Schematics don’t do you much good on today’s high-tech electronics. Most high-tech electronics nowadays use custom chips or FPGAs so a schematic that shows all the signals going in and out of a magic proprietary chip won’t do you any good.
A lot of lower-tech components that perhaps use discrete parts, relevos, discrete resistors, etc.. do have schematics on the inside of the case or available online.
Lee mas: Diseño de PCB
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