In the last video, I explained the WHY behind the CASCODE configuration and the HOW it works behind its operation. Here is a LINK to that video if you missed it:
https://youtu.be/j3r0-3vYkO4
In this video I will be showing you how to design one. I will walk through the entire design process including all of the assumptions, rules of thumb and engineering estimates needed to make this work.
I will also demonstrate the benefits of this configuration both in the simulation world and with a bench experiment.
LINK to the "Go-Along-With-The-Video" formula sheet:
https://drive.google.com/file/d/1uzO3a4mXY2uli8bmabFcdhMsybLnG88g/view?usp=drive_link
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Time Markers for Your Convenience
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00:05 Introductory Comments
01:18 Establish Design Goals
03:00 Calculating Transistor Currents
05:31 Calculate Re
06:46 Calculate Q2's Base Voltage
07:55 Calculate R1, R2 (Rb3), Rth, Vth (Thevenin Stuff)
07:55 Introduction to the Thevenin Stuff (a reminder)
08:45 Calculate Rth
09:31 Calculate V(Rth)
10:21 Calculate Vth
11:36 Calculating R1 & R2
11:43 Calculate R1
12:20 Calculate R2
13:14 Calculating the Currents in the Bias Resistor Chain
13:21 Calculating I(Rb3)
14:12 Calculating I(Rb2)
15:41 Calculating I(Rb1)
17:21 Unstucking the Stuck with Engineering Knowledge (V(Rb2))
19:16 Calculating the Rest of the Bias String (Rb2 & Rb1)
19:16 Calculating Rb2
19:58 Calculating V(Rb1) so we can find Rb1
21:16 The Value of Rb1 by Ohm's Law
22:03 The Conundrum ... Solved
24:05 Calculating Vcq so we can find Rc
26:44 Calculating V(Rc)
27:11 Calculating Rc
28:19 Calculating the Anticipated Gain
30:32 Performance Evaluation
30:33 Using LTSpice Simulation
33:18 The Bench - Breadboard Results
35:17 Final Comments and Toodle-Oots