TPS54678 is the recommended alternative device to TPS54673. Please refer to the TPS54678EVM for new device evaluation.
The TPS54673EVM kit allows the designer to easily evaluate the 6 A TPS54673 synchronous buck DC/DC Converter with disabled sinking during startup (DSDS). The module provides 4 series diodes to allow the user to pre-charge the output from the EVM input voltage or an external source. The input voltage range is 3-6 V and the output voltage is adjustable down to 0.9 V (module preset to 2.5 V). Other voltages are possible by changing the resistor divider.
Please see the TPS54673EVM User's Guide (SLVU079) document for more information.