Miniature surface-mount current-sense resistors maximise performance and precision
Welwyn Components has introduced metal element resistors in miniature surface-mount 1206 and 2010 sizes, delivering high surge-withstand capability and low parasitic inductance for precision current sensing in monitoring, control, protection and measurement circuits.
The 1-watt ULR1S in the 1206 outline and 1.5-watt ULR15S in the 2010 outline are available in ultra-low ohmic values from 1mΩ to 10mΩ, in 0.5mΩ increments up to 6mΩ. 7mΩ, 8mΩ, 9mΩ and 10mΩ values complete each series. The devices can be specified with either 1% or 5% tolerance, and have low temperature dependency of 50ppm/°C for consistent accuracy over a wide temperature range.
Combining high precision with very low ohmic values, these resistors maximise conversion efficiency and minimise the effect of sensing on the surrounding circuitry. A single ULR1S or ULR15S can replace multiple chip resistors of higher resistance in applications such as motor control, process control, switching circuits, lighting controls, power-conversion equipment, and safety systems.
The all-metal construction of these resistors also yields a wide operating temperature range, from –55°C to +170°C.. This makes them an ideal choice for applications such as industrial and automotive.
Case Studies
Chip Resistor Replaces Surface Mount Wirewound
When a major manufacturer of industrial circuit breakers wanted to re-engineer their core range of products, one area of focus was on how to provide power resistive products in an SMD assembly...
