4V-to-18V input, 35A, stackable PMBus synchronous step-down converter

The TPS546C25 device is a highly-integrated buck converter with D-CAP4 control topology for fast transient response. All programmable parameters can be configured by the PMBus interface and stored in NVM as the new default values to minimize the external component count. Pin-strap options allow for configuration as primary or secondary, stack position and stack number, DCM (single phase only) or FCCM, overcurrent limit, fault response, internal or external feedback resistor, output voltage selection or range, switching frequency, and compensation.

The PMBus interface with 1MHz clock support gives a convenient, standardized, digital interface for configuration as well as telemetry of key parameters including output voltage, output current, and internal die temperature. Response to fault conditions can be set to restart, latch off, or ignore, depending on system requirements. Two, three, and four TPS546C25 devices can be interconnected to provide up to 140A on a single output.

The TPS546C25 has an option to overdrive the internal 4.5V LDO with an external 5V supply through the to improve efficiency, reduce power dissipation, and enable start-up with a lower input voltage.

The TPS546C25 is a lead-free device and is RoHS compliant without exemption.