Texas Instruments provides a recommended PCB layout in the datasheet, but it's essential to follow good layout practices, such as keeping the input and output traces short, using a solid ground plane, and minimizing noise coupling. Additionally, consider using a 4-layer PCB with a dedicated power plane and a separate ground plane.
To ensure stable output voltage regulation, make sure to decouple the input and output pins with suitable capacitors, and use a stable input voltage source. Also, ensure that the output capacitor is properly sized and placed close to the output pin. Finally, consider adding a soft-start circuit to prevent inrush currents during startup.
Although the datasheet specifies a maximum input voltage of 18V, it's recommended to limit the input voltage to 15V to ensure reliable operation and prevent damage to the device. Exceeding the maximum input voltage can lead to reduced performance, increased power consumption, or even device failure.
To calculate the output voltage ripple and noise, consider the output capacitor value, equivalent series resistance (ESR), and the switching frequency. You can use the following formula: ΔVout = (Iout * ESR) / (Cout * fsw), where Iout is the output current, ESR is the output capacitor's ESR, Cout is the output capacitor value, and fsw is the switching frequency.
The thermal derating curve for the TRS3318ECDBR is not explicitly provided in the datasheet. However, you can use the following general guideline: for every 10°C increase above 25°C, the maximum output current should be derated by 10%. This ensures reliable operation and prevents overheating.
TRS3318ECDBR datasheet
by Texas Instruments
