FEATURES

• Optimized for Low Voltage Applications

• 2.6-to-7V Operating Input Range

• 8V Max Input Blocking Voltage

• Adjustable In-rush Current Control

• Configurable Input Power Failure Level

• Programmable up to 6A Input Current Limit

• Programmable 5V to 28V Boost Storage Voltage

• 28V@4A Synchronous Buck Supports 100%

Duty Cycle

• Programmable up to 2.25MHz Buck Operating

Frequency for Small Inductor Size

• Power Loss, Vout Power Good, and Storage Cap

Power Good Indicators

• Compatible with Different Types of Storage Caps:

Super Caps, Electrolytic, Tantalum, POSCAP etc.

• Autonomous Health Monitoring for Detection of

Earlier Storage Capacitor Failures

• Configurable Interrupts to Inform Host for any

Faults/Status Change

• eFuse, Boost, and Buck UV/OV/OC Protection

• Thermal Alert and Protection

• Thermal Enhanced FCQFN 4x4-32 package

APPLICATIONS

• Solid State Drives

• Power Backup Systems

• Industrial Applications

• eFuse

• Hot Plug Devices

GENERAL DESCRIPTION

The ACT4921 device is a highly integrated power loss

protection IC. It provides backup storage power in the

event of an input power failure. A built-in boost converter

provides high voltage energy storage to minimize

storage capacitor size requirements. The built-in buck

converter regulates the storage voltage to a fixed output

voltage. It contains internal, back-to-back eFuse FETs

to provide bi-directional input to output isolation. The IC

also provides hot swap and inrush current control.

The ACT4921 is very flexible and can easily be

configured with I2C and external components. It

features programmable storage capacitor voltage to

optimize the storage capacitor sizing and system run

time. The internal health monitoring provide an extra

layer of protection and improve system reliability and

early capacitor failure notification. It automatically

checks the storage capacitor health and notifies the

user when the energy in the storage caps is not

sufficient for backup power. The built-in synchronous

buck converter maximizes energy transfer from the

storage caps to the system.

ACT4921 provides an I2C bus interface to allow MCU

control and monitoring. There are supervisor monitors

for the input voltage, output voltage, and storage

voltage. It is available with the thermal enhanced QFN

4x4 32 pin package.