Public info about the author: Cribald

Electronics engineer graduated at Università Politecnica delle Marche in Ancona. Experience in software and hardware designing. PSpice user since the days of university studies.
  • This simulation with OrCAD PSpice 16.6 , shows a simple and elegant method to analyze the stability of a 3-stage amplifier with feedback applied as the compensation capacitors vary. This method is applied to the 200 Watt Mosfet Power Amplifier AL-35.
    We ‘ll see how to estimate the phase margin with Bode diagrams and how the compensation capacitors affect the phase margin and the frequency response of the amplifier gain.

  • Spice simulation with OrCAD PSpice of a 200Watt Power mosfet amplifier Zestaw AL-35. A 3 stage power amplifier with 2 N-channel Mosfet IRFP240 and 2 P-channel IRFP9240. IRFP9240 models in IRF and PWRMOS libaries are not suitable for performing the simulation correctly, new IRFP9240 models have been imported
    .The BD139 NPN transistor model and the medium power PNP transistor MJE350 model are missing in the default PSpice libraries. All the models are inside the .zip file. For adding all .lib and .olb libraries read the readme.txt file.

    • 1khztransientanalysisR-d0c28e4a ACsweepR-2b152429 FFTtransientoutputR-1f2f1d35 parametricanalysisSETpotentiometerR-eda0a54e al_35_schema_167-809b56fb al_35_bottom_183-0fc51764
  • A full course using PSpice as SPICE simulator for a practical and easy way to learn 3-stage audio power amplifiers design with theory and SPICE simulation analysis. You ‘ll learn to calculate and size components of a basic three stage power amplifier. The sources current circuits of the first stage, study the effects of a feedback signal application, the mirroring of the first stage currents, design of a typical dual rail power supply for a fixed power, features of enhanced output stages with a current limiter, a zobel network filter, Nyquist Criterion to validate the stability of the amplifier with a feedback applied. The course explains how to implement frequency compensation with one or two dominant poles with compensation capacitors, design of top quality BJT 100W quasi complementary class B, 100W complementary class B, 140W class B, 40W class A.

    • 3 stages base schematic dual power supply 100W complementary class B 100W quasicomplementary class B class A 40W amplifier class B 140W amplifier dual power supply rectified global view simulation of dual power supplay gain phase bode plot without compensation gain phase bode plot after compensation phase out of stability region 70 degrees phase margin
  • SPICE simulation of a very high quality BJTs power amplifier in class A. Three stages, class A amplifier, double simmetrical differential couple with current mirrors. Sources currents with automatic control of the constant current amplitude. Feedback circuit and couple of compensation capacitors for every differential couple of the first stage. Darlington and cascode configuration transistors in the intermediate stage. Complementary parallel final transistors in emitter follower configuration, and SOAR circuit with double slope limiter circuit.

    • mirror effect on bjt emitters currents class A quiescent final bjt currents final BJT currents input output waveforms Gain versus frequency
  • SPICE simulation of a an active low pass filter in voltage follower configuration. How sizing the component values to set the cutoff frequency.

    • low pass filter response with unitary gain