The A4413 supplies both a 5V, 75mAMAX high-voltage protected LDO for remote sensors (V5P).
Designed to supply microprocessor power supplies in high-temperature environments, Allegro MicroSystems' new power management IC can be configured as a buck or buck-boost pre-regulator to efficiently convert automotive battery voltages into a tightly regulated intermediate voltage complete with control, diagnostics, and protections.
The output of Allegro’s A4413 supplies both a 5V, 75mAMAX high-voltage protected LDO for remote sensors (V5P), and a 0.8 to 3.3V, 800mAMAX adjustable synchronous buck regulator (ADJ). The A4413 is ideal for under hood and other automotive applications.
The A4413 can be enabled by its logic-level (ENB) or high-voltage (ENBAT) input. Diagnostic outputs from the A4413 include a power-on-reset output (NPOR) with a 2ms rising delay to monitor the synchronous buck, a PowerOK output to monitor the 5 V LDO (POK5V), and an ENBAT status output (ENBATS). Dual bandgaps—one for regulation and one for fault detection—improve long-term reliability of the A4413.
The A4413 contains a pulse-width window watchdog (PWWD) timer that can be programmed to detect pulse widths from 1 to 2ms (WDADJ). The watchdog timer has an activation delay that scales with the pulse-width setting to accommodate processor start up. 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 (WDENn) 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 5V output is protected from a short-to-battery event. Both switching regulators include pulse-by-pulse current limit, hiccup mode short-circuit protection, LX (regulator output switching node) short-circuit protection to provide protection to the IC from damage in the case of accidental short-circuit from LX pins, missing asynchronous diode protection (VREG only), and thermal shutdown (TSD).
The A4413 is supplied in a low-profile 32-lead, 5mm × 5mm, 0.5mm pitch QFN package (suffix “ET”) with exposed thermal pad.