The A8591 buck regulator from Allegro MicroSystems, LLC contains all the control and protection circuitry to produce a 2 A regulator with ±1 percent output voltage accuracy. The A8591 employs pulse-frequency modulation (PFM) to draw less than 33 μA from 12 V input while supplying 5 V/40 μA output, suiting it for automotive battery-powered “keepalive” applications.
Allegro Microsystems’ A8591 buck regulator (Image courtesy of Allegro Microsystems).
The Sleep feature drops standby current down to 5 μA. When operational, the A8591 operates down to at least 3.6 V input to accommodate idle-stop battery input requirements. The regulator’s PWM switching frequency can be set between 300 kHz and 2.4 MHz and dithered, or synchronized to an external clock. It has extensive protection features including pulse-by-pulse current limit, hiccup mode short-circuit protection, open/short asynchronous diode protection, BOOT open/short voltage protection, VIN undervoltage lockout, NPOR, and thermal shutdown.
The regulator targets automotive and industrial markets, including applications such as infotainment, center stack and instrument clusters, advanced driver assistance systems (ADAS), heads-up display (HUD), and HVAC systems and industrial controls.
The part is supplied in a 3 mm × 3 mm 10-pin wettable flank DFN package (suffix EJ) with exposed power pad for enhanced thermal dissipation. List price is $1.54 each in quantities of 1,000.
