±1% accuracy and 1 µs response — the two numbers that drive the selection
The CZ3703 is a Hall-effect, open-loop coreless current sensor housed in a 10-pin PowerSOIC (7.70 mm wide) that measures bidirectional AC and DC currents up to 36 A with ±1% accuracy across the full operating range. Linearity is ±0.13% — the deviation between output and a perfect transfer function across the current range. For a current-measurement front-end that feeds a Σ-Δ ADC, this error sits well below the quantisation floor and the integrator's own drift. The 1 µs response time means the sensor settles to within the rated accuracy after a current step in roughly one microsecond — fast enough for overcurrent protection loops that rely on the host controller's hardware fault pin rather than firmware.
PowerSOIC thermal and layout demands for 36 A continuous
The 10-SMD PowerSOIC package thermal pad carries the full 36 A through the source pins and sense resistor network — the copper pad under the device must be soldered to a solid ground plane with thermal vias to prevent the junction temperature climbing above 105 °C at full current. Operating temperature is rated -40 °C to 105 °C ambient — this covers industrial enclosures and motor-drive cabinets, but the thermal resistance from junction to ambient depends almost entirely on board layout, not just the package rating. Surface-mount tape-and-reel packaging — confirm the paste volume and reflow profile with the assembly house; the exposed paddle on the 10-SMD requires a targeted thermal land pattern or the device will tombstone on large paste volumes.
