Low resistance values are important for high efficiency current sensing in that lower values mean less wasted power on the current sensing measurement itself. But sensing low resistance values becomes challenging because of lead resistance. Using a four terminal shunt resistor eliminates the detrimental effects of lead resistance on the current sensing measurement operation.
Stackpole recently added two sizes to their HCSK series, providing more design flexibility with smaller size options and different terminal placement options.
The HCSK4026 is the same element size as the existing 2725, but the terminations extend outward from the part instead of under. The HCSK1216 provides similar four terminal connection performance that consumes 75% less space than the 2725 size.
The HCSK1216 and 4026 are available in 0.5 and 1 milliohm resistance values in tolerances as low as one percent and 50 ppm TCR. Applications include power management, power modules, battery charging, frequency converters, hybrid power current sensing, engine and motor controls, and PC graphics and motherboards.
Pricing will vary depending on size, and tolerance, and is $0.28 each for the HCSK1216 in 1% tolerances and $0.50 for the HCSK4026 and 2725 in one percent tolerances for example.