LM3671 Datasheet | National Semiconductor

LM3671 2MHz , 600m A Step-Down DC-DC Converter in SOT23-5 November 2004 LM3671 2MHz , 600m A Step-Down DC-DC Converter in SOT23-5 General Description The LM3671 step-down DC-DC converter is optimized for powering ultra-low voltage circuits from a single Li-Ion cell or 3 cell Ni MH/Ni Cd batteries. It provides up to 600m A load current, over an input voltage range from 2.8V to 5.5V. There are several different fixed voltage output options available as well as an adjustable output voltage version. The device offers superior Features and performance for mobile phones and similar portable applications with plex power management systems. Automatic intelligent switching between PWM low-noise and PFM low-current mode offers improved system control. During full-power operation, a fixed-frequency 2 MHz (typ). PWM mode drives loads from ∼70 m A to 600 m A max. Hysteretic PFM mode extends the battery life through reduction of the quiescent current to 16 µA (typ) at light loads and system standby. Internal synchronous rectification provides high efficiency. In shutdown mode (Enable pin pulled low) the device turns off and reduces battery consumption to 0.01 µA (typ). The LM3671 is available in a SOT23-5 package with Pb and No Pb (Lead free) versions. A high switching frequency - 2 MHz (typ) - allows use of tiny surface-mount ponents. Only three external surface-mount ponents, an inductor and two ceramic capacitors, are required. 2 MHz PWM fixed switching frequency (typ) Automatic PFM/PWM mode switching Available in fixed output voltages and adjustable version SOT23-5 package Internal synchronous rectification for high efficiency Internal soft start 0.01 µA typical shutdown current Operates from a single Li-Ion cell or 3 cell Ni MH/Ni Cd batteries n Only three tiny surface-mount external ponents required (one inductor, two ceramic capacitors) n Current overload and Thermal shutdown protection n n n n n n n n Applications n n n n n n n Mobile phones PDAs MP3 players W-LAN...