0.3V Detection Circuit

[Suraj143]

I have the below wave form. Can somebody tell me a very basic circuit to detect the red colour area.High/ low will be fine.

Thanks

 

[ericgibbs]

I have the below wave form. Can somebody tell me a very basic circuit to detect the red colour area.High/ low will be fine.

Thanks

hi,
A LM393 comparator could be set to detect this level.

 

[Suraj143]

Thanks ericgibbs.

Is there any simple transistor solution?

Because I'm getting the signals from 4 channels.So I need to make 4 IC circuits.It must be a very small circuit.

 

[reader1]

That's easy, you can choice LM339, which is just 4 cell for use.

 

[Grossel]

Here's a easy way doing this. However you need negative voltage supply AND you need to calculate resistors in voltage divider. AND you need an and gate (i omitted drawing a bjt-and gate).

 

[Nigel Goodwin]

From the look of that waveform he needs a sync-seperator, there are some really good IC ones, or a simple single transistor will do the job.

 

[blueroomelectronics]

The LM1881 is a classic sync separator.

 

[Grossel]

From the look of that waveform he needs a sync-seperator, there are some really good IC ones, or a simple single transistor will do the job.

Using a single transistor will also "detect" when voltage is at maximum.

I'll draw a little more to see if I understand this right

 

[Nigel Goodwin]

Using a single transistor will also "detect" when voltage is at maximum.

A single transistor, and before that a single valve, were used as sync-seperators for many years.

That Syncing Feeling!

 

[reader1]

Hi, Nigel,
What mean is your avatar?
Are you interested in Chinese words?

 

[Suraj143]

Thats the point I need sync seperator.

the problem is I don't have special IC's.Thats why I need to do from simple ciruit.

That single transistor solution is a nice idea.But I don't know how to implement.What transistor Do I have to use?

 

[trennonix]

i know that diodes won't pass current if the voltage over them is below a certain level
you might be able to use a diode that won't pass current if the voltage is less than say 0.2V (not that i know if such a diode even exists)
and the signal coming out of the diode will go through a transistor to drive a LED or whatever
and plz do correct me if i'm wrong since i got a pretty basic understanding in electronics

 

[Nigel Goodwin]

Thats the point I need sync seperator.

the problem is I don't have special IC's.Thats why I need to do from simple ciruit.

That single transistor solution is a nice idea.But I don't know how to implement.What transistor Do I have to use?

Look at the link I posted.