ISL8024A

The ISL8024A is a highly efficient, monolithic, synchronous step-down DC/DC converter that can deliver 4A of continuous output current from a 2.7V to 5.5V input supply. The device uses current mode control architecture to deliver very low-duty cycle operation at high frequency with fast transient response and excellent loop stability. It has an adjustable frequency from 500kHz to 4MHz with the default at 2MHz (ISL8023A/24A).

The ISL8024 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 200mV dropout voltage at 4A output current. The operation frequency of the pulse-width modulator (PWM) is adjustable from 500kHz to 4MHz. The default switching frequency of 1MHz is set by connecting the FS pin high, which allows for the use of small external components.

The ISL8024 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.

Fault protection is provided by internal hiccup mode current limiting during short circuit and overcurrent conditions. Other protection, such as overvoltage and over-temperature are also integrated into the device. A power-good output voltage monitor indicates when the output is in regulation.

The ISL8024 offers a 1ms power-good (PG) timer at power-up. When in shutdown, the device discharges the output capacitor through an internal soft-stop switch. Other features include internal fixed or adjustable soft-start and internal/external compensation. The device is offered in a space-saving 16 Ld 3mm x 3mm Pb-free QFN package with an exposed pad for improved thermal performance and 1mm maximum height. The complete converter occupies less than 0.22 in² area.

Various fixed output voltages are available upon request. See the datasheet for more details.