1225-size Current-Sense Chip Resistor | IRC

IRC's 1225-size Current-Sense Chip Resistor Is Industry's Smallest 3-Watt Device IRC's 1225-size Current-Sense Chip Resistor Is Industry's Smallest 3-Watt Device

IRC ultra-low resistance thick film surface mount resistor are capable of handling power dissipation of up to 3W in an industry-standard 1225 chip (a chip size typically rated at 1W). Designated the LRF3W Series, the resistors employ a proven four terminal "Kelvin connection" design to achieve ultralow resistance values of 0.003 used primarily for current-sensing in electronic circuits for automobiles and other applications that require high power handling capabilities with low resistance.

The LRF3W Series chips are the industry's smallest three-watt current sense resistors. This level of power in a standard flat chip is critical for automotive design engineers because of the need for them to corporate a current-sensing function into so many of the electronic systems on today's vehicles.

In addition to automotive electronics, the LRF3W Series resistors are finding application in precision current-sensing, battery-charging and feedback circuits in computers, instrumentation, power supplies and motor controls wherever current-sense devices are used, Wade added.

Rated for a full 3W @ 70 degrees C, the LRF3W Series resistors feature resistance values as low as 0.003 to 0.100, in tolerances to 1% and with TCRs (temperature coefficient of resistance) of +/-100 ppm/degrees C. They are rated for operation from -55 degrees C to +150 degrees C.

The ceramic-based construction of the resistors makes them considerably more rugged and stable than metal strip resistors since they are not subject to stress annealing, which can cause resistance changes at the elevated temperatures and higher wattages found in the automotive environment. The LRF3W's industry-standard chip size (1225) is compatible with automated assembly equipment, and wave or reflow soldering methods.