A good PCB layout for optimal thermal performance would be to have a solid ground plane on the bottom layer, and to use thermal vias to connect the exposed pad to the ground plane. This helps to dissipate heat efficiently.
To ensure stability and prevent oscillations, it's essential to follow the recommended component values and PCB layout guidelines. Additionally, make sure to use a sufficient output capacitor with a low ESR value, and consider adding a small ceramic capacitor in parallel with the output capacitor to filter out high-frequency noise.
Although the datasheet specifies a maximum input voltage of 15V, it's recommended to limit the input voltage to 12V to ensure reliable operation and prevent overheating.
While the AP2111SG-13 is rated for operation up to 125°C, it's essential to consider the thermal derating curve and ensure that the device does not exceed the maximum junction temperature. In high-temperature environments, consider using a heat sink or a thermal interface material to improve heat dissipation.
To calculate the output voltage ripple and noise, consider the output capacitor value, ESR, and ESL. A good starting point is to use the equations provided in the datasheet or to use a simulation tool like SPICE to model the circuit and estimate the output voltage ripple and noise.
AP2111SG-13 datasheet
by Diodes Incorporated
