5x5mm isolated SMD current sensors measure dc to 5MHz

Variants allow six sensitivities between 66mV/A (±20A range) and 20.3mV/A (±65A). Response time is typically 40ns.

They are “fast enough for SiC and GaN protection, while also providing low-frequency content for power-conversion control”, said Allegro product manger Matt Hein.

ACS37030 and ACS37032 employ dual signal paths, with one capturing low-frequency and dc current using Hall-effect elements, and the other using an inductive coil to capture high-frequency data.

The coil is designed to increase signal to noise ratio (SNR) as frequency increases, and current is sensed differentially by two Hall plates and two coils to allow interfering common-mode magnetic fields to be ignored.

Packaging is a custom 6pad 5 x 5mm SOIC design, with two larger current tabs (0.6mΩ 2.4nH path) and four standard legs covering: ground, supply, analogue output and either a zero-current voltage reference (ACS37030) or an over-current flag (ACS37032).

Operation is from 3.3V (30mA max) and across -40 to +150°C. Sensitivity error across this temperature range at 150kHz is typically ±2%.

For zero current in, the output is centred around 1.65V ±10mVmax – this is the voltage buffered to the reference output on the …30 part for lower-error use.

In …32 parts, the fault output trips at ~100% of full-scale, positive and negative.

Isolation is 3,500Vrms withstanding, 840Vrms (1,188Vdc) basic and 420Vrms (594Vdc) reinforced.

Electrified vehicle and data centre applications are foreseen.

The ACS37030 and ACS37032 product page can be found here.