This preview shows page 1. Sign up to view the full content.
Unformatted text preview: I
2
I
I C 2 = EE − ΔI
2
ΔI C1 = g m ( ΔV − ΔVP )
I C1 = ΔI C 2 = g m ( −ΔV − ΔVP )
ΔI C1 = −ΔI C 2
⇒ ΔVP = 0
EE105, Fall 2013 Lecture 22 – Slide 14 Prof. Ming C. Wu 7 Extension of Virtual Ground §༊ It can be shown that if R1 = R2, and the voltage at node A goes up by the same amount that the voltage at node B goes down, then the voltage at node X does not change. vX = 0 EE105, Fall 2013 Lecture 22 – Slide 15 Prof. Ming C. Wu Small Signal Diﬀeren?al Gain §༊ Since the output signal changes by  2gmΔVRC when the input signal changes by 2ΔV, the small signal voltage gain is –gmRC. §༊ Note that the voltage gain is the same as for a CE stage, but that the power dissipa?on is doubled. Av = EE105, Fall 2013 Lecture 22 – Slide 16 − 2 g m Δ...
View
Full
Document
 Fall '07
 KingLiu
 Amplifier, Frequency

Click to edit the document details