Solving Electronic Circuits (packed, archive)

 Solve for the gain. Plot frequency response for the following amplifier circuit.

Source

artifact

AI Model Results:

• Grok 4: Share Link (considers parasitic capacitance Cπ ≈ 50 pF, Cμ ≈ 2 pF) - gives (188 kHz)
• Claude: gives 188 kHz, 
• ChatGPT 5: Share Link gives 187 kHz
• Gemini 2.5 Pro: Share Link gives 188 kHz

Note: Lower cut-off comes from coupling capacitors (not shown here). assuming 1.0 μF

Generate professional grade Bode plot.

generate professional plot using Matplotlib

Bode plot

directly from Claude Opus 4.5 (share)

React (Claude) - Python w/Matplotlib -  - Colab - Bode plot

Colab

Bode plot 

1. React (Claude) - AIStudio - Python w/ Matplotlib - Colab - Plot

2. Reasoning (AIStudio) - AIStudio - Python w/ Matplotlib - Colab - Plot

我用Claude計算電晶體放大器，得出頻率響應理論值 2.4 MHz。然後我給他一組Grok 算出來的數據是 125 kHz，兩者差了20倍。

我沒有跟Claude 說這組數據哪裡來的，他稱讚我的數據是應該是用Spice 專業軟體跑出來的，而且提醒我他的計算是根據純理論，因為Spice 可以考慮更多細節去電路模擬，所以Claude認為我的數據比較值得參考。

接下來我跟他講這組數據是 Grok 4 算的，Claude 馬上變換語氣，說頻率響應不可能是125 kHz，業界標準至少在1 MHz 以上，說Grok:

1. Does not make any sense (完全沒有道理）
2. Against common sense (違背常識）
3. Distrust (不值得信賴）

可是剛剛不是還在稱讚「我的模擬」做得好？以前Claude 還會稱讚別家的AI有什麼優勢，現在看起來不演了。

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Amplifier Circuit Analysis

Solve for the gain, plot freq response.

Share (Source)

share (Claude running Python internally on VM)

• Hybrid-π Model, With bypass capacitors, without ignoring base current loading effects on bias networks, Av=-165 (Share including frequency response).
• -194 for Vc vs. Vbase, Ibase ignored (Share)

Gemini 2.5 Pro gain & lower cut off freq match Claude, 4kHz.

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Solve for the gain. Plot frequency response for the following  amplifier circuit.

Source

share (Av=-2.31, Lower Cutoff 20 Hz, Upper Cutoff 10.46MHz)

Analysis with Cπ = 22.1 pF, Cμ = 3.0 pF

20Hz is assumed, not by calculation

Analysis with Cπ = 22.1 pF, Cμ = 3.0 pF: 

• Bode plot, fH = 10.46 MHz, RE not bypassed

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Two-Stage Amplifier Analysis

Solve for the gain, plot frequency response.

Source

Schematic

colab unoptimized (share)

colab optimized (share)

colab increasing C2 from 1 to 10μF (other parameters differ from above)(share)

bypass 47, coupling 10 micro F

(gain approximate)

• Artifact, Share (Cπ2=15 pF, Cμ2=3pF). Result: freq response, gain=8513, low cut off=46.5 Hz, high cut off=312kHz
• Gemini: Result gain=8509, low cut off=46.5 Hz, high cut off=296 kHz @Cπ2=15 pF, Cμ2=3pF (good match!)

Compare

• Artifact, Share. Result: gain=8559 (Hybrid-π Model, With bypass capacitors, without ignoring base current loading effects)
• Artifact. Result: gain=9460 (Ignored base current loading effects)
• comprehensive comparison simplified, do not ignore bias network, do not ignore base current

Can we ask for Bode plot without finding lower/higher cut-off freq?

• You'd better not. (calculated by AIStudio)

Can we be more accurate with cut-off freq? Yes, use transfer function. 296kHz becomes 235kHz. (based on AIStudio)

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Design a Two-Stage BJT Amplifier

Use A* search for optimization. optimal schematic

share

Performance metrics (share)

Use A* to design a class AB amplifier.

The first stage is class A. the second is class B. freq response cut off at 10Hz and 25 KHz

artifact (share)

schematic enhanced by Gemini 3.0 Pro

artifact enhanced by Claude (share)

以上參考答案

(1) -4 (2) 8513 (3) -165 答案誤差10%以內都是正常的

A* vs RL

maze  animate side-by-side 

Circuit

A* 

RL

Comparison (+Circuit)

Urban Traffic

RL

如何分享 Claude 作品 (Artifact, 包含動畫，程式， 圖片，文件...)

 

右上方 有個copy 下拉式選單

選取 Publish 即可

如何分享 ChatGPT連結

 

右上方分享鍵

按壓之後跳出對話視窗

點選複製連結

已分享的連結，會看到 share

https://chatgpt.com/share/699edcfb-2db8-8009-9069-cce6f0a9420a

如果你所提供的連結屬於private chats 連結，只有在該帳號下可以觀看

你無法使用分享的原因，可能是因為你用的是app版，建議你切換到web 版

https://openai.com/

EX#1 Use AI Profesionally

  AI for solving amplifier electronics (課堂講義）

 建議工具

使用 Claude Sonnet 4.6

使用 ChatGPT 5

使用 Gemini 3 Pro 免費額度最高 1M tokens

使用 Grok 4

Content share

• share only link, pure text, markdown (md)
• no attachments accepted, no html, screen dump, or png
• non-compliant homework will be rejected and returned to you

 課堂練習 

Deadline: This Saturday at 23:59

Send all the share links to  me chang212@gmail.com by email with subject EX#1  [your id, your name]

How to publish a Claude artifact

How to share a ChatGPT link

How to share a Grok link

How to share Gemini Link

任選做一題

1. Lab Activity: 為什麼我的 AI 跟你不一樣？

2.  Lab Activity: Amplifier Gain & Frequency Response Using AI-Assisted Analysis 

3. Make the Bode plot of Circuit in Example 1, as below You must verify the results for correctness.

The results must be scientifically accurate.

Topology B in Schematic

4. With the following circuit and its Bode plot

textbook approximations

Think about the prompt used to generate the Bode plot. Why there is level off at high frequencies?

Hints

• Reasoning/Think/Extended Thinking Mode of the AI platform you use may be required for all the problems here

AI 是放大器，不是魔術

yagi uda antenna 3d

yagi uda antenna, near field, maxwell, 3d

yagi uda antenna, near field, array factor, 3d

yagi-uda antenna, array factor, 3d

yagi uda antenna, maxwell numerical, 3d

Electronics, Example 7 (AB, A* Design)

Use A* to design a class AB amplifier. The first stage is class A. the second is class B. freq response cut off at 10Hz and 25 KHz

artifact (share)

schematic enhanced by Gemini 3.0 Pro

artifact enhanced by Claude (share) opus 4.5

A* optimized formulation

artifact, share 

A* optimizaed

Electronics, Example 6 (2Stage, A*))

 

Design a Two-Stage BJT Amplifier (Parameters to optimizeRE1, RC1. RE2. RC2)

advanced version A* search for optimization, share 4-parameter

A* 8-parameter

_______________________________________________

demo, no A*

A* search for optimization. share

advanced version A* search for optimization, share

A*  8 parameters (resistors)

Electronics, Example 5 (2Stage)

 

Two-Stage Amplifier Analysis

Solve for the gain, plot frequency response.

Circuit parameters 

Opus 4.6 extended. exact, transfer function, −3 dB crossing at 77 Hz, parameters as above original

Gain is 7943=78.0 dB considering Early voltage. 8511=78.6dB ignoring it.

exact transfer function vs. factored transfer function

bypass 47, coupling 10 micro F

(gain approximate)

_________________________________________________________________________

• Artifact, Share (Cπ2=15 pF, Cμ2=3pF). Result: freq response, gain=8513, low cut off=46.5 Hz, high cut off=312kHz
• Gemini: Result gain=8509, low cut off=46.5 Hz, high cut off=296 kHz @Cπ2=15 pF, Cμ2=3pF (good match!)

colab optimized (share)

Can we be more accurate with cut-off freq? Yes, use transfer function.  (based on AIStudio)

Compare

• Artifact, Share. Result: gain=8559 (Hybrid-π Model, With bypass capacitors, without ignoring base current loading effects)
• Artifact. Result: gain=9460 (Ignored base current loading effects)
• comprehensive comparison simplified, do not ignore bias network, do not ignore base current