The ISL8025, ISL8025A are highly efficient, monolithic, synchronous step-down DC/DC converters that can deliver 5A of continuous output current from a 2.7V to 5.5V 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 ISL8025, ISL8025A integrates a very low ON-resistance P-Channel (45mΩ) high-side FET and N-Channel (19mΩ) low-side FET to maximize efficiency and minimize external component count. The 100 duty-cycle operation allows less than 225mV dropout voltage at 5A output current. The operation frequency of the pulse-width modulator (PWM) is adjustable from 500kHz to 4MHz. The default switching frequency, which is set by connecting the FS pin high, is 1MHz for the ISL8025 and 2MHz for the ISL8025A.

The ISL8025, ISL8025A 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.

Features

• 2.7V to 5.5V input voltage range

• Very low ON-resistance FET’s - P-channel 45mΩ and N-channel 19mΩ typical values

• High efficiency synchronous buck regulator with up to 95 efficiency

• Pin-to-pin compatible with ISL8023 and ISL8024

• 0.8 reference accuracy over-temperature/load/line

• Complete BOM with as few as 3 external parts

• Internal soft-start: 1ms or adjustable

• Soft-stop output discharge during disable

• Adjustable frequency from 500kHz to 4MHz - default at 1MHz (ISL8025), 2MHz (ISL8025A)

• External synchronization up to 4MHz

• Over-temperature, overcurrent, overvoltage and negative overcurrent protection

Applications

• DC/DC POL modules

• μC/µP, FPGA and DSP power

• Plug-in DC/DC modules for routers and switchers

• Portable instruments

• Test and measurement systems

• Li-ion battery powered devices