What is the purpose of the capacitor connected to one of the external resistors for an adjustable-output LDO?

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 (C_FB). 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). C_FB and R₁ introduce a zero and thus provide lead phase compensation, increasing an oscillation margin and improving load transient response.

To view the lineup of adjustable-output LDOs to which a feedback capacitor (CFB) can be connected, click:

• Lineup of adjustable-output LDOs to which a feedback capacitor (CFB) can be connected

For other LDO regulators, visit the main web page of LDO regulators at:

• LDO Regulators