New Generation of Secondary Standards Hermetically Sealed Construction Ultra High
Precision Z-Foil Technology Resistors with TCR of ± 0.2 ppm/°C
, Tolerance of ± 0.001 %
and Load Life Stability of ± 0.002 %
(Metrology, Laboratory, Instrumentation, Industrial)
HZ Series (Z-Foil) with Zero TCR
Vishay Foil Resistors
Document Number: 63120 For any questions, contact: foil@vishaypg.com www.foilresistors.com
Revision: 25-Mar-10 1
INTRODUCTION
The Z-Foil based oil filled, hermetically sealed HZ Series
resistors represent an industry breakthrough. The hermetic
sealing eliminates the ingress of moisture and oxygen, while
the oil acts as a thermal conductor, thus eliminating
long-term degradation elements of unsealed resistors, while
at the same time allowing the device to accept short periods
of overload without degradation.
The Z-Foil technology provides a significant reduction of the
resistive components, sensitivity to ambient temperature
variations (TCR) and applied power changes (PCR). When
combined with the hermetic sealing and oil filling, the
HZ Series resistors become the most precise and stable
resistors available. They are used as the most precise
secondary standards for ultra precision metrology.
With accuracies of ± 0.001 % (10 ppm) and a resistance
range from 5 to 1.1 M and long term shelf life of less than
2 ppm, these devices are virtually secondary standards that
can be carried in sets for daily or periodic calibration of
factory measurement equipment.
The HZ Series is available with laboratory and metrology
level precision and long-term stability with additional
in-house oriented processes such as: chip stabilization,
special TCR plotting, additional treatments for ultra
stability and special post manufacturing operations
(PMO). (Please refer to the last page)
Note
• For maximum TCR < 1 ppm/°C, see VHP100 and contact
application engineering
FEATURES
Temperature coefficient of resistance (TCR):
± 0.2 ppm/°C typical (- 55 °C to + 125 °C,
+ 25 °C ref.). For ultra high performances
(instrumentation and metrology) please refer to
the last page
Resistance range: 5 to 1.1 M (higher or lower values of
resistance available)
Foil resistors are not restricted to standard values; specific
“as required” values can be supplied at no extra cost or
delivery (e.g. 1K2345 vs. 1K)
Power coefficient “R due to self heating”:
5 ppm at rated power with the Z-Foil technology
Tolerance: to ± 0.001 % (10 ppm)
Load life stability to ± 0.002 % (20 ppm) at 25 °C, 2000 h
at rated power
Load life stability, can be considerably improved
through in-house stabilization
Shelf life stability: 2 ppm for at least 6 years
(unaffected by humidity)
Electrostatic discharge (ESD) up to 25 000 V
Power rating: 0.3 W to 2.5 W at + 25 °C (depending on
model - see table 2)
Non-inductive, non-capacitive design
Non hot spot design
Rise time: 1 ns effectively no ringing
Current noise: 0.010 µV
RMS
/V of applied voltage (< - 40 dB)
Thermal EMF: 0.05 µV/°C typical
Voltage coefficient: < 0.1 ppm/V
Thermal stabilization time < 1 s (nominal value achieved
within 10 ppm of steady state value)
Non-inductive: < 0.08 µH
Terminal finish available: lead (Pb)-free or tin/lead alloy
Impervious to harmful environments - oil filled
Prototype quantities available in just 5 working days
or sooner. For more information, please contact
foil@vishaypg.com
For better performances (values, TCR, tolerance, stability),
please contact us
TABLE 1 - TCR VS. RESISTANCE VALUE
RESISTANCE VALUE
()
TYPICAL TCR AND
MAX. SPREAD
(- 55 °C to + 125 °C, + 25 °C ref.)
(ppm/°C)
100 to < 1M1 ± 0.2 ± 2
50 to < 100 ± 0.2 ± 3
5 to < 50 ± 0.2 ± 4
FIGURE 1 - SHELF LIFE - VHA518-11
12K9 VS. QHE
Time (Days)
Resistance Change (ppm)
0 100 200 300 400 500 600 700 800 900 1000
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
- 0.1
