In summary, LEM’s HO-series of Mid range open-loop current transducers based on Hall-effect current sensing technology that measures AC, DC or pulsed currents with a nominal value of 40 to 250 Amps RMS, with a response time of 2.5 or 3.5 µs. The devices are programmable via a serial digital bit-sequence, generated by the system’s host microcontroller. Parameters that are user-programmable include reference voltage, over-current detection limits, fault reporting and low power mode. The HO series delivers its output as a scaled analog voltage; in most systems this will be converted to a digital value by an analog to digital converter (ADC) which requires a reference voltage. The designer can program the transducer to output a reference of 0.5, 1.5, 1.65 or 2.65 V on a dedicated pin. Alternatively, the HO-series can be configured to make measurements relative to an external reference. Offset and gain drift figures are improved compared to previous-generation transducers. The transducer operates from a single supply voltage at 3.3 or 5 V. It occupies a PCB-mountable or panel-mountable, lightweight (5g) package which incorporates three separate primary conductors to allow for multi-range measurement configurations. The HO series has an operating range of -40^oC to 105^oC.