LM78S40CN/NOPB datasheet by Texas Instruments

LM78S40CN/NOPB Frequently Asked Questions (FAQs)

• What is the maximum input voltage that the LM78S40CN/NOPB can handle?
  The maximum input voltage is 35V, but it's recommended to keep it below 25V for reliable operation.
• Can I use the LM78S40CN/NOPB in a high-temperature environment?
  The LM78S40CN/NOPB is rated for operation up to 125°C, but thermal derating is required above 85°C. Ensure proper heat sinking and thermal management to prevent overheating.
• How do I ensure the output voltage is stable and regulated?
  Use a minimum of 10uF capacitor on the input and output pins, and ensure the input voltage is at least 2V above the desired output voltage. Also, keep the regulator away from noise sources and ensure good PCB layout practices.
• Can I use the LM78S40CN/NOPB in a switching power supply application?
  No, the LM78S40CN/NOPB is a linear regulator, not suitable for switching power supply applications. It's designed for low-dropout, low-noise, and high-reliability applications.
• What is the minimum load current required for the LM78S40CN/NOPB to regulate properly?
  The LM78S40CN/NOPB can regulate with no minimum load current, but it's recommended to have at least 5mA load current for optimal performance.