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The project described here is a 3-Phase isolated Hall-effect current sense amplifier with +/-600-V working voltage range. The current sensor senses magnetic flux generated from current passing through the lead frame at common-mode voltages 0 to 600V DC and provides proportional output voltage. The circuit is based on TMCS1101 IC which is a galvanically isolated Hall-effect current sensor capable of DC or AC current measurement with high accuracy, excellent linearity, temperature stability and has a bandwidth of 80KHz. 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 measured by an integrated Hall-effect sensor. This structure eliminates external concentrators and simplifies design. Low conductor resistance minimizes power loss and thermal dissipation. Inherent galvanic insulation provides a 600-V lifetime working voltage and 3-kVRMS basic isolation between the current path and circuitry. Integrated electrical shielding enables excellent common-mode rejection and transient immunity. The output voltage is proportional to the input current with 50mV/A sensitivity. Fixed sensitivity eliminates radiometry errors, and improves supply noise rejection. The current polarity is considered positive when flowing into the positive input pin. The circuit is capable of sensing bidirectional current with +/-46A measurement range.”

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