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I am aware the max continuous power for a breadboard is 5 Watts. I am creating an amplifier circuit for a 1.7 MHz square wave using a mosfet. I would like to test it using a breadboard before I go further. Power

This is the power dissipated by the resistor that limits the current through drain pin of the mosfet. As you can see the power peak to peak is almost 6 Watts. Would this be okay to test out using a breadboard? I have the spice diagram attached here too. Circuit Diagram

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    \$\begingroup\$ Who says there's a power limit to breadboarding? I've certainly ran more, myself. More important is, will your components' ratings be respected, and can you get the loop inductance low enough for it to behave at this frequency? \$\endgroup\$
    – Tim Williams
    Sep 25 at 20:50
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    \$\begingroup\$ A breadboard is not going to give you high quality results if you are trying to work with a square wave with a fundamental frequency of 1.7 MHz; parasitics are way too high. \$\endgroup\$
    – vir
    Sep 25 at 20:50
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    \$\begingroup\$ Why do you think that the max continuous power for a breadboard is 5 W? Is there a specific breadboard you are talking about? A "breadboard" can mean many things. \$\endgroup\$
    – John D
    Sep 25 at 20:50
  • \$\begingroup\$ The circuit dissipates almost 6 watts peak but it dissipates it 50% of the time and 0W for the other 50% of the time. Therefore your average is max 3 watts. Maybe a bit more since the waveform is not symmetric. \$\endgroup\$
    – Justme
    Sep 25 at 20:54
  • \$\begingroup\$ Please clarify which 'breadboard' by clicking the edit link below the question and adding this information please. Solderless breadboards are a different animal than 'protoboard", 'stripboard', etc. \$\endgroup\$
    – rdtsc
    Sep 25 at 21:20

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I'll assume breadboard = Super-Strip, or equivalent as shown below. image credit: qrk

First off, you are better off using a perfboard for the 1.7 MHz square wave frequency you intend to use which has significant frequency components in to the tens-of-MHz. The switching speed of a FET is such that breadboards don't do well. Copper tape can be used to create low impedance planes for your power connections on a perfboard.

Image of perfboard project showing top & bottom of board. Large copper tape area is ground. Image credit: qrk

Addressing your other concerns about power limitations on a breadboard (perhaps you want to test your circuit at a much lower frequency), power is a hard to quantify parameter on a breadboard. You are most interested in how hot the components will get which is directly relatable to power dissipation of the component, not the breadboard. If the resistor leads get too hot, it will melt the breadboard plastic. If you make the leads longer, the temperature of the leads at the breadboard will be less, however, the inductance of the leads will increase which could cause bad ringing and possibly do something bad.

The other concern is how much current the contact strips on the breadboard can handle. The contact strips will heat up when current is passed through them, how much I do not know.
Cheap breadboards often have high contact resistance which can cause additional heating of the contacts.

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