Electronics Technology - CaoThang Technical College, VietNam

18/02/2026

10/01/2026

https://www.facebook.com/share/p/1C3LgEYviL/

04/01/2026

https://www.facebook.com/share/p/1CQ18egv8U/

In an audio amplifier, the loudspeaker does not behave like a pure resistor. At low frequencies it shows a resonance peak, and at high frequencies its voice-coil inductance causes the impedance to rise. The LM386 output stage is stable only when it sees a reasonably predictable load. Without compensation, this rising impedance can cause high-frequency ringing, distortion, or even oscillation.
The Zobel network, made of a resistor and capacitor in series from the output to ground, solves this problem. At low audio frequencies the capacitor has high reactance, so the network has almost no effect. As frequency increases, the capacitor’s reactance drops and the resistor becomes dominant, forcing the amplifier to see a nearly resistive load. This flattens the impedance curve at high frequencies and damps unwanted resonances.
In this circuit, the 0.05 µF capacitor and 10 Ω resistor form a standard Zobel network recommended for the LM386. The impedance graph correctly shows that, without the Zobel network, impedance rises sharply with frequency, while with the network it remains relatively flat. This improves stability, reduces noise, and ensures cleaner audio output across the full frequency range.

17/11/2025

03/11/2025

FPGA vs CPU

17/10/2025

https://caothang.edu.vn/en/Interview-And-Recruitment-Event-For-Module-Equipment-Technician-Position-Intel-Products-Vietnam-At-Cao-Thang-Technical-College.html

In the context of the semiconductor industry playing a central role in the global technological revolution, the collaboration between academia and industry has become a strategic direction in developing a high-quality technical workforce — individuals who master knowledge and are ready to conquer ...

08/05/2022

Great invention

29/03/2022

Architecture for a PLC - SIMATIC S7 series

18/03/2022

RECTIFIER

15/03/2022

Active & Passive Electronic Components