A good PCB layout for the LF33ABDT-TR involves keeping the input and output capacitors close to the device, using a solid ground plane, and minimizing the length of the input and output traces. A 4-layer PCB with a dedicated power plane and a solid ground plane is recommended.
To ensure stability, it's essential to follow the recommended PCB layout, use a sufficient output capacitor (at least 10uF), and add a 1-2nF capacitor between the output and the feedback pin. Additionally, ensure that the input voltage is within the recommended range, and the output current is within the specified limits.
The maximum allowed input voltage ripple for the LF33ABDT-TR is 10% of the input voltage. Exceeding this limit may affect the device's performance and stability.
The LF33ABDT-TR is rated for operation up to 125°C. However, the device's performance and reliability may degrade at high temperatures. It's essential to ensure proper heat dissipation and consider the device's thermal characteristics when designing for high-temperature applications.
The output voltage tolerance can be calculated by considering the device's output voltage accuracy (±2% for the LF33ABDT-TR) and the tolerance of the external resistors used to set the output voltage. A total tolerance of ±4% is a reasonable estimate.
LF33ABDT-TR datasheet
by STMicroelectronics
