TMCS1101 Precision Isolated Current Sensor

Texas Instruments' TMCS1101 is a galvanically-isolated Hall-effect current sensor that offers DC or AC current measurement with high accuracy, excellent linearity, and temperature stability. A low-drift, temperature-compensated signal chain provides <1.5% full-scale error across the device temperature range.

The input current flows through an internal 1.8 mΩ conductor that generates a magnetic field that is measured by an integrated Hall-effect sensor. This structure eliminates external concentrators and simplifies the design. The low conductor resistance minimizes power loss and thermal dissipation. The inherent galvanic insulation provides a 600 V lifetime working voltage and 3 kV_RMS basic isolation between the current path and circuitry. The device features integrated electrical shielding that enables excellent common-mode rejection and transient immunity.

The output voltage is proportional to the input current with four sensitivity options. The fixed sensitivity allows the TMCS1101 to operate from a single 3 V to 5.5 V power supply, eliminates ratiometry errors, and improves supply noise rejection. The current polarity is considered positive when flowing into the positive input pin. The device is available in unidirectional and bidirectional sensing versions. The TMCS1101 draws a maximum supply current of 6 mA and the sensitivity options are specified over the operating temperature range of -40°C to +125°C.