描述 Description

The LM3678 step-down DC-DC converter is optimized for powering low-voltage circuits from a single Li-Ion cell battery and input voltage rails from 2.5 V to 5.5 V. It provides up to 1.5-A load current, over the entire input voltage range. LM3678 offers a 0.8V or 1.2V option. One of the pair of voltages is set through the VSELECT pin. LM3678 operates in PWM mode with a fixed frequency of 3.3 MHz. Internal synchronous rectification provides high efficiency during PWM mode operation. In shutdown mode, the device turns off and reduces battery consumption to 0.01?μA (typical).The LM3678 is available in a 3mm x 3mm DSC-10 package. A high switching frequency of 3.3?MHz (typical) allows use of tiny surface-mount components. Only three external surface-mount components, an inductor and two ceramic capacitors, are required (solution size less than 33 mm2). For voltages other than the voltage shown, contact TI or your distributor.

特性 Features

? VOUT = 0.8 V or 1.2 V
? VIN = 2.5 V to 5.5 V
? 1.5-A Maximum Load Capability
? 3.3-MHz (Typical) PWM Fixed Switching Frequency Allows Use of 1-μH Inductor
? ±3% DC Output Voltage Precision
? 0.01-μA (Typical) Shutdown Current
? Internal Synchronous Rectification for High Efficiency
? Internal Soft Start
? Current Overload and Thermal Shutdown Protection