Linear Voltage Regulator Design

[cyw1984]

**broken link removed**

If I want to output 0-30V

Vin = 40V , Is it OK?

1 to 5 should use which component????

how to caculate this??

Also....How can this circuit improve the output stable and accurate with Vref controlled by DAC......

 

[kwkam]

1 and 2 are darlington NPN, 3 is PNP.
3 with 1 & 2 form a peuso PNP which have large beta and can handle larger current.
4 is common NPN and 5 is resistor to limit base current to 4.
You can add some capacitor between opamp output and -ve input to keep loop stable.

 

[cyw1984]

1 and 2 are darlington NPN, 3 is PNP.
3 with 1 & 2 form a peuso PNP which have large beta and can handle larger current.
4 is common NPN and 5 is resistor to limit base current to 4.
You can add some capacitor between opamp output and -ve input to keep loop stable.

HOW TO ADD SOME CAPACITOR??

 

[carrier]

5- is not very important by it can supply the maximum current base.
1- must be chosen so that to deliver max power and current when vin=40 volt and vout =0 and suppose iout =1 amp the trasistor 1 must Ic=5amp and Pt=2.5*40*1=100w such as 2n3055
2- must be drive the base of 1 if beta are 20 for 2n3055 the base current is 1amp/20=50ma so this transistor such as bd139
3- must be chosen so that drive the base of 2 so it bc237 pnp transistor
4-bc547

 

[cyw1984]

5- is not very important by it can supply the maximum current base.
1- must be chosen so that to deliver max power and current when vin=40 volt and vout =0 and suppose iout =1 amp the trasistor 1 must Ic=5amp and Pt=2.5*40*1=100w such as 2n3055
2- must be drive the base of 1 if beta are 20 for 2n3055 the base current is 1amp/20=50ma so this transistor such as bd139
3- must be chosen so that drive the base of 2 so it bc237 pnp transistor
4-bc547

**broken link removed**

O....thanks a lot~~~
But bc237 is a NPN transistor!!
Then, how to add anything to stable this circuit and accurate of the DAC input effect the output??
what is the value of resistor to limit base current to bc547
may I put 2K??

 

[cyw1984]

Someone can help me???
urgent

 

[cyw1984]

**broken link removed**
It is my new design for my circuit

I hear LM358 is slow op-amp...which opamp should I use in this cirucit???


Also, how to add on somthing to improve this circuit . Such as capicator to reduce noise and zener diode make the voltage stable???

Thanks a lot