Electronic Components Blog

Friday, 13 March 2015 11:18

Isabellenhütte expands its portfolio for medium and lower performance requirements

Isabellenhütte expands its portfolio for medium and lower performance requirements

New CMx SMD resistor series from Isabellenhütte:
High stability, even at low levels of performance

Isabellenhütte now also offers resistors for medium and lower performance requirements in the SMD-mountable precision and power resistor segment, closing a gap in its range. The existing SMx and VMx SMD series include resistors for high-end applications. The new CMx series meets the market demand for reduced technical performance and is available in the standard sizes 2512, 2010 and 1206. The new resistors work in the temperature range from -65 to 170 °Celsius, making them suitable for both industrial applications and as components in vehicle applications. In the automotive sector, they comply with the AEC-Q200 specifications and fulfil the criteria of RoHS 2011/65/EU.

Low TCR across the entire range of temperatures
Despite their reduced resistance, the CMx resistors offer the same quality features as other Isabellenhütte resistors, such as high long-term stability, optimum temperature coefficients and high load capacity. The TCR of the entire range is below 75 ppm/K. “Unlike many other resistors in the lower performance range, our low temperature coefficient applies to the whole resistance range and load capacity is guaranteed, even when the temperature of the contact points is high,” confirms Eugen Löwen, Application Management Sales Components at Isabellenhütte. The TCR of resistors made by other manufacturers varies across the value range and nominal load depends on the ambient temperature. However, contact point temperature is the key point of reference for applications. Together with the load and stability of the component, it is decisive. Users also benefit from the long-term stability of Isabellenhütte’s technology. Long-term stability after 2,000 hours of operation is excellent, with deviation of less than 1.0 per cent from the original values for all sizes. “While other manufacturers can match that performance, few can achieve the contact point temperatures offered by Isabellenhütte resistors, for example 100 °Celsius,” says Eugen Löwen. All three versions have a very high load capacity. The CMS has resistance of 10 to 500 mOhm at a nominal capacity of 2 watts. The CMP also has resistance of 10 to 500 mOhm with load capacity of 1 watt. The CMK offers resistance of 10 to 100 mOhm and a load capacity of 0.5 watts.

Technical details CMx:

Resistance values  10 to 500 mOhm (CMS, CMP) 
  10 to 100 mOhm (CMK)
 Tolerance  1 % / 5 %
 Temperature coefficient (20-60 °C)  < 75 ppm/K
 Temperature range  -65 °C to +170 °C
 Power rating  2 W (CMS)
   1 W (CMP)
   0.5 W (CMK)
 Internal heat resistance  < 35 K/W (CMS)
   < 50 K/W (CMP)
  < 80 K/W (CMK)
Inductance < 3 nH
Dielectric withstanding voltage 200 V AC/DC
Stability (nominal load) < 1.0 % at TK = 100 °C (CMS)
Deviation after 2.000 hrs < 1.0 % at TK = 120 °C (CMP)
TK = Terminal temperature < 1.0 % at TK = 130 °C (CMK)