TPS54A20 Step-Down Converter

Texas Instruments' TPS54A20 is a two-phase, synchronous series capacitor buck converter designed for small-size, low-voltage applications from a 12 V input rail. This topology uniquely merges a switched capacitor circuit with a two-phase buck converter. Advantages include automatic current balancing between the inductors, lower switching losses (which enable high-frequency (HF) operation), and voltage step-down through the series capacitor. Small, low-profile inductors used with the TPS54A20 significantly reduce total solution area and height. An adaptive, on-time control architecture provides fast transient response and accurate voltage regulation at up to 10 MHz operating frequency. Fixed frequency operation during steady state is maintained through the use of a phase lock loop (PLL) to lock switching signals to a reference oscillator.