Diodes Incorporated releases high-precision, bi-directional current monitors. The ZXCT21x current monitor series are single-stage instrumentation amplifiers designed to accurately measure very small sense voltages across a wide range of common-mode voltages up to 26 V. Their applications include current sensing of load/rail currents in BLDC motor control, telecom power, solar inverters, and battery-charged equipment.
The ZXCT21x’s low offset voltage (30 μV) with zero-drift core (100 nV/ºC) enables it to achieve high-precision current sensing, with maximum drops across the shunt resistor, to as low as 10mV full scale. This allows the use of small-value sense resistors to monitor large currents, thus reducing power loss caused by the measurement.
The series has six fixed voltage gain options in 50V/V, 75V/V, 100V/V, 200V/V, 500V/V, and 1000V/V. The devices measure the voltage across the shunt at common-mode voltages from -0.3 V to 26 V, independent of supply voltage.
These devices operate from a 2.7 V to 26 V power supply with a maximum 100 μA supply current. In addition, a REF pin enables bi-directional current flow measurement capability.
All versions are available in the very small U-QFN1418-10 and SOT363 packages and support a -40ºC to +125ºC ambient temperature range.
Key features
- Offset Voltage as Low as 30 µV - Minimizes errors when using low-value sense resistors
- Gain Error as Low as 0.5% - Maintains accurate gain control across temperature and common mode voltage
- Common Mode Range -0.3 V to 26 V - Accurately measures high-side and low-side currents, including short-circuited loads
- Wide Operating Voltage Range: 2.7 V to 26 V - Provides options for powering separately or from monitored supply
- Robust ESD Capability (HBM: 5 kV, CDM: 1.5 kV) - Improves system reliability
Key applications
- Notebook computers
- Server farms
- Telecoms
- Instrumentation
- Battery charging and discharging
- High-performance video cards
- Industrial power supplies
- Current sensing (high-side/low-side)
