Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

ideal transistor is unilateral or not

Status
Not open for further replies.
It depends how do you define the "ideal". People are just trying to make a unilateral transitor but it always comes with the real transistor which is bilateral
 

I guess the ideal transistor is unidirectional (supposed to conduct in one direction)
But in reality, this is not always the case. Consider the use of transistors as switches in power conversion circuits.

If we use a power NPN BJT as a controlled switch (current-controlled) it will conduct current from the collector to the emitter but not in the other direction. If we use a power n-channel MOSFET (voltage-controlled), it will conduct drain to source current through the channel but it can also conduct source to drain by means of a body diode (which is an inherent, parasitic diode-connected BJT).

Please take a look at these slides from Bob Erickson's textbook
which I think will guide you in the right direction.

**broken link removed**

Best regards,
v_c
 

v_c said:
I guess the ideal transistor is unidirectional (supposed to conduct in one direction)
But in reality, this is not always the case. Consider the use of transistors as switches in power conversion circuits.

If we use a power NPN BJT as a controlled switch (current-controlled) it will conduct current from the collector to the emitter but not in the other direction. If we use a power n-channel MOSFET (voltage-controlled), it will conduct drain to source current through the channel but it can also conduct source to drain by means of a body diode (which is an inherent, parasitic diode-connected BJT).

Please take a look at these slides from Bob Erickson's textbook
which I think will guide you in the right direction.

h**p://ece-www.colorado.edu/~pwrelect/book/slides/Ch4slide.pdf

Best regards,
v_c


can we conclude FET as a bilateral device ???
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top