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Class E Power amplifier

I am designing a Class E power amplifier for 450MHz frequency. But how to fix the Q factor for the series LC in the output stage of the Power amplifier?...Read more

Power amplifier circuit

In the power amplifier circuit shown if the input is an RF sine wave, with VDD=1.8V and Vgs = 1V, what will be the waveform at the drain of the MOSFET - sine or square wave? Is it possible to get a sine wave at the drain?...Read more

Gain block vs power amplifier

I was searching for some IC to amplify a signal (like a RF frontend before an antenna) to have a stronger RF signal. I come across 2 terms and I don't really understand the difference between them. What is the difference between a gain block and a power amplifier?...Read more

Conventional current in a power amplifier?

I recently learned that electricity doesn't actually flow from + to - but the other way around.. So my question would be: if I was using a 2 channel power amp and connected a speaker to it with the positive wire on the left channel (+) and the negative on the right channel (-) would I get the output of the left channel or the right channel? I thought the (-) terminal on an amp was just to take the signal and ground it....Read more

power amplifier - Circuit Definition

This is a circuit that I've found in my old amplifier board. Experts please help me identify this circuit and please describe how it works. I am sorry for my crude drawing, but this is what I found when drawing it from the circuit board. It was built using smd components so it was a bit difficult for me to find the exact match of the transistors. There might be some mistake in the circuit and it will be helpful if any of you take your time to rectify it for me.The output node was connected to the non-inverting input of the power amplifier along...Read more

Class F amplifier analysis

I can't figure out why drain voltage is rectangular in the following circuit:I tried this:$$V_{ds}=V_{DD}-I_{fund}R_lsin(\omega_0t)-I^{(2)}Z_{in}^{(2)}sin(2\omega_0t)-I^{(3)}Z_{in}^{(3)}sin(3\omega_0t)...$$$$I^{(k)}= \int i_{d}sin(k\omega_0t)dt$$$$Z_{in}^{(2k)}=0\\Z_{in}^{(2k+1)}=\infty\rightarrow I^{(2k+1)}=0$$$$\rightarrow V_{ds}=V_{DD}-R_lI_{fund}sin(\omega_0t)$$So the output I get is sinusoid but the reference I studied states it is rectangular. Would anyone please help me with this?Edit: The transistor is assumed to act as switch....Read more

power amplifier - Amplify Arduino Due DAC output

I need to drive an inductive load from an Arduino Due analog output. The analog output delivers 0.55V-2.75V (yes, it doesn't deliver 0 volts). I need to get something like 0-14V with up to 3A maximum and so that the output voltage is linearly dependent of the input voltage.Now I am overwhelmed by all the possibilities to achieve this. I do not know if I have to use MOSFETS or Operational Amplifiers and so on. I have seen solutions like this but this doesn't get me currents up to 3A? I would like the simplest solution. If I can buy something sma...Read more