The output voltage of an adjustable-output LDO is programmable via two resistors. The capacitor connected to the upper resistor (R1) is called a feedback capacitor (CFB). It is added to prevent oscillation, improve load transient response, and increase the ripple rejection ratio (R.R.) (also known as the power supply rejection ratio or PSRR for short). CFB and R1 introduce a zero and thus provide lead phase compensation, increasing an oscillation margin and improving load transient response.