Intersil's ISL78233 and ISL78234 are highly efficient, monolithic, synchronous step-down DC/DC converters that can deliver 3 A (ISL78233), 4 A (ISL78234), and 5 A (ISL7835) of continuous output current from a 2.7 V to 5.5 V input supply. The devices use current mode control architecture to deliver a very low duty cycle operation at high frequency with fast transient response and excellent loop stability. The ISL78233 and ISL78234 integrate a very low ON-resistance P-channel (35 mΩ) high-side FET and N-channel (11 mΩ) low-side FET to maximize efficiency and minimize external component count. The 100% duty-cycle operation allows less than 200 mV dropout voltage at 4 A output current. The operation frequency of the pulse width modulator (PWM) is adjustable from 500 kHz to 4 MHz. The default switching frequency of 2 MHz is set by connecting the FS pin high. The ISL78233, ISL78234, and ISL78235 can be configured for discontinuous or forced continuous operation at light load. Forced continuous operation reduces noise and RF interference, while discontinuous mode provides higher efficiency by reducing switching losses at light loads.

Intersil ISL7823xEVAL2z User Guide