common source mosfet amplifier

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kavkav

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I'm using IRF610 Mosfet
https://pdf1.alldatasheet.com/datashe...LD/IRF610.html

to build a common source amplifier. The mosfet is n-channel enhancement mode.

I have read everything I could find on mosfets, read my lectures and still I don't understand how to do this. This is the best schematic I could find but I have no idea how to choose my resistor values:

**broken link removed**

I would greatly appreciate if someone could could guide me through this because everything I've come across, uses formulas which require a "gm" value or "k" parameter or "W/L" parameter and non of these which I have. I can't even calculate my gain because it depends on what resistors I use.

SPECS:
Power Supply: 24 Volts DC
Signal Source: 1000Hz AC from function generator with 150 ohm internal resistance (can go from -5 to +5 volts in amplitude)
voltage Gain: voltage of signal should multiply by a factor of 3 (at least).
Current Gain: I don't know as long as power gain is significantly higher than signal source
V(th): 2 to 4 volts according to datasheet

Thanks.
 

Some of your requirements are a little fuzzy ---

What is the maximum voltage you want to amplify?

Do you want maximum voltage gain or just a gain somewhat greater than 3.

What is the output load impedance?

What is the maximum amplifier supply current you can tolerate.
 

My power supply is 24 Volts. My function generator gives a signal and the max voltage amplitude of the signal can be 5 Volts. So if the signal is at a constant 5Volts I want my output to be the same signal but with and amplitude of at least 15 Volts. If the signal Is 2 volts amplitude, I want the amplified version to be at least 15 Volts in amplitude. So I guess I'm saying the amplified signal should end up having at least 15 Volts of amplitude.

I prefer maximum voltage gain. So even if I can get an amplitude of 23 Volts from the 24 volt power supply I will be happy.

The output is going to be a step-up transformer. The wiring itself is 15 ohms. The inductance is 264 uH.

Maximum amplifier supply current I can tolerate is 2.5 Amps from my 24 Volt power supply.

Thank you for your reply.
 

Is this a square-wave or sinusoidal signal?

You can't get the same signal output amplitude with different input amplitudes unless you vary the gain or clip the output. It sounds like you want a maximum output square-wave, independent of the input. Is that the case?
 

The input signal will be a clean square wave. So I want the output to be a amplified version of that.
 
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