News and New Products

Sense resistor’s low TCR ensures consistency

By Bill Schweber -- EDN, 5/26/2005

A common way to sense current in motors and power supplies is to use a low-value resistor in series with the load, but any drift in this resistor affects reading accuracy. The lead-free TLR-75ppm from KOA Speer Electronics features TCR (temperature-coefficient resistance) of 75 ppm/°C and is available in various resistance and power-handling combinations (Picture). The 2B, 2H, and 3AW sizes come in 1206, 2010, and 2512 cases have 2- to 20-, 2- to 10-, and 3- to 8-mÙ resistances, respectively, with 0.5, 1, 2W power ratings. All devices have 1% basic tolerance. The price is 23 cents (1000).

KOA Speer Electronics Inc, www.koaspeer.com.