ISL9109
RF PA 1.5A DC/DC Regulator
Key Features
- Integrated Synchronous Buck Regulator with up to 95% Efficiency
- 2.7V to 5.5V Supply Voltage
- 1.5A Output Current
- 4.3µA Quiescent Supply Current in Standby Mode
- 22µA Quiescent Supply Current in Skip (Low IQ) Mode
- 3% Output Accuracy Over Temperature/Load/Line
- Selectable Forced PWM Mode or Skip Mode
- Less Than 1µA Logic Controlled Shutdown Current
- 100% Maximum Duty Cycle for Lowest Dropout
- Soft-Start
- Peak Current Limiting, Short Circuit Protection
- Over-Temperature Protection
- 8 Ld 2mmx3mm DFN
- Pb-Free (RoHS Compliant)
Description
ISL9109 is 1.6MHz synchronous step-down regulator with integrated power switches capable of delivering 1.5A output for powering RF Power Amplifiers in cellular phones. The ISL9109 features a standby mode which allows for rapid startup while prolonging battery life. The supply voltage range is from 2.7V to 5.5V allowing 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. It has a flexible operation mode selection of forced PWM mode and Skip (Low IQ) mode with typical 22µA quiescent current for highest light load efficiency to maximize battery life.
The ISL9109 integrates a pair of low ON-resistance P-Channel and N-Channel MOSFETs to maximize efficiency and minimize external component count.
When in standby, the ISL9109 band-gap reference is powered. This assists in a rapid power-up when the EN pin is asserted high. Other features include soft-start, overcurrent protection, and thermal shutdown.
The ISL9109 is offered in 8 Ld 2mmx3mm DFN package with 0.9mm typical height. The complete converter can occupy less than 1cm2 area.
Applications
- Single Li-Ion Battery-Powered Equipment
- RF Power Amplifier
- CPU Power
- PDAs and Palmtops
