ZHCSE52B September 2015 – May 2019 TPS57140-EP
PRODUCTION DATA.
For the example design, the selected resistance for R2 is 10 kΩ. Using Equation 1, the calculated value of R1 is 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 to maintain the output voltage accuracy. This requirement makes the maximum value of R2 equal to 800 kΩ. Choosing higher resistor values decreases quiescent current and improves efficiency at low output currents, but may introduce noise-immunity problems.