The LM3674 step-down DC-DC converter is optimized for powering low-voltage circuits from a single Li-Ion cell battery and input voltage rails from 2.7 V to 5.5 V. It provides up to 600-mA load current over the entire input voltage range. There are several fixed output voltages and adjustable output voltage versions.
The device offers superior features and performance for mobile phones and similar portable systems. During the Pulse Width Modulation (PWM) mode, the device operates at a fixed-frequency of 2 MHz (typical). Internal synchronous rectification provides high efficiency during the PWM mode operation. In shutdown mode, the device turns off and reduces battery consumption to 0.01 µA (typical).
The LM3674 is available in a 5-pin SOT-23 package. A high switching frequency of 2 MHz (typical) allows use of only three tiny external surface-mount components, an inductor and two ceramic capacitors.
PART NUMBER | PACKAGE | BODY SIZE (NOM) |
---|---|---|
LM3674 | SOT-23 (5) | 2.90 mm × 1.60 mm |
Changes from F Revision (May 2013) to G Revision
Changes from E Revision (April 2013) to F Revision
PIN | TYPE | DESCRIPTION | |
---|---|---|---|
NAME | NUMBER | ||
EN | 3 | Digital | Enable input. The device is in shutdown mode when voltage to this pin is < 0.4 V and enable when > 1 V. Do not leave this pin floating. |
FB | 4 | Analog | Feedback analog input. Connect to the output filter capacitor, COUT, for fixed voltage versions. For adjustable version, external resistor dividers are required (R1 and R2). The internal resistor dividers are disabled for the adjustable version. |
GND | 2 | Ground | Ground pin |
SW | 5 | Analog | Switching node connection to the internal PFET switch and NFET synchronous rectifier. |
VIN | 1 | Power | Power supply input. Connect to the input filter capacitor, CIN. |