The SMR3DZ is an ultra high precision molded surface mountable resistor offering all the elements of precision; including low TCR, tight tolerance, long term stability, low noise, low thermal EMF, and non-measurable voltage coefficient. One of the important parameters influencing stability is the Temperature Coefficient of Resistance (TCR). Although the TCR of foil resistors is considered extremely low, this characteristic has been further refined over the years. The SMR3DZ utilizes ultra high precision Bulk Metal® Z-Foil.
The Z-Foil technology provides a significant reduction of the resistive element’s sensitivity to ambient temperature variations (TCR) and to self heating when power is applied (power coefficient).
Voltage division with tight tracking <2 ppm/°C can be achieved with two randomly selected units even with a large ratio between the two values.
Temperature coefficient of resistance (TCR): ±0.2 ppm/°C typical (–55°C to +125°C, +25°C ref.)
Tolerance: to ±0.01%
Power coefficient of resistance (PCR) “∆R due to self heating": 5 ppm at rated power
Flexible Terminations ensure minimal stress transference from the PCB due to a difference in thermal coefficient of expansions (TCE)
Electrostatic discharge (ESD): at least to 25 kV
Load-life stability: ±0.005% (70°C, 2000 h)
Resistance range: 5 Ω to 80 kΩ
Power rating: to 600 mW at +70°C
Non-inductive, non-capacitive design
Current noise: –40 dB
Voltage coefficient: <0.1 ppm/V
Non hot spot design
Terminal finishes available: lead (Pb)-free, tin/lead alloy
Matched sets with TCR tacking are available upon request