Your design job, must you resolve to simply accept it: given an enter voltage, sq. it. Okay, that’s too onerous since squaring 8 volts would provide you with 64 volts, so let’s say the output ought to be 10% of the sq., so 8 volts in would end in 6.4V. How do you do it? [Engineering Prof.] is aware of how and can present you what you are able to do within the video under.
The circuit makes use of two op amps and a few transistors. Nevertheless, the transistors are utilized in a approach that relies on the temperature, so it is very important use a transistor array so they’re matched and can all be on the identical temperature.
The mathematics relies on the truth that the transistor response has a pure log time period in it, and the property that the sum of two logs is similar because the log of the product of the numbers.
Due to the matching transistors, lots of the phrases within the equation cancel out. As a result of the transistors are present gadgets, the transistor circuit’s output present is the enter present squared divided by the output transistor’s collector present. Then it’s only a matter of changing the voltage to a present and again once more utilizing the proper scaling.
There’s extra to it, after all, however that’s the gist of it. You’ll be able to dig into the mathematics by watching the video. If the KCL references are fuzzy for you, right here’s a refresher. Squaring a voltage could be fairly vital for an analog laptop.
