Improving on the current mirror
The simple two-transistor current mirror that we saw last time
has problems with its output impedance/voltage compliance and
its accuracy.
This video presents a collection of designs that improve
on its limitations with a few extra components.
Schematics are on the project GitHub:
https://github.com/kennykb/kevins-cave-kludges/tree/main/Transistor101/Ep012-Mirrors
(Yes, I know it says episode 12. I use the same test circuit to evaluate these mirrors.
TIMELINE
00:00 Intro
01:24 Emitter resistors
06:11 Widlar asymmetric mirror
07:35 Wilson mirror
11:32 Symmetric Wilson mirror
14:25 Matched transistor pairs
16:12 Outro
CREDITS
Music:
“Light Sting” Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 4.0 License
http://creativecommons.org/licenses/by/4.0/
Images:
"Barrie Gilbert and George Wilson"
From "George Wilson, Barrie Gilbert speak at next Friday's
engineering seminar." TekWeek, 2 February 1968.
Obtained from https://vintagetek.org/barrie-gilbert/
"Robert Widlar"
Courtesy of National Inventors' Hall of Fame
Used by permission.
DMMT5401 data sheet courtesy of Diodes Incorporated