AIC1531

Features:

Continuous 3.3V Output from Three Inputs.

Complete Power Management Solution.

VCC, VSBY Regulator Supplies 500mA Output.

Built-in Hysteresis When Selecting Input Supplies.

Integrated Switch has Very Low RDS(ON) 120mOhm (typ.).

Integrated Switch Supplies 500mA From VAUX .

Output can be Forced Higher than Input (Off-State).

Application

Desktop Computers.

PCI Adapter Cards with Wake-On-LAN.

Network Interface Cards (NICs).

Multi Power System.

System with Standby Capabilities.

Pinout

Description

AIC1531 is a dual input regulator with VAUX switch capable of delivering 3.3V/500mA continuously. The output power is provided from three independent input voltage sources on a prioritized basis. Power is always taken in priority using the following order VCC, VSBY, and VAUX .
The AIC1531 meets Intels " Instantly Available " power requirements which follows the "Advanced Configuration and Power Interface" (ACPI) standards. When either VCC or VSBY is present, the device automatically enables the regulator and produces a stable 3.3V output VOUT. When only VAUX (3.3V) is present, the device provides a low impedance direct connection (120mOhm typ.) from VAUX to VOUT.
The AIC1531 also prevents excessive current from flowing VOUT to either input voltage or ground when the output voltage is higher than the input voltage. All the necessary control circuitry needed to provide a smooth and automatic transition between all the three supplies has been incorporated. This allows both VCC and VSBY to be dynamically switched without loss of output voltage.