1 Introduction

In light-load conditions, the TPS564242 operates in Eco mode to enable higher efficiency by varying its switching frequency, and the TPS564247 operates in FCCM to maintain constant switching frequency. The main difference is at light loading, but the other behaviors are similar. This user's guide mainly introduces the TPS564242 and includes some features about the TPS564247 that are different from the TPS564242.

The TPS56424x is a single, adaptive on-time, D-CAP3™ mode, synchronous buck converter requiring a very low external component count. The D-CAP3 control circuit is optimized for low-ESR output capacitors such as POSCAP, SP-CAP, or ceramic types and features fast transient response with no external compensation. The switching frequency is internally set at a nominal 1200 kHz. The high-side and low-side switching MOSFETs are incorporated inside the TPS56424x package along with the gate-drive circuitry. The low drain-to-source on resistance of the MOSFETs and fast switching slew rate allow the TPS56424x to achieve high efficiencies and helps keep the junction temperature low at high output currents. The TPS56424x DC/DC synchronous converter is designed to provide up to a 4-A output from an input voltage source of 3 V to 16 V. The output voltage range is from 0.6 V to 7 V. Rated input voltage and output current ranges for the evaluation module are given in Table 1-1.

The TPS564242EVM evaluation module (EVM) is a single, synchronous buck converter providing 1.05 V at 4 A from 3-V to 16-V input. This user’s guide describes the TPS564242EVM performance.