This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPS7A24: Why TPS7A24 has a wait time until Vout bringing up ?

Part Number: TPS7A24
Other Parts Discussed in Thread: TPS7A26

Hi Sir,

Now I design 3.6V power rail by using TPS7A2401 and check the start up behaviour.

In case of normal LDO, Vout is up as same as Vin simultaneously. However TPS7A2401 has a wait time as below. (It's  about 1ms)

Could you tell me why TPS7A24 has a wait time until Vout bring up? and How to calculate this wait time?

It looks like something trigger to bring up Vout.

Here is my condition.

Vin : 6V, Vout : 3.6V

Cin : 1uF, Cout : 10uF, Cff : 10nF

Regards,

  • Hello, 

    Thank you for sharing this information with us. 

    When you mention normal LDO, do you happen to know the part number or that other LDO? Also, is EN=Vin? 

    Different devices have different internal circuitry, and depending on the design and features, this could vary. This delay time is quite typical for this device: 

    These are taken from TPS7A26 DS, which is very similar to TPS7A24 and will exhibit some of the same performance like startup.

    And the scope shot below is taken from other bench data showing that it could have a 1ms from when Vin and EN are brought up. 

    Do you know what is the time requirement? Perhaps we can see if another LDO is a better fit for your application. 

    Best, 

    Edgar Acosta