incrementing o/p current

[arin23]

i have an op unity follower as d -ve terminal of my o/p stage.I want my shrt ckt currnt to be 100mA.since an op amp can sink only 10 mA hw can i increase my o/p curnt wid no negative spply available??

 

[Hero999]

Please post a schematic and speak in English not txt talk.

You'll need to add a transistor booster to get 100mA from an op-amp.

 

[arin23]

sorry........have attached the schematic now.
my teacher told that the transistor wont work dis way,probably the positive o/p at op amp o/p terminal wont allow the current to sink in it....
how shd i bias the transistor??
wat shd i do??

 

[arin23]

the attachment is attached here

 

[ericgibbs]

the attachment is attached here

hi,
If I follow what you are trying to do the circuit will not work correctly.

Do you want to control the current from 0mA to 100mA or just switch the 100mA current on and off.???

Please explain what you are expecting the circuit to do.

What is the load for the 100mA current.?

 

[arin23]

100mA is the short ckt current b/w the 2 terminals i have shown in the end.the load is to be connected b/w them.The voltage should not vary with load,as you would know.
I have also come up with another basic idea, what do you say about this??
will the transistor work properly...

 

[ericgibbs]

100mA is the short ckt current b/w the 2 terminals i have shown in the end.the load is to be connected b/w them.The voltage should not vary with load,as you would know.
I have also come up with another basic idea, what do you say about this??
will the transistor work properly...

hi,
I'll look it over and post back.

 

[ericgibbs]

hi,
Simulated your circuit using LTSpice, it dosnt work.

Would you like some suggestions that should make it work or would you prefer to rework it yourself.?