GENERAL DESCRIPTION

The ADP2105/ADP2106/ADP2107 are low quiescent current, synchronous, step-down dc-to-dc converters in a compact 4 mm × 4 mm LFCSP package. At medium to high load currents, these devices use a current mode, constant frequency pulse-width modulation (PWM) control scheme for excellent stability and transient response. To ensure the longest battery life in portable applications, the ADP2105/ADP2106/ADP2107 use a pulse frequency modulation (PFM) control scheme under light load conditions that reduces switching frequency to save power.

FEATURES

Extremely high 97 efficiency

Ultralow quiescent current: 20 μA

1.2 MHz switching frequency

0.1 μA shutdown supply current

Maximum load current

ADP2105: 1 A

ADP2106: 1.5 A

ADP2107: 2 A

Input voltage: 2.7 V to 5.5 V

Output voltage: 0.8 V to VIN

Maximum duty cycle: 100

Smoothly transitions into low dropout (LDO) mode

Internal synchronous rectifier

Small 16-lead 4 mm × 4 mm LFCSP package

Optimized for small ceramic output capacitors

Enable/shutdown logic input

Undervoltage lockout

Soft start

Supported by ADIsimPower™ design tool

APPLICATIONS

Mobile handsets

PDAs and palmtop computers

Telecommunication/networking equipment

Set top boxes

Audio/video consumer electronics