# Power delay for secondary device

#### puneethskumar

Joined Nov 18, 2019
11
Dear Team,
There is a pull up resistor at one end i am giving a voltage of +3.3v but while measuring on the other end initial i am getting 1.6v & later after some time i am getting 2.5v that time my secondary device is getting power.

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#### AlbertHall

Joined Jun 4, 2014
11,212
If you want more than guesses then more information is required. A schematic would be great help.

#### puneethskumar

Joined Nov 18, 2019
11
VCC=3V,

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#### AlbertHall

Joined Jun 4, 2014
11,212
The resistor and capacitor have a time constant of 100ns. For the voltage to rise close the final value will take about ten times that or 1ms.
Are you seeing a delay greater that?

#### AnalogKid

Joined Aug 1, 2013
9,157
The final output voltage depends on the impedance or current draw of whatever the output is connected to. Please describe the system that this circuit is in, and what the "Output" goes to.

ak

#### TeeKay6

Joined Apr 20, 2019
572
The resistor and capacitor have a time constant of 100ns. For the voltage to rise close the final value will take about ten times that or 1ms.
Are you seeing a delay greater that?
100ns? Are you sure of your math?

#### AlbertHall

Joined Jun 4, 2014
11,212
100ns? Are you sure of your math?
I was only out by a factor of 1000. That's closer than many of our politicians are (UK).
It should be 100us so final settling in 1ms.

#### TeeKay6

Joined Apr 20, 2019
572
I was only out by a factor of 1000. That's closer than many of our politicians are (UK).
It should be 100us so final settling in 1ms.
You had the right result so let's just accept that you accidentally typed an "n" instead of "u". I don't think there is much difference among politicians of any country: tell them what they want to hear, then do what you always intended to do.

#### puneethskumar

Joined Nov 18, 2019
11
The resistor and capacitor have a time constant of 100ns. For the voltage to rise close the final value will take about ten times that or 1ms.
Are you seeing a delay greater that?

true.. But in my circuit it is taking more than 1min

#### puneethskumar

Joined Nov 18, 2019
11
The final output voltage depends on the impedance or current draw of whatever the output is connected to. Please describe the system that this circuit is in, and what the "Output" goes to.

ak

There is a IC which generates internal 3.3V I am using that voltage , there is a reset pin in that IC(It should be high) , so typically when voltage is low the power is not going.