Switched-Capacitor Amplifier Design: How does it work?

[@STEMprof]

Thanks for watching. For more Op Amp Circuits please see: Instrumentation Amplifier with Electronic Gain Control kzbin.info/www/bejne/eWXXmJuQYtZpkNU Differential Amplifier Design with BJT transistors kzbin.info/www/bejne/sHzKhIysoJx9d68 Power Amplifier Design (Class A) with Transformer kzbin.info/www/bejne/nXzPe6WnfNaYeas Op Amp Analog Computer Differential Equation Solver kzbin.info/www/bejne/e3_UZGx7mtiZhtk Thermometer Circuit Design with Op Amp & BJT transistor kzbin.info/www/bejne/a2a8pKWXe6pjqMk Push-Pull Power Amplifier with Darlington Transistors kzbin.info/www/bejne/bmeZfoyfl9Rrr6c Analog Logarithm Computer kzbin.info/www/bejne/iKGudqRrjN6igsk Sawtooth Oscillator Design kzbin.info/www/bejne/aJa4pHqGm9aVjZY Triangle Oscillator Op Amp circuit kzbin.info/www/bejne/gHeYhqOVmNp_b80 Sallen-Key Analog Filter Design Tutorial kzbin.info/www/bejne/gai4n4SOl9Bqna8 How to find Bode Plot, Freq Response, Transfer Function of Analog Filters kzbin.info/www/bejne/rIupnIObecZkfpo Universal Analog Filter Design kzbin.info/www/bejne/aHuQYaCpjb94aNE Laplace Transform Example and S-domain circuit analysis: kzbin.info/www/bejne/pqSbf2iKhbKSp7c Op Amp circuit Bode Frequency plot kzbin.info/www/bejne/eH25q6irpqafkNU Lowpass Butterworth Filter: kzbin.info/www/bejne/i6umm56tpt5gb9k Analog Computer to Raise Signal to power n kzbin.info/www/bejne/f4a3nXV-Zrqll6c Differential Equation Solver Analog Circuit kzbin.info/www/bejne/iGS7ZnSPg796e6s Complex Sinusoid Oscillator kzbin.info/www/bejne/fYm1maCtorhokM0 Full-Wave Rectifier circuit example kzbin.info/www/bejne/enutfoGLYqiMmck Sawtooth Waveform Generator design with OpAmp, JFET, BJT kzbin.info/www/bejne/a6uriYeuYrufaJI op amps Circuit with feedback loops to design an analog computer that solves a second order differential equation kzbin.info/www/bejne/fpa9g6ekh72je6s For more analog circuits and signal processing examples see: kzbin.info/aero/PLrwXF7N522y4c7c-8KBjrwd7IyaZfWxyt I hope these Circuit design and analysis videos are helpful. 🙂

[@AjinkyaMahajan]

Thanks for the wonderful explanation. I was searching for SC content from long time. Cheers!!

[@STEMprof]

You're welcome! Thanks for watching. Glad that this switched-capacitor amplifier tutorial is useful. For more circuits please see: Op Amp Analog Computer Differential Equation Solver kzbin.info/www/bejne/e3_UZGx7mtiZhtk Instrumentation Amplifier with Electronic Gain Control kzbin.info/www/bejne/eWXXmJuQYtZpkNU Thermometer Circuit Design with Op Amp & BJT transistor kzbin.info/www/bejne/a2a8pKWXe6pjqMk Push-Pull Power Amplifier with Darlington Transistors kzbin.info/www/bejne/bmeZfoyfl9Rrr6c Analog Logarithm Computer kzbin.info/www/bejne/iKGudqRrjN6igsk Sawtooth Oscillator Design kzbin.info/www/bejne/aJa4pHqGm9aVjZY Triangle Oscillator Op Amp circuit kzbin.info/www/bejne/gHeYhqOVmNp_b80 I hope these Circuit Analysis videos are interesting 🙂

[@sahryun]

Nice and well-understood.

[@STEMprof]

Thank you for watching. Glad that this switched capacitor amplifier design tutorial is useful. For more circuits please see: Thermometer Circuit Design with Op Amp & BJT transistor kzbin.info/www/bejne/a2a8pKWXe6pjqMk Op Amp Analog Computer Differential Equation Solver kzbin.info/www/bejne/e3_UZGx7mtiZhtk Instrumentation Amplifier with Electronic Gain Control kzbin.info/www/bejne/eWXXmJuQYtZpkNU Push-Pull Power Amplifier with Darlington Transistors kzbin.info/www/bejne/bmeZfoyfl9Rrr6c Analog Logarithm Computer kzbin.info/www/bejne/iKGudqRrjN6igsk Sawtooth Oscillator Design kzbin.info/www/bejne/aJa4pHqGm9aVjZY Triangle Oscillator Op Amp circuit kzbin.info/www/bejne/gHeYhqOVmNp_b80 I hope these Circuit videos are interesting 🙂

[@souravnandi6162]

Wonderful explanation sir

[@STEMprof]

Thank you! Glad that you liked this switched-cap video. Here are a few related videos: Instrumentation Amplifier with Electronic Gain Control kzbin.info/www/bejne/eWXXmJuQYtZpkNU Push-Pull Power Amplifier with Darlington Transistors kzbin.info/www/bejne/bmeZfoyfl9Rrr6c Analog Logarithm Amplifier kzbin.info/www/bejne/iKGudqRrjN6igsk I hope these Circuit videos are interesting 🙋‍♂️

[@sathyadevcherala3347]

I want to simulate this on Pspice can u give values capacitors and clock frequency and any other changes required or any things to keep in mind???

[@STEMprof]

Depends on your target application. In case of Audio Signal Processing, the signal frequency range is ~50 Hz to 20 kHz. So, I suggest you select your clock frequency conservatively say 400 kHz. Capacitors in the range of ~5nF to 10nF should be fine assuming switch-on resistance of NMOS transistor less than 100 Ohms (check your transistor datasheet). To be on the safe side, your NMOS switching transistors should have a max switching frequency of at least a few MHz. Lastly, given the clock frequency is not high, conservatively select a zero offset low noise CMOS Op Amp with a slew rate 20 times faster than your clock frequency. For example, if your clock rate is 400 kHz, then select Op Amp with slew rate of peak-peak (say 5 volts) per 100 ns or faster. More op amp amplifier videos are published in the kzbin.info/aero/PLrwXF7N522y5679YAO-lFrNVYqV9XMNTr playlist. I hope this is helpful.

[@Chupacabras222]

Very interesting. What's the switching noise? Is the output usually filtered somehow?

[@STEMprof]

Thanks for watching and your comment. Glad that you like this switched-capacitor amplifier design video. To your point, switching noise and clock non-idealities are important practical considerations in switched-cap circuit design. I'll post more examples in the analog playlist below. Examples of such non-idealities are flicker and shot noise, parasitic capacitance and charge sharing between the switches and circuit nodes, clock feedthrough, charge injection, clock Jitter, Skew, drift etc. Depending on circuit type and target design KPIs, there are number of noise reduction techniques for switched-capacitor circuits to reduce or compensate clock/switch non-idealities. Examples of such techniques include use larger capacitors, higher clock frequencies (oversampling), better matched transistors, noise shaping, noise modulation using Delta-sigma modulation, or filter noise by using proper filters in either the continuous or discrete-time domain. These are extensive topics that require dedicated examples and video. For more analog circuit examples please see: Op Amp Analog Computer Differential Equation Solver kzbin.info/www/bejne/e3_UZGx7mtiZhtk Instrumentation Amplifier with Electronic Gain Control kzbin.info/www/bejne/eWXXmJuQYtZpkNU Thermometer Circuit Design with Op Amp & BJT transistor kzbin.info/www/bejne/a2a8pKWXe6pjqMk Push-Pull Power Amplifier with Darlington Transistors kzbin.info/www/bejne/bmeZfoyfl9Rrr6c Analog Logarithm Computer kzbin.info/www/bejne/iKGudqRrjN6igsk Sawtooth Oscillator Design kzbin.info/www/bejne/aJa4pHqGm9aVjZY Triangle Oscillator Op Amp circuit kzbin.info/www/bejne/gHeYhqOVmNp_b80 kzbin.info/aero/PLrwXF7N522y4c7c-8KBjrwd7IyaZfWxyt I hope this is helpful. 🙂

[@estebeer]

C2 also works as an offset compensation of the opamp

[@STEMprof]

Good point! Thanks for your interest and for sharing your insights.

[@sathyadevcherala3347]

Say I want to do physical circuit on this What components should i use? I made one using 2n7000 mosfet,freq-1khz,Lm324 opamp,Cap-47pf,100pF Its not really working???can u help

[@STEMprof]

Depends on your target application. Say, for Audio Signal Processing, the signal frequency range is ~50 Hz to 20 kHz. So, a clock frequency of say 500 kHz or higher should be proper. Capacitors in the range of ~5nF to 10nF should be fine assuming switch-on resistance of NMOS transistor less than 100 Ohms (check your transistor datasheet). To be on the safe side, your NMOS switching transistors should have a max switching frequency of at least a few MHz. Lastly, given the clock frequency is not that high, conservatively select a zero offset low noise CMOS Op Amp with a slew rate 20 times faster than your clock frequency. For example, if your clock rate is 500 kHz, then select Op Amp with slew rate of peak-peak (say 5 volts) per 100 ns or faster. See more amplifier videos in kzbin.info/aero/PLrwXF7N522y5679YAO-lFrNVYqV9XMNTr op amp amplifiers videos playlist.

[@nafiuranik7598]

How can i simulate this circuit in proteus can u give me the all components name sir kindly?

[@STEMprof]

@nafiuranik7598 Glad that you found this switch cap amplifier circuit tutorial useful. It depends what applications you are targeting. If it is Audio Signal Processing, then Your frequency range of interest is between 50 Hz to 20 kHz. I suggest clock frequency conservatively between 200 to 400 KHz. Then, given the clock frequency is not high, conservatively select an Op Amp that has a slew rate 20 times faster than your clock frequency. For example, if your clock rate is 400 kHz, then select Op Amp with slew rate of roughly peak-peak V (say 5 volts) per 100 ns or faster. Your NMOS transistors should also be comfortably able to work at few MHz rate. More op amp amplifier examples and videos are posted in kzbin.info/aero/PLrwXF7N522y5679YAO-lFrNVYqV9XMNTr playlist. I hope this is helpful.

[@nafiuranik7598]

​@@STEMprofhow can i use switch capacitor common mode circuit to mitigate its noise?

[@STEMprof]

That's a good question and practical concern. I suggest using a zero offset very low noise CMOS op amp.

[@sc0or]

We can divide an output signal by 100 and then use 20k resistor to get an overall gain of 200. So, we will have 10k, 20k, 100, and 10K, and no problem with a space on a chip (and a thermal noise) I think

[@STEMprof]

Thanks for watching and your interest in this switched capacitor amplifier example. Dividing a signal is not a good practice in general due to noise issues. Also, beyond this example, there are circuit/filter design cases in which 100+ kOhm or Mega Ohm resistors are needed on-chip and those can mainly be realized using switched capacitor techniques. For more circuits please see: Instrumentation Amplifier with Electronic Gain Control kzbin.info/www/bejne/eWXXmJuQYtZpkNU Differential Amplifier Design with BJT transistors kzbin.info/www/bejne/sHzKhIysoJx9d68 Power Amplifier Design (Class A) with Transformer kzbin.info/www/bejne/nXzPe6WnfNaYeas Op Amp Analog Computer Differential Equation Solver kzbin.info/www/bejne/e3_UZGx7mtiZhtk Thermometer Circuit Design with Op Amp & BJT transistor kzbin.info/www/bejne/a2a8pKWXe6pjqMk Push-Pull Power Amplifier with Darlington Transistors kzbin.info/www/bejne/bmeZfoyfl9Rrr6c Analog Logarithm Computer kzbin.info/www/bejne/iKGudqRrjN6igsk Sawtooth Oscillator Design kzbin.info/www/bejne/aJa4pHqGm9aVjZY Triangle Oscillator Op Amp circuit kzbin.info/www/bejne/gHeYhqOVmNp_b80 I hope these Circuit Analysis videos are interesting as well 🙂

[@AnotherPointOfView944]

talking too fast

[@STEMprof]

Thanks for watching & feedback. I'll post more switched capacitor examples. For more circuits please see Op Amp Analog Computer Differential Equation Solver kzbin.info/www/bejne/e3_UZGx7mtiZhtk Instrumentation Amplifier with Electronic Gain Control kzbin.info/www/bejne/eWXXmJuQYtZpkNU Thermometer Circuit Design with Op Amp & BJT transistor kzbin.info/www/bejne/a2a8pKWXe6pjqMk Push-Pull Power Amplifier with Darlington Transistors kzbin.info/www/bejne/bmeZfoyfl9Rrr6c Analog Logarithm Computer kzbin.info/www/bejne/iKGudqRrjN6igsk Sawtooth Oscillator Design kzbin.info/www/bejne/aJa4pHqGm9aVjZY Triangle Oscillator Op Amp circuit kzbin.info/www/bejne/gHeYhqOVmNp_b80 I hope these Circuit Analysis videos are helpful. 🙂

[@davidlavasani8637]

Are you persian? 🤔

[@STEMprof]

Thanks David for watching & your interest. For more Analog circuits please see: Op Amp Analog Computer Differential Equation Solver kzbin.info/www/bejne/e3_UZGx7mtiZhtk Instrumentation Amplifier with Electronic Gain Control kzbin.info/www/bejne/eWXXmJuQYtZpkNU Thermometer Circuit Design with Op Amp & BJT transistor kzbin.info/www/bejne/a2a8pKWXe6pjqMk Push-Pull Power Amplifier with Darlington Transistors kzbin.info/www/bejne/bmeZfoyfl9Rrr6c Analog Logarithm Computer kzbin.info/www/bejne/iKGudqRrjN6igsk Sawtooth Oscillator Design kzbin.info/www/bejne/aJa4pHqGm9aVjZY Triangle Oscillator Op Amp circuit kzbin.info/www/bejne/gHeYhqOVmNp_b80 I hope these Circuit videos are interesting 🙋‍♂️