6.5 Adjustable Regulator Design

The adjustable MIC38300 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 100 kΩ because of the very high input impedance and low bias current of the sense amplifier. For large value resistors (>50 kΩ) R1 should be bypassed by a small capacitor (C_FF = 0.1 μF bypass capacitor) to avoid instability due to phase lag at the ADJ/SNS input.

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

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