Compact High Efficiency Synchronous Buck-Boost Converter for High-Power Density Portable Applications

Published  August 10, 2018   0
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Compact High Efficiency Synchronous Buck-Boost Converter for High-Power Density Portable Applications

Diodes Incorporated released AP72200, a high-current synchronous buck/boost DC-DC converter with integrated high-side and low-side H-Bridge MOSFETs, which delivers up to 97% efficiency with 1% voltage regulation accuracy, low quiescent current, and very low output ripple.

By using the Diodes Incorporated’s proprietary buck/boost current-mode control technology, the AP72200 provides an excellent voltage regulation and a continuous output current of up to 2A. The design allows for seamless transition between buck and boost operation while the wide 2.3V to 5.5V input voltage range provides flexibility of supply and produces between 2.6V to 5.14V output voltage.

AP72200 device’s high level of integration with low quiescent current and wide input voltage range, make it well-suited for a wide range of portable applications including smart phones, tablets, and other battery-operated consumer devices.

Many of the features of the AP72200 are user-configurable through an industry-standard I2C interface, which can operate in standard mode, fast mode, fast-mode plus, and high-speed mode. This includes programmable-output voltage ramp-up and ramp-down slew-rates, output-active discharge, over-voltage protection threshold, and over-current threshold. The AP72200 can also be configured to operate in PWM or PFM mode, as well as in ultrasonic mode, which reduces the switching frequency to avoid the generation of sub-harmonic frequencies in the region of 20kHz that can cause interference in the audible frequency range. In addition, the buck/boost output can also be disabled using the I2C interface, allowing a master device to control the operation of the regulator across a standard I2C bus. The output voltage can be set to between 2.60V and 5.14V in 0.02V increments by programming the device over I2C.

The integrated H-Bridge MOSFETs feature extremely low RDS(ON) of 25mΩ and a shutdown current of less than 1µA. Quiescent current is as low as 20µA when operating in non-switching mode and a typical of 29µA in PFM mode. Moreover, the switching frequency in continuous switching mode is typically 2.5MHz, dropping to 27kHz in ultrasonic mode.