LM3677 Datasheet, PDF (1/30 Pages) Texas Instruments – 3MHz, 600mA Miniature Step-Down DC-DC Converter for Ultra Low Voltage Circuits

LM3677
www.ti.com
SNVS502E – MARCH 2007 – REVISED OCTOBER 2008
LM3677 3MHz, 600mA Miniature Step-Down DC-DC Converter for Ultra Low Voltage
Circuits
Check for Samples: LM3677
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 micro SMD package and
6-pin LLP 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
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.
The device offers superior features and performance for mobile phones and similar portable applications with
complex power management systems. Automatic intelligent switching between PWM low-noise and PFM low-
current mode offers improved system control. During PWM mode operation, the device operates at a fixed
frequency of 3 MHz (typ). PWM mode drives loads from ~ 80 mA to 600 mA max. Hysteretic PFM mode extends
the battery life by reducing the quiescent current to 16 µA (typ.) during light load and standby operation. Internal
synchronous rectification provides high efficiency. In shutdown mode (Enable pin pulled down), the device turns
off and reduces battery consumption to 0.01 µA (typ.).
The LM3677 is available in a lead-free (NOPB) 5-bump micro SMD package and 6-pin LLP package. A switching
frequency of 3 MHz (typ.) allows use of tiny surface-mount components. Only three external surface-mount
components, an inductor and two ceramic capacitors, are required.
1
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2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2007–2008, Texas Instruments Incorporated