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