This paper presents a fully integrated shunt-based current sensor that supports a 25-V input common-mode range while operating from a single 1.5-V supply. It uses a highvoltage beyond-the-rails ADC to directly digitize the voltage across an on-chip shunt resistor. To compensate for the shunt’s large temperature coefficient of resistance (∼0.335%/°C), the
ADC employs a proportional-to-absolute-temperature voltage reference. This analog compensation scheme obviates the need for the explicit temperature sensor and calibration logic required by digital compensation schemes. The sensor achieves 1.5-μVrms noise over a 2-ms conversion time while drawing only 10.9 μA from a 1.5-V supply. Over a ±4-A range, and after a one-point trim, the sensor exhibits a 0.9% (maximum) gain error from −40 °C to 85 °C and a 0.05% gain error at room temperature.
Original languageEnglish
Pages (from-to)1-9
Number of pages9
JournalIEEE Journal of Solid State Circuits
Issue number99
Publication statusE-pub ahead of print - 2018

    Research areas

  • Beyond-the-rails, current sensing, high-side, high-voltage (HV) interface circuit, metal shunt resistor, proportional-to-absolute-temperature (PTAT)) voltage reference, temperature compensation, temperature sensor, Δ Σ ADC

ID: 47098920