1A, Low Noise Synchronous Buck-Boost DC/DC Converter

摘要

LINEAR TECHNOLOGY announces the LTC3536, a synchronous buck-boost converter that delivers up to 1A of output current from a Li-Ion/ Polymer source or 300mA from dual cell alkaline/NiCd/NiMH sources. Its 1.8V to 5.5V input and output voltage range achieves a ±1% accurate output with inputs above, below or equal to the regulated output. The latest generation single inductor buck-boost pulse width modulation (PWM) topology incorporated in the LTC3536 provides a continuous transition through all of the operating modes, making it ideal for noise-sensitive applications that must maintain a constant output voltage even as the battery voltage declines below the output. In many cases, this can increase battery run time 25% versus a buck regulator. The LTC3536's switching frequency is user programmable from 300kHz to 2MHz and can be synchronized to a system clock, optimizing the trade-off between efficiency and external component size. The combination of 1% output voltage accuracy, low noise, tiny externals and a 3mm × 3mm DFN package provides a very small solution footprint, typically required in many handheld RF and precision measurement applications.