available to

advise and make recommendations. For non-standard

technical requirements and special applications, please

contact us.

Notes

1. MIL-Range (- 55 °C to + 125 °C, + 25 °C Ref.)

•

Contact Applications Engineering for other available values

FEATURES

± 0.05 ppm/°C typical (0 °C to + 60 °C)

± 0.2 ppm/°C typical (- 55 °C to + 125 °C,

+ 25 °C Ref.) (see table 1)

• Tolerance: to ± 0.01 %

• Power Coefficient “ΔR due to self heating”

4 ppm/W typical

• Rated Power: 8 W chassis mounted (MIL-PRF-39009)

• Load Life Stability: to ± 0.005 % at 25 °C for 2000 hours,

at 1.5 W

• Resistance Range: 0.5 Ω to 500 Ω

• Electrostatic Discharge (ESD) above 25 000 V

• Short Time Overload ≤ 0.001 % (10 ppm)

• Non Inductive, Non Capacitive Design

• Rise Time: 1 ns without ringing

• Current Noise < - 40 dB

• Thermal EMF: 0.05 µV/°C typical

• Voltage Coefficient < 0.1 ppm/V

• Non Inductive: < 0.08 µH

• Non Hot Spot Design

• Terminal Finishes available: Lead (Pb)-free

Tin/Lead Alloy

• Any value available within resistance range (e.g. 1K234)

• For better performances please contact us

APPLICATIONS

• Automatic Test Equipment (ATE)

• High Precision Instrumentation

• Electron Beam application

• Current Sensing applications

• Pulse applications

• Military

• Power amplifier

• Power supplies

* Pb containing terminations are not RoHS compliant, exemptions may apply

TABLE 1 - TCR AND TOLERANCE

RESISTANCE

RANGE (

Ω)

TIGHTEST

RESISTANCE

TOLERANCE

TYPICAL TCR AND

0.5 to < 1

± 0.05 %

± 0.2 ppm/°C ± 2.8 ppm/°C

1 to < 10

± 0.02 %

± 0.2 ppm/°C ± 2.3 ppm/°C

10 to 500

± 0.01 %

± 0.2 ppm/°C ± 1.8 ppm/°C

FIGURE 1- POWER DERATING CURVE

Available

Pb-free

RoHS*

COMPLIANT

I

1

E

1

E

2

I

2

R

V

I

I

Ambient Temperature (°C)

100

75

50

25

0

- 75

150

- 25

25

75

125

- 50

0

50

100

- 55 °C