SLVSE84D December 2017 – July 2021 TLV767
For improved output accuracy, use Equation 12 and IFB = 50 nA as listed in the Electrical Characteristics table to calculate the upper limit for series feedback resistance (R1 + R2 ≤ 660 kΩ).
The control-loop error amplifier drives the FB pin to the same voltage as the internal reference (VFB = 0.8 V, as listed in the Electrical Characteristics table). Use Equation 11 to determine the ratio of R1 / R2 = 3.125. Use this ratio and solve Equation 12 for R2. Now calculate the upper limit for R2 ≤ 160 kΩ. Select a standard value resistor for R2 = 160 kΩ.
Reference Equation 11 and solve for R1: