JFET Follower Amplifier Cancels Distortion(Electronic Design)
|1. A JFET follower circuit with a current mirror made up of Q2 and Q4 provides distortion cancellation based on the value selected for RS.|
|2. For the three loads used in these measurements and at 1 V rms, THD+N is below 103 dB at the optimum RS.|
|3. If the ratio of R3/R4 is changed, the required value of RS changes also|
|4. Because of the linear relationship of the output current and input signal created by the circuit, it can be rearranged in the form of an amplifier with a linear transfer function.|
- White, E.L.C., “Thermionic Valve Amplifier Circuit Arrangements,” U.S. patent 2358428, Sept. 19, 1944.
- Taylor, P.L., “Audio Power Amplifier,” Wireless World, June 1973, p. 301.
- Ozawa, O., and Ishikawa, K., “Super Linear Circuit,” 60th AES Convention, May 1980, Preprint No. 1660, pp 1-38.
- Designing With Field-Effect Transistors, ed. by A.D. Evans, McGraw-Hill, New York, 1981, Ch. 3-11, “Distortion in FET Amplifiers.”