August 11, 2015
Worcester, MA – Allegro MicroSystems, LLC expands its automotive regulator portfolio by adding two devices targeted specifically at USB power applications. Allegro’s A8652 and A8653 devices are high output current synchronous buck regulator ICs that provide tight load regulation over a wiring harness without the need for remote sense lines. This remote load regulation is achieved with an integrated open-loop correction scheme that, given a known wiring harness resistance, adjusts the output voltage based on the measured load current and a user programmable gain, achieving ±2% accuracy at 500 mV of correction. The Remote Load Regulation control includes a 115% regulated voltage clamp in conjunction with a dynamic over voltage protection with OVP threshold changing with the correction voltage.
The A8652/53 devices include a user configurable load side current limit to fold back the output voltage during an output over current condition. The devices regulate nominal input voltages from 4.0 V to 36 V and remain operational when VIN drops as low as 2.6 V. When the input voltage approaches the output voltage, the duty cycle is maximized to maintain the output voltage. Key features include externally set soft-start time, external compensation network for power train optimization, an EN input to enable VOUT, a SYNC/FSET input to synchronize or set the PWM switching frequency, and a PowerOK output to indicate when VOUT is within regulation. Protection features include VIN under-voltage-lockout, cycle-by-cycle current limit, hiccup mode short-circuit protection, dynamic over-voltage protection, and thermal shutdown. Both devices provide open-circuited, adjacent pin short-circuit, and short-to-ground protection at every pin to satisfy the most demanding automotive and non-automotive applications.
The A8652/53 devices are available in a 16-pin eTSSOP package with exposed pad for enhanced thermal dissipation. The package is lead (Pb) free, with 100% matte tin lead frame plating. The maximum junction temperature (TJ (max)) is 150°C.