Is the power-on sequence of the input voltage (VIN) and the control voltage (VCT) of an LDO significant?

Power up VIN and VCT in the following sequence. Power down VIN and VCT in the order opposite to the power-up sequence.

Single-power-supply LDOs

In the case of single-power-supply LDOs, the internal control circuitry is supplied from VIN. For an LDO to work properly, VIN must be fully powered up to a nominal voltage level prior to the application of VCT.

Dual-power-supply LDOs

In the case of dual-power-supply LDOs, the internal control circuitry is supplied from the bias voltage terminal (either VBIAS or VBAT). Therefore, VBIAS or VBAT must be fully powered up to a nominal voltage level, followed by VIN and then VCT.

Figure 1 Power sequence of single-power-supply LDOs
Figure 1 Power sequence of single-power-supply LDOs
Figure 2 Power sequence of dual-power-supply LDOs
Figure 2 Power sequence of dual-power-supply LDOs

To perform a parametric search of single-power-supply LDOs, click:

To perform a parametric search of dual-power-supply LDOs, click:

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

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