ZHCSLU2C December 2021 – August 2024 LM63440-Q1 , LM63460-Q1
PRODUCTION DATA
The LM63440-Q1 or LM63460-Q1 uses a feedback divider network to set the output voltage. The divider network comprises top and bottom feedback resistors designated as RFBT and RFBB, respectively. The resistances of the feedback divider are a compromise between excessive noise pickup and quiescent current consumption. Lower resistance values reduce noise sensitivity but also impact light-load efficiency. The recommended value for RFBT is 100kΩ with a maximum value of 1MΩ. If 1MΩ is selected for RFBT, then use a feedforward capacitor in parallel to provide adequate loop phase margin. Use Equation 1 to find RFBB for a given value of RFBT. Choosing RFBT and RFBB values of 102kΩ and 25.5kΩ, respectively, sets the output voltage at exactly 5V.