DCBias-MOSFET

# DCBias-MOSFET - D =5K R S = 1K V G =5 and V DD =15 V T =1...

This preview shows page 1. Sign up to view the full content.

How to approach DC bias MOSFET problem solving: 1. If not obvious, assume transistor is saturated. (80% of the time it is.) 2. Compute V G – Remember I G =0. 3. Write a loop equation thru source. 4. Solve the quadratic equation. 5. Check for V GS that is logically the correct answer. 6. If saturation is confirmed, calculate the unknown and stop. 7. If not, rework using the ohmic region (triode) equation. Example. Given: N channel MOSFET with R
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: D =5K, R S = 1K, V G =5, and V DD =15. V T =1 and μC(w/L) =0.5 mA/V 2 Find the drain current and source and drain voltages. Solution: V S = I D * R S => Where I D = 0.5K (V GS- V T ) 2 if saturated. Also remember that V GS = V G- V S V S = 10.5 or 1.5 are the solutions to the quadratic equation. Only 1.5 is the logical solution. I D = 0.25(5-1.5-1) 2 = 1.56mA Thus: VD = 15 – 5K*1.56mA = 7.2 volts....
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online