A recommended PCB layout for optimal thermal performance would be to use a 2-layer or 4-layer board with a solid ground plane on the bottom layer, and to place thermal vias under the IC to dissipate heat effectively.
To ensure stable output voltage regulation, it's essential to follow the recommended component values and PCB layout guidelines, and to decouple the input and output pins with suitable capacitors. Additionally, the output voltage should be set using a resistive divider network with a minimum of 1kΩ impedance.
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 to prevent damage to the internal components.
The AP1121ASL-13 is rated for operation up to 125°C, but it's essential to consider the thermal derating curve and to ensure that the junction temperature (Tj) does not exceed 150°C. Proper heat sinking and thermal management are crucial in high-temperature environments.
To protect the AP1121ASL-13 from input voltage surges or spikes, it's recommended to add a transient voltage suppressor (TVS) diode or a voltage clamp circuit at the input pin. This will help to limit the voltage stress on the internal components and prevent damage.
AP1121ASL-13 datasheet
by Diodes Incorporated
