ALLEGRO ACS720KLATR-65AB-T

The ACS720 is a Hall-effect-based high-precision current sensor IC with multiple programmable fault levels, designed for industrial and consumer applications — with a particular focus on motor control and power inverter-level applications.

One of the key advantages of the ACS720 is its proprietary IC SOIC16W package, which delivers high isolation while reducing the bill of materials. The ACS720 operates from a single 5V supply, with an output voltage swing of 0 to 3V and a zero-current output stabilized at 1.5V. This allows the ACS720 to operate from a 5V supply while its output remains compatible with the 3.3V ADCs commonly found on many MCUs. In addition, the ACS720's high power supply rejection ratio (PSRR) suppresses noise typically present in the PCB or system power section, maintaining high accuracy in noisy environments.

The device features dual fault functionality that is user-configurable. Fast and slow fault outputs enable short-circuit and overcurrent fault detection. Fault levels are set by the user via a resistor divider on the ACS720 supply. The fault outputs are open-drain, allowing users to pull them up to an MCU-compatible voltage. The open-drain outputs also enable simple logic-OR operation across multiple sensor fault outputs.

The ACS720 also integrates differential current sensing to reject external magnetic fields, greatly simplifying board layout in three-phase motor applications.

Thanks to Allegro's patented digital temperature compensation technology, this open-loop sensor achieves near-closed-loop accuracy — ultimately offering a smaller, more cost-effective solution for many current sensing applications that have traditionally relied on closed-loop core-based sensors.

The ACS720 comes in a compact SMT SOIC16 package. The lead frame is plated with 100% matte tin, compatible with standard lead-free (Pb) PCB assembly processes. Internally, the device is lead-free except for the flip-chip high-temperature lead-containing solder bumps (currently compliant with RoHS exemptions). The device is fully calibrated prior to shipment.

• Differential current sensing eliminates common-mode fields, simplifying PCB layout
• Two user-settable fault functions for fast short-circuit protection and slow overcurrent detection
• Industry-leading noise performance and significantly improved bandwidth via proprietary amplifier and filter design techniques
• Patented integrated digital temperature compensation circuit maintains high open-loop sensor accuracy across temperatures
• 1.0mΩ primary conductor resistance for low power dissipation and high surge current capability
• Compact, low-profile SOIC16 package for space-constrained applications
• Integrated shield nearly eliminates capacitive coupling between current conductor and die due to high dV/dt voltage transients
• 5V single-supply operation with 0 - 3V output swing
• Output voltage proportional to AC or DC current
• Factory-trimmed sensitivity and quiescent output voltage for improved accuracy
• UL60950-1 certified with 3600Vrms dielectric withstand voltage
• High power supply rejection ratio for noisy environments