A precision 0.8-V reference voltage (VREF) is used to maintain a tightly regulated output voltage over the entire operating temperature range. The output voltage is set by a resistor divider from VOUT to the FB pin. It is recommended to use 1% tolerance resistors with a low temperature coefficient for the FB divider. Select the bottom-side resistor, RFBB, for the desired divider current and use Equation 1 to calculate the top-side resistor, RFBT. The recommended range for RFBT is 10 kΩ to 100 kΩ. A lower RFBT value can be used if pre-loading is desired to reduce the VOUT offset in PFM operation. Lower RFBT values reduce efficiency at very light load. Less static current goes through a larger RFBT value and can be more desirable when light-load efficiency is critical. However, RFBT values larger than 1 MΩ are not recommended because they make the feedback path more susceptible to noise. Larger RFBT values require a more carefully designed feedback path trace from the feedback resistors to the feedback pin of the device. The tolerance and temperature variation of the resistor divider network affect the output voltage regulation.