Hey guys,

I need to make a Power ON Delay Circuit with variable delay from 1sec to 10sec using 555 and a pot(variable resistor).
That is when power is given to the circuit it must not produce an output until the delay time(say 1sec to 10sec).
Providing a schematic diagram with time delay equation will be sufficient.
Thank you.........
Its Very Urgent.........

 

http://home.cogeco.ca/~rpaisley4/LM555.html#29

Ken

 

 

Hey Bill,what's the value for the other Resistors and capacitors...?
In the T=1.1RC equation,R in ohms and C in farads or microfards.......?
pls reply.
i'm looking forward to your circuit......

 

What are the values of R1, C1, C2, R2?

 

He wants a delayed pulse, you need to change the transistor for a Pnp, that circuit will operate immediately...

 

I want the relay switch to operate another circuit which will switch on after a delay, would that still be the same case?

 

Hey guys,

I need to make a Power ON Delay Circuit with variable delay from 1sec to 10sec using 555 and a pot(variable resistor).
That is when power is given to the circuit it must not produce an output until the delay time(say 1sec to 10sec).
Providing a schematic diagram with time delay equation will be sufficient.
Thank you.........
Its Very Urgent.........

 

This is a standard monostablewhose trigger is the power on itself.The formula t.7Rt and=Ct applies. a 1Korm for the base resistor will likely suffice.R1=10K and C1=1uf

Wendy's Index

I have had stroke
This jusr means I am not as sharp as usual.

555 Monostable

 

I want the relay switch to operate another circuit which will switch on after a delay, would that still be the same case?

Yes, The relay is to handle power

 

This is a standard monostablewhose trigger is the power on itself.The formula t.7Rt and=Ct applies. a 1Korm for the base resistor will likely suffice.R1=10K and C1=1uf

Wendy's Index

I have had stroke
This jusr means I am not as sharp as usual.

555 Monostable

That's just a semi-standard 555 one-shot and won't work as a POWER-ON delay:

 

But this is... *Wow this was started in the year2009

R1=10K, R2 =1K
Q1= 2N22222
C1=0.1uf

 

But this is... *Wow this was started in the year2009

R1=10K, R2 =1K
Q1= 2N22222
C1=0.1uf

Regardless, pin 2 will be low when Vcc goes high, (t0) which will unconditionally drive pin 3 high immediately instead of delaying its rise for t0 + 1.1RtCt.