The ISL9443 is a triple-output synchronous buck controller that

integrates three PWM controllers which are fully featured and

designed to provide multi-rail power for use in products such as

cable and satellite set-top boxes, VoIP gateways, cable modems,

and other home connectivity products as well as a variety of

industrial and general purpose applications. Each output is

adjustable down to 0.7V. The PWMs are synchronized at 180°

out-of-phase, thus reducing the input RMS current and ripple

voltage.

The ISL9443 offers programmable soft-start and tracking

functions for ease of supply rail sequencing and integrated

UV/OV/OC/OT protections in a space conscious 5mmx5mm QFN

package.

Switching frequency can be set between 200kHz and 1200kHz

using a resistor. The ISL9443 can be synchronized to an external

clock to reduce beat frequencies.

The ISL9443 utilizes internal loop compensation to keep

minimum peripheral components for a compact design and a

low total solution cost. The controller is implemented with

current mode control with feed forward to cover various

applications even with fixed internal compensation.

Features

? Three Integrated Synchronous Buck PWM Controllers

- Internal Bootstrap Diodes

- Independent Programmable Output Voltage

- Independent Soft-Starting and Tracking

? Power-Good Indicator

? Light Load Efficiency Enhancement

- Low Ripple Diode Emulation Mode with Pulse Skipping

? Supports Pre-Biased Output

? Programmable Frequency: 200kHz to 1200kHz

? Adaptive Shoot-Through Protection

? Out-of-Phase Switching (0°/180°/0°)

? No External Current Sense Resistor

- Uses Lower MOSFET’s rDS(ON)

? Complete Protection

- Overcurrent, Overvoltage, Over-Temperature

? Wide Input Voltage Range: 4.5V to 28V

? Pb-Free (RoHS Compliant)

Applications

? VoX Gateway Devices

? NAS/SAN Devices

? ATX power supplies