Overview: Triple, 180° Out-of-Phase, Synchronous Step-Down PWM Controller
ISL9443
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 pensation to keep minimum peripheral ponents for a pact 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 pensation.
