The new ACS760 from Allegro MicroSystems Europe is a hot-swap protection IC designed for 12 V high-side applications.
The new device combines Allegro's Hall-effect current sensing technology with hot-swap control circuitry, resulting in a highly efficient integrated controller. No external sense resistor is required, resulting in greatly
reduced I2R losses in the power path.
The ACS760 incorporates an external high-side FET gate drive, and produces an analogue output voltage (factory trimmed for gain and offset) which is proportional to the current sensed in the device lead-frame. The soft-start/hot-swap function is accessed via the logic 'enable' input pin and an optional user-defined soft-start capacitor.
When the ACS760 is externally enabled and the voltage rail is above the internal undervoltage lockout threshold, the internal charge pump drives the gate of the external FET. When a fault is detected, the gate is disabled while simultaneously alerting the application that a fault has occurred.
Three levels of fault protection are integrated within the ACS760: 240 VA power fault protection with user-programmable delay; user-programmable overcurrent fault threshold with programmable delay; and short-circuit protection, which disables the gate in less then 2 µs.
In the event of the external high-side FET failing in a short-circuit condition, the ACS760 detects the failure, immediately disables the gate, and alerts the host system.
The IC is designed for single-supply operation from 10.8 to 13.2 V, and has 1.5 milliohm internal conductor resistance. It is protected against electrostatic discharge at up to 2 kV for all pins.
The ACS760 is supplied in a 24-lead QSOP package (suffix LF) which is lead-free and RoHS compliant, and the operating temperature range is -40°C to +85°C.