ISL9107 and ISL9108 are 1.6MHz synchronous step-down regulators with integrated power switches capable of delivering 1.5A output current, which is ideal for powering low-voltage microprocessors in compact devices such as PDAs and cellular phones. These devices are optimized for generating low output voltages down to 0.8V. The supply voltage range is from 2.7V to 5.5V allowing for the use of a single Li+ cell, three NiMH cells or a regulated 5V input. 1.6MHz pulse-width modulation (PWM) switching frequency allows using small external components. They have flexible operation mode selection of forced PWM mode and Skip (Low I_Q) mode with typical 17μA quiescent current for highest light load efficiency to maximize battery life.

The ISL9107 and ISL9108 integrate a pair of low ON-resistance P-Channel and N-Channel MOSFETs to maximize efficiency and minimize external component count.

The ISL9107 offers a typical 215ms Power-Good (PG) timer when powered up. The timer output can be reset by RSI. When shutdown, ISL9107 and ISL9108 discharge the output capacitor. Other features include internal digital soft-start, enable for power sequence, overcurrent protection, and thermal shutdown.

The ISL9107 and ISL9108 are offered in 8 Ld 2mmx3mm DFN package with 0.9mm typical height. The complete converter can occupy less than 1cm² area.

• Integrated Synchronous Buck Regulator with up to 95% Efficiency
• 2.7V to 5.5V Supply Voltage
• 1.5A Guaranteed Output Current
• 17μA Quiescent Supply Current in Skip (Low I_Q) Mode
• Selectable Forced PWM Mode and Skip Mode
• Less Than 1μA Logic Controlled Shutdown Current
• 100% Maximum Duty Cycle for Lowest Dropout
• Discharge Output Capacitor when Shutdown
• Internal Digital Soft-Start
• Enable, Peak Current Limiting, Short Circuit Protection
• Over-Temperature Protection
• Power-Good Function (for ISL9107 only)
• 8 Ld 2mmx3mm DFN
• Pb-Free (RoHS Compliant)

• Single Li-Ion Battery-Powered Equipment
• DSP Core Power
• PDAs and Palmtops