The LDO regulates its output voltage using negative feedback. The output voltage oscillates when the phase of the signal to detect changes in the output voltage (VOUT) lags by 180°, turning negative feedback into positive feedback. The LDO incorporates an error amplifier, a drive circuit for an output transistor, and the output transistor. The feedback loop has an inherent delay due to the capacitance and resistance of these circuits. If the loop has a gain, negative feedback turns into positive feedback when the phase delay due to this inherent delay reaches 180°, causing the difference between the output and reference voltages to be amplified.