LT138AK datasheet by Linear Technology

LT138AK Frequently Asked Questions (FAQs)

• What is the maximum input voltage that can be applied to the LT138AK?
  The maximum input voltage that can be applied to the LT138AK is 80V, but it's recommended to keep it below 70V for reliable operation.
• How do I ensure the LT138AK is stable and doesn't oscillate?
  To ensure stability, make sure to follow the recommended layout and component selection guidelines, including using a low-ESR output capacitor and a minimum output load of 1mA. Also, avoid using long input traces and keep the input capacitor close to the IC.
• What is the minimum input voltage required for the LT138AK to operate?
  The minimum input voltage required for the LT138AK to operate is 3.5V, but it's recommended to keep it above 4V for reliable startup and operation.
• Can I use the LT138AK in a high-temperature environment?
  The LT138AK is rated for operation up to 125°C, but its performance and reliability may degrade at high temperatures. It's recommended to derate the output current and voltage according to the temperature derating curve in the datasheet.
• How do I calculate the output voltage ripple of the LT138AK?
  The output voltage ripple of the LT138AK can be calculated using the formula: ΔVout = (Iout * ESL) / (Cout * fsw), where Iout is the output current, ESL is the equivalent series inductance of the output capacitor, Cout is the output capacitance, and fsw is the switching frequency.