The ISL9305 is an integrated mini Power Management IC

(mini-PMIC) ideal for applications of powering low-voltage

microprocessor or multiple voltage rails with battery as input

sources, such as a single Li-ion or Li-Polymer. ISL9305

integrates two high-efficiency 3MHz synchronous step-down

converters (DCD1 and DCD2) and two low-input, low-dropout

linear regulators (LDO1 and LDO2).

The 3MHz PWM switching frequency allows the use of very small

external inductors and capacitors. Both step-down converters can

enter skip mode under light load conditions to further improve the

efficiency and maximize the battery life. For noise sensitive

applications, they can also be programmed through I2C interface

to operate in forced PWM mode regardless of the load current

condition. The I2C interface supports on-the-fly slew rate control of

the output voltage from 0.825V to 3.6V at 25mV/step size for

dynamic power saving. Each step-down converter can supply up to

800mA load current. The default output voltage can be set from

0.8V to VIN using external feedback resistors on the adjustable

version, or the ISL9305 can be ordered in factory pre-set voltage

options from 0.9V to 3.6V in 50mV step.

The ISL9305 also provides two 300mA low dropout (LDO)

regulators. The input voltage range is 1.5V to 5.5V allowing

them to be powered from one of the on-chip step-down

converters or directly from the battery. The default LDO

power-up output comes with factory pre-set fixed output

voltage options between 0.9V to 3.3V.

The ISL9305 is available in a 4mmx4mm 16 Ld TQFN package.

Features

? Dual 800mA, Synchronous Step-down Converters and Dual

300mA, General-purpose LDOs

? Input Voltage Range

- DCD1/DCD2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3V to 5.5V

- LDO1/LDO2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5V to 5.5V

? 400kb/s I2C-bus Series Interface Transfers the Control Data

Between the Host Controller and the ISL9305

? Adjustable Output Voltage

- VODCD1/VODCD2 . . . . . . . . . . . . . . . . . . . . . . . . 0.8V to VIN

? Fixed Output I2C Programmability

- At 25mV/Step . . . . . . . . . . . . . . . . . . . . . . . . 0.825V to 3.6V

? LDO1/LDO2 Output Voltage I2C Programmability

- At 50mV/Step . . . . . . . . . . . . . . . . . . . . . . . . . . 0.9V to 3.6V

? 50μA IQ (Typ) with DCD1/DCD2 in Skip Mode; 20μA IQ (Typ)

for each Enabled LDO

? On-the-fly I2C Programming of DC/DC and LDO Output

Voltages

? DCD1/DCD2 I2C Programmable Skip Mode Under Light

Load or Forced Fixed Switching Frequency PWM Mode

? Small, Thin, 4mmx4mm TQFN Package

Applications

? Cellular Phones, Smart Phones

? PDAs, Portable Media Players, Portable Instruments

? Single Li-ion/Li-Polymer Battery-Powered Equipment

? DSP Core Power