SBVS411A August 2020 – October 2020 TPS784
PRODUCTION DATA
The device requires external feedback divider resistors to set the output voltage. Figure 8-1 shows how the output voltage can be configured from 1.2 V to 5.5 V by using a resistor divider network.
Equation 2 calculates how the R1 and R2 resistors are used to set the output voltage:
To disregard the effect of the FB pin current error term in Equation 2 and to achieve best accuracy, choose R2 to be smaller than 550 kΩ so that the current flowing through R1 and R2 is at least 100 times larger than the IFB current listed in the Electrical Characteristics table. Lowering the value of R2 increases the immunity against noise injection. Increasing the value of R2 reduces the quiescent current for achieving higher efficiency at low load currents. Equation 3 calculates the setting that provides the maximum feedback divider series resistance.