A good PCB layout for optimal thermal performance involves placing the device near a thermal pad or a heat sink, and ensuring good copper pour coverage around the device. Additionally, using a 2-3 layer PCB with a solid ground plane can help to reduce thermal resistance.
To ensure reliable start-up, it is recommended to add a soft-start circuit to the input voltage, and to use a capacitor with a low equivalent series resistance (ESR) at the input. Additionally, adding a noise filter, such as an LC filter, can help to reduce the impact of noise on the power supply.
The maximum allowed voltage transient on the input pin is 20% above the maximum recommended operating voltage, but not exceeding 24V. However, it is recommended to limit the voltage transient to 10% above the maximum recommended operating voltage to ensure reliable operation.
The output voltage ripple can be calculated using the formula: ΔVout = (Iout * Rl) / (f * Cout), where Iout is the output current, Rl is the load resistance, f is the switching frequency, and Cout is the output capacitance.
A low-ESR ceramic capacitor with a value of 10-22uF is recommended for optimal performance. The capacitor should be placed as close to the device as possible to minimize parasitic inductance.
LMZ14203HTZE/NOPB datasheet
by Texas Instruments
