Automotive-grade buck regulator delivers 3A

January 07, 2015 // By Graham Prophet
This 3.0A device features low input-voltage dropout and enhanced idle/stop/start recovery operation; the A8590 buck regulator joins Allegro MicroSystems’ range of automotive-grade AEC-Q100 qualified regulator ICs.

The device has been designed to provide the power-supply requirements of next-generation car audio and infotainment systems, and provides all the control and protection circuitry for a 3A regulator which will withstand the rigours of a wide automotive battery input voltage range. The A8590 can also be used in cluster and centre stack applications and in advanced driving assistance systems.

The device employs pulse frequency modulation to draw less than 50 μA from a 12V input while supplying a 3.3V/40 μA output. After startup, the A8590 operates down to an input voltage (falling) of at least 3.6V, and maintains ±1% output voltage accuracy.

Other features of the A8590 include PWM/PFM mode control and the ability to synchronise PWM frequency to an external clock. It also has a “sleep” pin for an ultra-low current shutdown mode.

The device has external compensation to accommodate a wide range of frequencies and external components, and provides a power-on reset signal validated by the output voltage. Extensive protection features include pulse-by-pulse current limit, “hiccup mode” short-circuit protection, open/short asynchronous diode protection, boot open/short voltage protection, input-voltage undervoltage lockout, output-voltage overvoltage protection, and thermal shutdown.

The A8590KLPTR-T is supplied in a low profile 16-pin TSSOP package with exposed power pad. It is lead (Pb) free, with 100% matt-tin leadframe plating;