Hi all

The ic is 555 timer generate maximum 1 khz square wave
The diode is 1n4148
The combination of the Dodie rlc what and how works

Thanks in advance

 

Doesn't seem to do much at all other than charge a capacitor.

 

The diode and 1K resistor look to be configured as flyback for the coil. Unless the diode anode goes more positive than the cathode the diode will never be forward biased. What exactly is the coil? The inductor (coil) and capacitor form a series LC circuit. The coil inductance is unknown? If the cap were not in series with the coil and the transistor was maybe an old 2N3055 I would have guessed an ignition coil test circuit but the cap is in there forming a series LC circuit.

Ron

 

The diode and 1K resistor look to be configured as flyback for the coil. Unless the diode anode goes more positive than the cathode the diode will never be forward biased. What exactly is the coil? The inductor (coil) and capacitor form a series LC circuit. The coil inductance is unknown? If the cap were not in series with the coil and the transistor was maybe an old 2N3055 I would have guessed an ignition coil test circuit but the cap is in there forming a series LC circuit.

Ron

Hi

Thanks for your response the transistor 2n 3904

And the coil is not critical value

 

Doesn't seem to do much at all other than charge a capacitor

Hi

Can you explain more and what the use of the resistance and Diode in such manner

 

What are you wanting to do with it?

 

What are you wanting to do with it?

I have found it inside laser diode I just want to understand it

 

Have you drawn it correctly?

 

Hi

Thanks for your response the transistor 2n 3904

And the coil is not critical value

Well then the 2n3904 is a common switching NPN transistor with a max current of about 200 mA if I recall correctly. The 103 labeled is a ceramic disk of 10,000 pF. I don't see where the 1N4148 will ever be forward biased? Less knowing the inductor value I am not sure what the circuit is supposed to do.

Ron

 

Hi

Thanks for your response the transistor 2n 3904

And the coil is not critical value

If you don't know what the circuit is, what it does, or how it works, how do you know that the value of the coil isn't critical?

 

If you don't know what the circuit is, what it does, or how it works, how do you know that the value of the coil isn't critical?

I am asking to get knowledge not get evaluation from you

I know that the coil is not critical because I saw the circuit many times and each time the coil vary in length it was much more useful if you explained about the circuit rather than evaluate people

 

Have you drawn it correctly?

Yes it's correct drawing

 

I have found it inside laser diode

Where does the circuit shown connect to the laser diode semiconductor section terminals?

 

Where does the circuit shown connect to the laser diode semiconductor section terminals?

I don't know where the laser diode terminal's connected It is 5 volt laser diode but i think one with positive terminal of the coil on main dc line and the other to the transistor emitter terminal I think the circuit change the current of the laser diode or making sort of modulation

 

Hi all

The ic is 555 timer generate maximum 1 khz square wave
The diode is 1n4148
The combination of the Dodie rlc what and how works

Thanks in advance
View attachment 290559

How does that 103 capacitor ever discharge?

 

How does that 103 capacitor ever discharge?

The capacitor and series inductor "ring" at their LC frequency with the voltage fading each time the 555 turns off the transistor.

 

Somehow, I doubt that the circuit is correct as drawn. There is no DC path through the transistor. But then we don’t know where the laser diode is connected.

 

Somehow, I doubt that the circuit is correct as drawn. There is no DC path through the transistor. But then we don’t know where the laser diode is connected.

Correct. If the laser diode has no current limiting then it quickly burns out.

 

Correct. If the laser diode has no current limiting then it quickly burns out.

The laser diode has built In current resistor it's working on 5 volt and circuit works on 5 volt

 

The laser diode has built In current resistor it's working on 5 volt and circuit works on 5 volt

How is it connected to the circuit you posted? Without it, the circuit makes no sense.