Texas Instruments provides a recommended PCB layout in the datasheet, but it's also recommended to follow general high-frequency PCB design guidelines, such as using a solid ground plane, minimizing trace lengths, and using bypass capacitors to reduce noise and ringing.
The LM8342SD has a thermal pad on the bottom of the package, which should be connected to a thermal plane on the PCB. Ensure good thermal conductivity by using a thermal interface material (TIM) and a heat sink if necessary. Also, follow the recommended operating temperature range and power dissipation guidelines.
While the datasheet specifies a maximum input voltage of 42V, it's recommended to derate the input voltage to ensure reliable operation. A general rule of thumb is to limit the input voltage to 80% of the maximum rating, which would be around 33.6V for the LM8342SD.
Start by verifying the PCB layout and component values match the recommended design. Check for proper power supply decoupling, and ensure the input and output capacitors are of sufficient value and type. Use an oscilloscope to measure the output voltage and current, and look for signs of oscillation or instability. Consult the datasheet and application notes for troubleshooting guides and tips.
The LM8342SD is a commercial-grade device, but it can be used in high-reliability or automotive applications with proper design and testing. Ensure the device is operated within its recommended specifications, and follow industry standards for reliability and testing, such as AEC-Q100 or MIL-STD-883.
LM8342SD/NOPB datasheet
by Texas Instruments
