IN Brief:
- The CUR 3020 provides selectable 250kHz and 500kHz bandwidths, with 0.86µs typical device response specified at 500kHz.
- TDK specifies up to 1% sensitivity drift and 5mV offset drift over −40°C to 150°C; complete sensing assemblies require their own validation.
- The AEC-Q100 Grade 0 IC offers programmable analogue output and broken-wire diagnostics, with samples available on request.
TDK has introduced the Micronas CUR 3020, a programmable Hall-effect sensor IC designed for use with C-core magnetic concentrators in traction inverters, battery disconnect systems and industrial power converters. It provides selectable 250kHz and 500kHz bandwidths, an adjustable analogue output and diagnostic functions for circuits that need to detect rapid changes in current. The sensor's electrical specifications apply to the IC; complete measurement performance also depends on the magnetic circuit and connected electronics.
The sensor measures magnetic flux density rather than conductor current directly. In the intended arrangement, a magnetic core concentrates the field generated by current passing through a conductor, with the Hall element positioned to measure that field. The output then depends on the current, the magnetic circuit and the sensor's programmed response. Core geometry, installation tolerances and stray magnetic fields therefore remain part of the measurement design; installing the IC does not by itself establish an accurate current measurement.
The specified sensitivity range extends from 4.2 to 67.4mV/mT. This adjustment allows developers to match the analogue output to the field produced by different current ranges and magnetic concentrator designs. Its quiescent output is nominally centred on 2.5V and can be adjusted, allowing positive and negative currents to be represented as voltages above and below the zero-current point. Sensitivity and quiescent-voltage offset are stored through EEPROM-based calibration, with three programming approaches described in the product documentation.
Bandwidth is a significant design choice because the inverter's current waveform can contain rapid switching-related changes alongside the fundamental current being controlled. The 250kHz setting provides a lower-noise option, whereas 500kHz extends the response to faster variations. The company's output-referred noise figures at 25°C are 0.75mV RMS at 250kHz and 1.5mV RMS at 500kHz for a specified 10mV/mT sensitivity. A wider bandwidth does not remove the need to assess noise, filter design and the sampling behaviour of the downstream controller.
At the 500kHz bandwidth setting, TDK specifies a typical IC response time of 0.86 microseconds, with a maximum of 1.5 microseconds under the published conditions. That figure measures the component's response; it is not the end-to-end response of a current-sensing assembly or an inverter protection loop. The concentrator, output filtering, wiring, analogue-to-digital conversion, firmware and protection logic can add delay. The controller's acquisition range must also accommodate the IC's output swing and programmable clamps if faults and overcurrent events are to be interpreted correctly.
For the IC, TDK lists a maximum sensitivity drift error of 1% and maximum offset drift error of 5mV over −40°C to 150°C, together with a specified maximum linearity error of 0.2% for the device. These figures describe the CUR 3020's electrical characteristics under the supplier's measurement conditions. They do not include errors introduced by the C-core's material and geometry, conductor placement, stray fields or the receiving circuitry. An assembly-level accuracy claim requires a calibration and error budget covering those elements, especially where current feedback is used to control switching or trip a protection function.
Protection and diagnosis are integrated into the IC. TDK lists supply under- and overvoltage detection, reverse-voltage protection, individually selectable output clamps, detection of open ground or supply connections and programmable overtemperature diagnosis. These measures can help a controller distinguish certain sensor faults from genuine current changes, provided the system monitors and responds to the resulting outputs. They should not be confused with certification of an entire traction inverter's functional safety design.
The CUR 3020 is qualified to AEC-Q100 Grade 0, while the manufacturer's table lists an ambient operating-temperature limit of 165°C. Its quoted temperature drift figures stop at 150°C, so they cannot be extended to the highest operating temperature without further evidence. Packaging, mounting and adjacent power-electronic components can also alter the temperatures experienced by the completed sensor module; thermal validation remains part of its qualification.
The CUR 3020 wafers are manufactured at TDK's Freiburg facility in Germany and offers the device in a four-pin TO-92 package with lead-forming options. That package must be positioned consistently in the C-core gap if production units are to reproduce a validated transfer function. Samples are available on request, but the manufacturer has not announced volume delivery of every programmed configuration. Selection will depend on the magnetic design, required current span, thermal conditions and the controller's handling of diagnostic outputs.
