BJT Driving Circuit

[Shikantroo]

I am will be very much thankful if anyone can help me with the design of triggering of 6 BJT in such a way that all the switches need to either block two times the input voltage or block both positive and negative voltages.

Waiting for the response

 

[alec_t]

What is the source of the 'input' voltage? Is the 'input' AC or DC? Is the 'input' what controls the BJTs, or something to be passed to an output? What load will the BJTs drive?

 

[Shikantroo]

The Input to the BJTs' are DC voltage source , and BJT are used a switching device to charger the capacitor in parallel way such that each capacitor have voltage stored equal in value to the input DC voltage.

 

[Norator]

To avoid smoking your transistors do the I = C dV/dT calculation first. Almost certainly you'll need some form of current limiting.

 

[Shikantroo]

I just need help in the context " How I should switch the BJT in such a way" that they charge the corresponding capacitor equal to the input DC voltage. After that I will use some current limiting phenomenon.

 

[alec_t]

Blocking both +ve and -ve DC voltages will require more than a single BJT per cap, unless the -ve voltage is less than the reverse breakdown voltage of the BJT. What voltage will you be switching?

 

[Shikantroo]

Per capacitor there are 2 BJTs (I have mentioned that the number of BJTs are six and number of capacitors are 3) , and the voltage at which BJT should be switched can be varied from 1 to 1.5V.

Regards

 

[alec_t]

the voltage at which BJT should be switched can be varied from 1 to 1.5V.

Is that the control voltage (base voltage) for the bjt or the voltage to which you want to charge the caps?

 

[Shikantroo]

This is the control voltage (base voltage) for the BJT.

 

[alec_t]

And what voltage do you want to charge the caps to?

 

[Shikantroo]

Upto the input voltage level, e.g 5V

 

[Shikantroo]

Upto the input voltage , means 5V, In such a way that the voltages of each capacitor get added and give 15V.

 

[ChrisP58]

Upto the input voltage , means 5V, In such a way that the voltages of each capacitor get added and give 15V.

So the three capacitors are in series? To do that, you will either need three isolated 5 volt sources, or you will need 15 volts.

Or is your intent to charge them in parallel with a single 5V source, and then change to a series connection so that you have 15Volts?

 

[Shikantroo]

I intent to charge them in parallel with a single 5V source, and then change to a series connection so that you have 15Volts

 

[Shikantroo]

So the three capacitors are in series? To do that, you will either need three isolated 5 volt sources, or you will need 15 volts.

Or is your intent to charge them in parallel with a single 5V source, and then change to a series connection so that you have 15Volts?

I intent to charge them in parallel with a single 5V source, and then change to a series connection so that you have 15Volts

 

[ChrisP58]

If what you are trying to do is just get 15 Volts out from a 5 Volt source, there are simpler ways. How much power do you need at 15V?

 

[Shikantroo]

I am trying to do in the way , I have stated , There might be many other simpler ways too.

 

[ChrisP58]

It can be done that way, but we still need to know how much power you need at the output.

 

[Shikantroo]

Power needed at the output is 5kW.

 

[audioguru]

WHAT?? Watt??
5kW is 5000 Watts which is a lot of power.
Very good and huge capacitors can supply 5000 Watts for only a few micro-seconds. Then you charge the capacitors and they produce 5000 Watts for another few micro-seconds.