6.5 Adjustable Regulator Design

The adjustable MIC38150 output voltage can be programmed from 1V to 5.0V using a resistor divider from output to the FB pin. Resistors can be quite large, up to 100kΩ because of the very high input impedance and low bias current of the sense amplifier. For large value resistors (>50kΩ), R1 should be bypassed by a small capacitor (CFF = 0.1μF bypass capacitor) to avoid instability due to phase lag at the ADJ/SNS input.

The output resistor divider values are calculated using the equation below:

$V_{OUT}=1V\times (\frac{R1}{R2}+1)$