ZHCSF14D March 2010 – October 2018 TPS54260
PRODUCTION DATA.
The voltage divider of R5 and R6 is used to set the output voltage. For the example design, 10.0 kΩ was selected for R6. Using Equation 1, R5 is calculated as 31.25 kΩ. The nearest standard 1% resistor is 31.6 kΩ. Due to current leakage of the VSENSE pin, the current flowing through the feedback network should be greater than 1 μA in order to maintain the output voltage accuracy. This requirement makes the maximum value of R2 equal to 800 kΩ. Choosing higher resistor values will decrease quiescent current and improve efficiency at low output currents but may introduce noise immunity problems.