Is it possible to use LDO regulators at low supply voltage? What is the minimum voltage required for their proper operation?

LDO regulators provide a regulated output voltage (V_OUT) when the input voltage (V_IN) is higher than the specified output voltage by at least the minimum dropout voltage (V_DO). Therefore, an LDO regulator with a typical V_OUT of 1.1 V and a typical V_DO of 120 mA can regulate V_OUT to 1.1 V when V_IN = 1.22 V.

V_DO is dependent on output current. As output current increases, V_DO increases.

To ensure that LDO regulators operate properly, care should be exercised as to variations in V_IN, temperature characteristics of V_DO, and output current characteristics.

For operation at low supply voltage, select LDO regulators with low output voltage (V_OUT) and low dropout voltage (V_DO).

Click the following links to view our lineup of LDO regulators with low dropout voltage.

Please also refer to the following documents for related explanations.

Application note

• Power Effiiency Optimization and Application Circuits Using Dual-power-supply LDO Regulators
• Basics of Low-Dropout(LDO) Regulators ICs
• LDO Regulators Glossary

FAQ

• Which characteristics in a datasheet should I refer to in order to determine whether a given LDO maintains a regulated output voltage even when input voltage varies?
• What voltage is required at the CONTROL terminal to enable an LDO?
• Why is the output of an LDO disabled when its input voltage decreases?
• Is it OK to reverse-bias an LDO, causing its output voltage to become higher than the input voltage?

To product list of LDO ICs :

• Low dropout noise voltage Products

Main web page about LDO ICs:

• Low-Dropout Regulators(LDO Regulators)

Otherinformation

• e-learning Power Management IC
• Noise reduction due to high ripple rejection ratio