Allegro MicroSystems announces the A4413 PMIC that can be configured as a buck or buck-boost pre-regulator to convert automotive battery voltages into a regulated intermediate voltage with control, diagnostics, and protections. The output supplies both a 5 V, 75 mAmax high-voltage protected LDO for remote sensors, and a 0.8 to 3.3 V, 800 mAmax adjustable synchronous buck regulator. Designed to supply microprocessor power supplies in high-temperature environments, the A4413 suits under hood and other automotive applications.
The A4413 can be enabled by its logic-level (ENB) or high-voltage (ENBAT) input. Diagnostic outputs include a power-on-reset output (NPOR) with a 2 ms rising delay to monitor the synchronous buck, a PowerOK output to monitor the 5 V LDO, and an ENBAT status output.
The A4413 contains a pulse-width window watchdog timer to detect pulse widths from 1 to 2 ms. The watchdog timer has an activation delay that scales with the pulse-width setting to accommodate processor startup. The tolerance of the watchdog’s window can be set to ±8%, ±13%, or ±18% using the WDTOL pin. The watchdog timer has an active-low enable pin to facilitate initial factory programming or field reflash programming.
Protection features include under- and overvoltage lockout on both output supply rails. In case of a shorted output, the LDO regulator features foldback overcurrent protection. In addition, the 5 V output is protected from a short-to-battery event. Both switching regulators include pulse-by-pulse current limit, hiccup mode short-circuit protection, regulator output switching node short-circuit protection, missing asynchronous diode protection, and thermal shutdown. The A4413 is supplied in a low-profile 32-lead, 5 mm × 5 mm, 0.5 mm pitch QFN package with exposed thermal pad. It is priced at $2.24 in quantities of 1,000. Allegro MicroSystems: www.allegromicro.com