Ultra High Precision Bulk Metal
®
Foil Technology
4 Resistor Surface Mount Hermetic Network with
0.5 ppm/°C TCR Tracking and 0.005 % Tolerance Match
SMNH
Vishay Foil Resistors
Document Number: 63092
For any questions, contact:
foil@vishaypg.com
www.foilresistors.com
Revision: 25-Mar-10
1
INTRODUCTION
Vishay model SMNH networks incorporate all the
performance features of Vishay Bulk Metal
®
Foil technology
in a product ready for surface mounting. The 8 pin gull wing
side brazed DIP is the smallest ceramic package. Ceramic
has the advantage of electrical isolation on the underside
and high heat dissipation capability.
Resistors in network form, around the operational amplifier
for example, are called upon to track at changing ambient
temperature, to hold ratio under power and to force the ratio
changes over a period of time to be very low.
The hermeticity, the location of the chips within the package
and the “heat-sink effect” of the ceramic package itself help
preserve uniform conditions inside it. The Bulk Metal Foil
Vishay technology advantage in such a construction assures
remarkable performance due to the following factors:
- fundamentally low TCR
- very small drift with load over time
- common behavior: all drifts move in the same direction
with temperature, load and time
- TCR and tolerance match
- excellent tracking
The major highlights are emphasized by an excellent load life
and shelf life ratio stability.
Vishay hermetic resistor networks are based on fabrication
from a standing inventory of packages and resistor chips.
This permits quick delivery of prototypes since there are no
masks to design or trial processings to be made. Further, it
allows any combination of values, tolerances and circuits.
There are normally no engineering or setup charges, and no
minimum quantities are required. Delivery can be in two
weeks. (See network express prototype service.)
The sequence of fabrication includes selection of chips, die
attachment, wirebonding, value trimming, and hermetic
sealing. The finished product provides the stability
associated with Foil resistors in a hermetically sealed
package.
Hermetic sealing of Vishay’s networks enhances their
already inherently stable environmental performance. The
result is improved load life stability and better performance
during high temperature and moisture exposure.
FEATURES
•
Temperature coefficient of resistance (TCR):
absolute: ± 2 ppm/°C typical
(- 55 °C to + 125 °C, + 25 °C ref.)
tracking: ± 0.5 ppm/°C typical
•
Resistance range: 5
Ω
to 33 k
Ω
•
Vishay 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 rating: at 70 °C
Entire package: 0.4 W
Each resistor: 0.1 W
•
Resistance tolerance match: ± 0.005 %
•
Load life stability per resistor: 0.005 % (0.1 W at 70 °C,
1000 h)
•
Load life stability ratio: 0.005 % (0.1 W at 70 °C)
•
Shelf life stability per resistor: 0.0002 % (2 ppm)
•
Shelf life stability ratio: 0.0001 % (1 ppm)
•
Electrostatic discharge (ESD) up to 25 000 V
•
Short time overload
≤
0.002 % (20 ppm)
•
Non-inductive, non-capacitive design
•
Rise time: 1 ns effectively no ringing
•
Thermal stabilization time < 1 s (nominal value achieved
within 10 ppm of steady state value)
•
Current noise: 0.010 µV
RMS
/V of applied voltage (< - 40 dB)
•
Voltage coefficient: < 0.1 ppm/V
•
Non inductive: < 0.08 µH
•
Non hot spot design
•
Terminal finish: gold plated (lead (Pb)-free)
•
For better performances please contact us
•
Available with Z-Foil technology for improved TCR to
0.2 ppm/°C
•
Compliant to RoHS directive 2002/95/EC
* Pb containing terminations are not RoHS compliant, exemptions may apply
FIGURE 1 - SCHEMATICS
Note:
R
1
and R
2
may
b
e same
v
al
u
e, if desired
SMNH1
R
1
1
8
R
2
3
6
R
2
2
7
R
1
4
5
SMNH2
R
1
8
R
2
3
6
R
2
2
7
R
1
5