Allegro MicroSystems — ACS37030/2 High-Accuracy Current Sensor

Allegro MicroSystems ACS37030/2 High-Accuracy Current Sensor

With Reference or Fault Output

Allego MicroSystems' ACS37030/2 is a fully integrated current sensor IC that senses current flowing through the primary conductor. Two signal paths are used: a Hall-effect element path to capture DC and low-frequency current information, and an inductive coil path to capture high-frequency current information. These two paths are summed to allow for sensing of a wide frequency band with a single device. The properties of the coil increase SNR as frequency increases, minimizing noise seen at the output.

The internal construction provides high isolation by magnetically coupling the field generated by current flow in the conductor to the fully monolithic Hall and coil IC. The current is sensed differentially by two Hall plates and two coils that subtract out interfering common-mode magnetic fields. The IC has no physical connection to the integrated current conductor and provides a 3500 VRMS isolation voltage between the primary and secondary signal leads of the package. This high rating provides a basic working voltage of 840 VRMS. Both zero current reference (ACS37030) and overcurrent fault with internal pull up (ACS37032) options are available.

The ACS37030/32 is provided in a six-lead custom SOIC surface mount package with the current conductor leads formed together for a reduced resistance of 0.6 mΩ. The leadframe is plated with 100% matte tin, which is compatible with standard lead (Pb) free printed circuit board assembly processes. Internally, the device is Pb-free.

Functional Block Diagram

Typical Application Circuit

Packaging

The ACS37030 and the ACS37032 are offered in two fused-lead SOIC-6 package options. The LZ package has a lower conductor resistance versus standard SOIC-8 packages and supports higher isolation of up to 840VRMS basic isolation or 420VRMS reinforced isolation. The MY package is a widebody SOIC-6 package that supports a similar reinforced isolation rating to comparable SOICW-16 packages in just half the size.

Evaluation Board - ACSEVB-LC8-LZ6

Enhanced thermal performance 6-layer PCB with 2 oz copper weight on all layers Nonconductive-filled via-in-pad High-performance FR4 material with 180°C glass transition temperature Flexible layout for user installed connection points Standard Keystone test points SMA/SMB connector 2-pin headers Integrated current-loop resistance can be measured directly on the evaluation board after test-point installation; voltage drop can be measured for approximating power loss in the package.