The ADP2105 / ADP2106 / ADP2107ACPZ-R7 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, thesedevices use a current mode, constant frequency pulse-widthmodulation (PWM) control scheme for excellent stability andtransient response. To ensure the longest battery life in portableapplications, the ADP2105 / ADP2106 / ADP2107ACPZ-R7 use a pulsefrequency modulation (PFM) control scheme under light loadconditions that reduces switching frequency to save power.
The ADP2105 / ADP2106 / ADP2107ACPZ-R7 run from input voltages of2.7 V to 5.5 V, allowing single Li+/Li− polymer cell, multiplealkaline/NiMH cells, PCMCIA, and other standard power sources.The output voltage of ADP2105 / ADP2106 / ADP2107ACPZ-R7 is adjustablefrom 0.8 V to the input voltage (indicated by ADJ), whereas theADP2105 / ADP2106 / ADP2107ACPZ-R7 are available in preset outputvoltage options of 3.3 V, 1.8 V, 1.5 V, and 1.2 V (indicated by x.x V).Each of these variations is available in three maximum currentlevels: 1 A (ADP2105), 1.5 A (ADP2106), and 2 A (ADP2107).The power switch and synchronous rectifier are integrated forminimal external part count and high efficiency. During logiccontrolled shutdown, the input is disconnected from the output,and it draws less than 0.1 µA from the input source. Other keyfeatures include undervoltage lockout to prevent deep batterydischarge and programmable soft start to limit inrush current atstartup.
Feature
- Extremely high 97% efficiency
- Ultralow quiescent current: 20 μA
- 1.2 MHz switching frequency
- 0.1 μA shutdown supply current
- Maximum load current: 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
(Picture: Pinout)