Two new families of high-performance low-noise Hall-effect current sensors from Allegro MicroSystems Europe feature an isolation voltage of 2100Vrms. Each device comes in +/-5, +/-20, or +/-30A versions, with corresponding sensitivity levels of 185, 100 or 66 mV/A. The new devices, dubbed ACS712 (bidirectional) and ACS713 (unidirectional), will address the growing demand for low-cost, high-accuracy, and compact current- sensing solutions with added functionality.
Chip design is based on the company’s latest low-noise 0.65μm biCMOS process (DABIC6). Parameters such as quiescent output voltage, sensitivity, and temperature coefficient were optimised to minimise noise and total output error.
These current sensors deliver lower noise (twofold reduction) and higher accuracy than their predecessors. In addition, they include an integrated shield that effectively attenuates high dV/dt voltage transients across the leadframe. Consequently, this will suit them for motor-control and high-side current-sensing applications. Moreover, total output error is only 1.5% at room temperature and +/-4% in the industrial temperature range from 40° to +85°C.
The ACS712 and ACS713 incorporate a filter pin that can be used to set the 3dB point with a capacitor. This ultimately reduces the number of external components required to improve sensor resolution.