GENERAL DESCRIPTION
The ADP3309 is a member of the ADP330x family of precision low dropout anyCAP voltage regulators. It is pin-for-pin and functionally compatible with National’s LP2981, but offers performance advantages. The ADP3309 stands out from conventional LDOs with a novel architecture and an enhanced process. Its patented design requires only a 0.47 μF output capacitor for stability. This device is stable with any type of capacitor regardless of its equivalent series resistance (ESR) value, including ceramic types for space restricted applications.
The ADP3309 achieves ±1.2% accuracy at room temperature and ±2.2% overall accuracy over temperature, line, and load regulations. The dropout voltage of the ADP3309 is only 120 mV (typical) at 100 mA. This device also includes a current limit and a shutdown feature. In shutdown mode, the ground current is reduced to ~1 μA.
The ADP3309 operates with a wide input voltage range from 2.8 V to 12 V and delivers a load current in excess of 100 mA. The ADP3309 anyCAP LDO offers a wide range of output voltages.

  FEATURES
  ±1.2% accuracy over line and load regulations @ 25°C
  Ultralow dropout voltage: 120 mV typical @ 100 mA
  Requires only COUT = 0.47 μF for stability
  anyCAP LDOs are stable with all types of capacitors (including MLCC)
  Current and thermal limiting
  Low noise
  Low shutdown current: 1 μA
  2.8 V to 12 V supply range
  −20°C to +85°C ambient temperature range
  Several fixed voltage options
  Ultrasmall 5-lead SOT-23 package
  Excellent line and load regulations
 
APPLICATIONS
  Cellular telephones
  Notebook, palmtop computers
  Battery-powered systems
  PCMCIA regulator
  Bar code scanners
  Camcorders, cameras