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| 3.3 MOSFET I-V Modelling |
We are interested in finding the output characteristics ( ) and the transfer charcteristics ( ) of the MOSFET. In other words, we can find out both if we can formulate a mathematical equation of the form : |
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| Intutively, we can say that voltage level specifications and the material parameters cannot be altered by designers. So the only tools in the designer's hands with which he/she can improve the performance of the device are its dimensions, W and L (shown in top view of MOSFET fig 2). In fact, the most important parameter in the device simulations is ratio of W and L. |
| The equations governing the output and transfer characteristics of an n-MOSFET and p-MOSFET are : |
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p-MOSFET: |
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Linear
Saturation |
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n-MOSFET: |
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Linear
Saturation |
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