A short tutorial on the basics of the Gilbert Cell - a very popular analog four-quadrant multiplier circuit that has a wide variety of applications ranging from variable gain amplifiers to mixers and balanced modulators. The video is light on the math, focusing mainly on delivering a practical, intuitive understanding of how the circuit operates. It is highly recommended that the viewer be familiar with the basic operation of a differential-pair. Video #193 (linked below) would be a good thing to review to freshen up on the diff-pair operation.

Lecture on Translinear Circuits by Barrie Gilbert himself:
   • Bipolar Translinear Circuits, lecture...  

Differential Pair video:
   • #193: Back to Basics: the differentia...  

Show notes for this video:
http://www.qsl.net/w2aew/youtube/Gilb...