- Design Center
- About Allegro
September 20, 2016
Allegro MicroSystems, LLC announces a new power management IC that 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 5 V, 75 mAMAX high-voltage protected LDO for remote sensors (V5P), and a 0.8 to 3.3 V, 800 mAMAX adjustable synchronous buck regulator (ADJ). Designed to supply microprocessor power supplies in high-temperature environments, 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 2 ms 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 2 ms (WDADJ). 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 (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 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, 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, 5 mm × 5 mm, 0.5 mm pitch QFN package (suffix “ET”) with exposed thermal pad.
Allegro MicroSystems is redefining the future of power and sensing technologies. From green energy to advanced mobility and motion control systems, our team is passionate about developing intelligent solutions that move the world forward and give our customers a competitive edge. With global engineering, manufacturing and support, Allegro is a trusted partner to both large enterprises and regional market leaders worldwide. Visit www.allegromicro.com.