transistor parallel operation ??????

[rishigzb]

how can we connect 6 transistor in parrallel???

 

[ericgibbs]

how can we connect 6 transistor in parrallel???

hi,
Its possible, but it depends upon the circuit.?

 

[rishigzb]

what are the condition for parrallel operation of transistor???

 

[ericgibbs]

what are the condition for parrallel operation of transistor???

Its not possible to say what the conditions are, unless I can see your circuit.???

 

[Grossel]

what are the condition for parrallel operation of transistor???

Hu? That question makes sense only if somebody other ask.
What is the condition? (you're the only one here that can answer)

And the magic wizard haven't being around for years, so I doubt he can provide any help

 

[ronsimpson]

Transistors do not play well together. If you connect the B.s together and the C.s together and the E.s together they will not share current.

If each transistor had its own emitter resistor, and the resistors had 0.3 volts (or more) across them at full load then they do some sharing. At 0.6V on the emitter resistors they play together fine. The transistors need to be at the same temperature. (on the same heat sink)

 

[crutschow]

Transistors do not play well together. If you connect the B.s together and the C.s together and the E.s together they will not share current.

If each transistor had its own emitter resistor, and the resistors had 0.3 volts (or more) across them at full load then they do some sharing. At 0.6V on the emitter resistors they play together fine. The transistors need to be at the same temperature. (on the same heat sink)

That's for bipolar transistors. But MOSFET transistors can have a significant difference in Vgs for the same current which makes balancing them even more difficult.

 

[Grossel]

That's for bipolar transistors. But MOSFET transistors can have a significant difference in Vgs for the same current which makes balancing them even more difficult.

A dirty solution for this might be using same number of opamps to get each mosfet be part of their own feedback system.
Still, an emittor resistor is needed.

 

[ronsimpson]

Before we got too complicated we need to know what transistors he is talking about. (bipolar or MOSFET)

 

[Roff]

That's for bipolar transistors. But MOSFET transistors can have a significant difference in Vgs for the same current which makes balancing them even more difficult.

Here is a heavy duty treatise on that topic.
And this is about using MOSFETs as switches. In analog applications, it gets even hairier.