Texas Instruments provides a recommended PCB layout in the datasheet, but it's also important to follow general best practices for switching regulator layouts, such as keeping the input and output capacitors close to the IC, using a solid ground plane, and minimizing trace lengths and widths.
The datasheet provides a list of recommended inductors, but you should also consider factors such as inductor saturation current, DC resistance, and core material. You can use online inductor selection tools or consult with an applications engineer to find the best inductor for your specific application.
The datasheet specifies an operating junction temperature range of -40°C to 150°C, but the maximum ambient temperature range depends on the specific application and the thermal design of the system. You should ensure that the IC's junction temperature remains within the specified range to ensure reliable operation.
The LM4674SQ is a commercial-grade device, but Texas Instruments offers other versions of the device that are qualified for high-reliability or automotive applications, such as the LM4674SQ-Q1 or LM4674SQ-AQ. You should consult with an applications engineer to determine the best device for your specific application.
Texas Instruments provides a troubleshooting guide in the datasheet, but you can also use tools such as an oscilloscope or a frequency analyzer to identify the root cause of the issue. You should also ensure that the device is properly soldered, and that the PCB layout and component selection are correct.
LM4674SQ/NOPB datasheet
by Texas Instruments
