1 Introduction

In light-load conditions, the TPSM863252 operates in Eco-mode to enable higher efficiency by varying the switching frequency, and the TPSM863253/7 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 TPSM863252 and includes some TPSM863253/7 features that are different from the TPSM863252.

The TPSM86325x is a single, adaptive on-time, D-CAP3™ control mode, synchronous buck converter module that requires 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 1.2 MHz. The high-side and low-side switching MOSFETs are incorporated inside the TPSM86325x package along with the gate-drive circuitry. The low drain-to-source on resistance of the MOSFETs and fast switching slew rate allow the TPSM86325x to achieve high efficiency and help keep the junction temperature low at high output currents. Power sequencing is possible by correctly configuring the enable and power-good indicator. The TPSM86325x DC/DC synchronous converter module is designed to support up to a 3-A continuous current from an input voltage source of 3 V to 17 V. 0.6 V to 10 V output voltage range for TPSM863252, fixed 3.3V output voltage for TPSM863253 and 0.6 V to 5.5 V output voltage range for TPSM863257. Rated input voltage and output current ranges for the evaluation module are given in Table 1-1.

The TPSM863252EVM evaluation module (EVM) is a single, synchronous buck converter module providing 1.05 V at 3 A from 3-V to 17-V input. This user’s guide describes the TPSM863252EVM performance.