ISL8009A

The ISL8009A is a high efficiency, monolithic, synchronous step-down DC/DC regulator that can deliver up to 1. 5A continuous output current. It is optimized for generating low output voltages down to 0. 8V. The supply voltage range of 2. 7V to 5. 5V allows for the use of single Li+cell, three NiMH cells or a regulated 5V input. The ISL8009A 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 flexible operation mode selection of forced PWM mode and automatic PFM/PWM with as low as 17µA quiescent current, achieving high power conversion efficiency under light load condition, hence maximizing battery life. High 1. 6MHz pulse-width modulation (PWM) switching frequency allows the use of small external components. The ISL8009A integrates a pair of low ON-resistance P-Channel and N-Channel internal MOSFETs to maximize efficiency and minimize external component count. The 100% duty-cycle operation allows less than 400mV dropout voltage at 1. 5A output current. The ISL8009A offers a 2ms Power-On-Reset (POR) timer at power-up. The timer output can be reset by RSI. When shutdown, ISL8009A discharges the output capacitor through a 100Ω resistor. Other features include internal digital soft-start, enable for power sequence, overcurrent protection, and thermal shutdown. The ISL8009A is offered in a 2mmx3mm 8 Ld DFN package with 1mm maximum height. The complete converter occupies less than 1cm² area.