MOSFET I-Vg Curve: Which Curve is Impossible?

  • Thread starter Thread starter zhangz64
  • Start date Start date
  • Tags Tags
    Curve Mosfet
Click For Summary

Discussion Overview

The discussion centers around the I-Vg curves of MOSFETs, specifically identifying which of the presented curves is impossible based on their characteristics. The scope includes theoretical analysis and homework-related inquiry.

Discussion Character

  • Homework-related, Debate/contested, Technical explanation

Main Points Raised

  • One participant suggests that curve 1 is likely impossible due to an unlikely sharp transition from the subthreshold to the quadratic region.
  • Another participant expresses confusion, indicating that both curve 1 and curve 5 could be considered impossible.
  • A different participant asserts that curve 1 represents infinite gain, making it clearly impossible.
  • Curve 5 is noted by multiple participants as resembling reverse breakdown due to electron tunneling, raising questions about its validity.
  • One participant emphasizes that tunneling cannot occur with zero Vgs, challenging the feasibility of curve 5.

Areas of Agreement / Disagreement

Participants express differing views on which curve is impossible, with no consensus reached. Some support the impossibility of curve 1, while others highlight concerns regarding curve 5.

Contextual Notes

Participants do not fully resolve the implications of the curves, and assumptions regarding the characteristics of MOSFET behavior are not explicitly stated.

zhangz64
Messages
2
Reaction score
0
Homework Statement
Below graph shows the I - Vg curve for different MOSFET, which curve is impossible for MOSFET?
Relevant Equations
I - Vg
Homework Statement: Below graph shows the I - Vg curve for different MOSFET, which curve is impossible for MOSFET?
Homework Equations: I - Vg

I am inclined to select 1), as it is not likely to have a sharp transition from subthreshold to Quadritica region. However, graph 5 also looks strange, since it somehow shows current in at subthreshold region. I am therefore confused about whether it should be 1) or 5).
 

Attachments

  • Screen Shot 2019-08-14 at 11.02.48 PM.png
    Screen Shot 2019-08-14 at 11.02.48 PM.png
    16.9 KB · Views: 449
Physics news on Phys.org
I would agree. Could be either.
 
Tom.G said:
Curve #5 reminds one of reverse breakdown (due to Electron tunneling) of the gate oxide.
You can't tunnel with zero Vgs!
 

Similar threads

How to determine drain-source voltage for this MOSFET amplifier.
  • · Replies 0 ·
Replies
0
Views
2K
Mosfet equation: how to get it?
  • · Replies 6 ·
Replies
6
Views
2K
Engineering Biasing circuit with a MOSFET: am I missing something
  • · Replies 1 ·
Replies
1
Views
2K
Optimizing Mosfet Amplifier Problem Solution with Kirchhoff's Law and KVL
  • · Replies 13 ·
Replies
13
Views
3K
Engineering Velocity Decay Curve for a Rocket
  • · Replies 4 ·
Replies
4
Views
2K
MOSFET inverter that satisfies a given static discipline
  • · Replies 1 ·
Replies
1
Views
4K
Solve MOSFET Confusion: Establish 0.8mA & 1.5V with Parameters VT, μpCox, L, λ
  • · Replies 9 ·
Replies
9
Views
2K
Engineering Why Does Vout Become Constant in a MOSFET Circuit at High Vin?
  • · Replies 1 ·
Replies
1
Views
4K
Question about MOSFET Saturation region
  • · Replies 7 ·
Replies
7
Views
3K
Voltage gain for Common Source Degenerative MOSFET
  • · Replies 8 ·
Replies
8
Views
10K