Texas Instruments provides a recommended PCB layout in the application note SLVAU65, which includes guidelines for thermal vias, copper pours, and component placement to minimize thermal resistance and ensure reliable operation.
To ensure reliable start-up and shutdown, it is recommended to follow the soft-start and shutdown procedures outlined in the datasheet, and to use a suitable input capacitor to filter out noise and ripple. Additionally, the EN pin should be driven with a clean, glitch-free signal.
The maximum allowable voltage on the VIN pin during startup is 42V, as specified in the datasheet. Exceeding this voltage can cause damage to the device. It is recommended to use a suitable input voltage regulator or transient voltage suppressor to protect the device from voltage spikes and surges.
The output voltage ripple and noise can be calculated using the equations provided in the datasheet, which take into account the output capacitor value, ESR, and switching frequency. Additionally, the application note SLVAU65 provides guidance on how to measure and minimize output voltage ripple and noise.
The recommended input capacitor type is a low-ESR ceramic or film capacitor, with a value of 10uF to 22uF. The capacitor should be rated for the maximum input voltage and should be placed as close as possible to the VIN pin to minimize noise and ripple.
LM3450AMT/NOPB datasheet
by Texas Instruments
