This document describes a multi-rail DC/DC converter that can generate multiple outputs from inputs as low as 0.7V. By connecting the input sources of the LTC3100 to the boost converter and buck converter, a regulated 3.3V output can be generated from single-cell or dual-cell input voltage. When USB or wall adapter power is available, the buck converter is automatically enabled and generates a 3.3V output that is set 3.8% higher than that of the boost converter. This puts the boost converter in sleep mode, reducing the load on the batteries. This allows for seamless transition from battery power to USB power.
The LTC3100 is a high efficiency, 1.5MHz multichannel DC/DC converter available in a compact 3mm x 3mm x 0.75mm QFN package. It features a synchronous step-up (boost) DC/DC converter, a synchronous step-down (buck) DC/DC converter, and a 100mA low dropout linear regulator (LDO). The boost and buck converters can operate independently from different sources or be cascaded to create a buck-boost converter.
| Operating Frequency | 1.5MHz |
|---|---|
| Package Dimensions | 3mm x 3mm x 0.75mm QFN |
| Boost Efficiency | Up to 95% |
| Buck Efficiency | Up to 94% |
| Minimum Input Voltage (Boost) | 700mV |
| LDO Output Current | 100mA |
The boost converter can start with input voltages as low as 700mV.
Yes, the boost and buck converters can operate independently from different sources or from the same source.
The device operates at a frequency of 1.5MHz.