Diodes Incorporated (Diodes) introduces a series of high-precision current shunt monitors designed to measure small sense voltages across a wide common-mode voltage range in electric vehicles (EVs): the ZXCT21xQ family. Automotive applications for these single-stage instrumentation amplifiers include current sensing of load/rail currents in brushless DC (BLDC) motor controllers, e-compressors, high-power DC-DC converters, on-board chargers (OBC), battery management systems (BMS), ADAS power supplies, and wireless phone chargers.
Low offset voltage (±30μV) and gain error (±0.5% and ±0.8%) of the zero-drift core (typical ±100nV/°C) in these devices enable current sensing across the shunt, with maximum voltage drops as low as 10mV (full-scale). This allows small-value sense resistors to be used in high-accuracy monitoring of large-magnitude currents, while reducing the power lost during measurement. Furthermore, the low quiescent current consumption of 100μA (maximum) also helps to minimize power consumption.
These current monitors have a 0-26V rail-to-rail common-mode sense voltage range (irrespective of supply voltage), enabling both high-side and low-side precision current measurement, while its REF pin enables bi-directional current flow measurement. The ZXCT21xQ family has six voltage gain options (50V/V, 75V/V, 100V/V, 200V/V, 500V/V, and 1000V/V), each with its own unique order number with three accuracy variants.
All devices in the ZXCT21xQ series are AEC-Q100 Grade 1 qualified, manufactured in IATF 16949 certified facilities, and support PPAP documentation. Each operates over a -40°C to +125°C temperature range and are available in industry-standard SOT363 package. The ZXCT21xQ devices are available from $0.321 to $0.451 in 1,000 piece quantities.
