Texas Instruments LM3677
The LM3677 step-down DC-DC converter is optimized for powering ultra-low voltage circuits from a single Li-Ion cell battery and input voltage rails from 2.7V to 5.5V. It provides up to 600 mA load current over the entire input voltage range. The LM3677 is configured to different fixed voltage output options as well as an adjustable output voltage version range from 1.2V to 3.3V.FEATURES
1●2 16 µA typical quiescent current
● 600 mA maximum load capability
● 3 MHz PWM fixed switching frequency (typ.)
● Automatic PFM/PWM mode switching
● Available in 5-bump DSBGA package and 6-pin USON package
● Internal synchronous rectification for high efficiency
● Internal soft start
● 0.01 µA typical shutdown current
● Operates from a single Li-Ion cell battery
● Only three tiny surface-mount external components required (solution size less than 20 mm2)
● Current overload and thermal shutdown protection
APPLICATIONS
● Mobile Phones● PDAs
● MP3 Players
● W-LAN
● Portable Instruments
● Digital Still Cameras
● Portable Hard Disk Drives
DESCRIPTION
TYPICAL APPLICATION CIRCUITS VIN 2.7V to 5.5V CIN 4.7 PF VIN 1 5 LM3677 GND 2 L1: 1.0 PH SW EN 3 FB 4 VOUT COUT 10 PF Figure 1. Typical Application Circuit VIN 2.7V to 5.5V CIN 4.7 PF VIN GND 15 LM3677ADJ 2 L1: 1.0 PH SW C1 EN 3 4 FB C2 VOUT R1 COUT 10 PF R2 Figure 2. Typical Application Circuit - ADJ. Version Figure 3. Efficiency vs.