By 2005, I had discovered the translinear, or current-mode thinking in BJT circuit design. Notionally, intended for integrated circuit design, where all the transistors on a single die could have controlled matching properties by virtue of mass fabrication. And similarly, integrated circuit implementation offers concessions in thermal control. Still — its possible to build translinear circuits that work rather well using discrete transistors that are not particularly matched. Given that matching is not specifically guaranteed, it seemed to be prudent to use devices that have high β at low Ic levels. This acted to reduce the base current contribution to errors. So, I used my usual 2N5088 “miracle transistor” for this task.
To test out translinear ideas, the following single-ended to differential convertor was tested. The current to voltage readout op amp for these tests was a LM741. The circuit not only worked marvelously, and was stable, it also essentially embedded multiplication and division. So, a technique ripe for exploitation in other applications.
To test out translinear ideas, the following single-ended to differential convertor was tested. The current to voltage readout op amp for these tests was a LM741. The circuit not only worked marvelously, and was stable, it also essentially embedded multiplication and division. So, a technique ripe for exploitation in other applications.
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