Timeline for Linear to log opamp transisor setup
Current License: CC BY-SA 4.0
4 events
| when toggle format | what | by | license | comment | |
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| Nov 3 at 4:13 | comment | added | WhatRoughBeast | @jp314 - And the exponential dependence on temperature gives some insight into why monolithic differential amps, where two transistors are physically adjacent on a chip, has had a very large impact on analog circuit design. Adjacent transistors on a chip are far better matched, both thermally and in terma of gain, than is possible for discrete parts. | |
| Nov 3 at 1:58 | comment | added | jp314 | It's fundamental to the operation of BJTs (at room temperature). The collector current is ISexp(qVBE/kT - 1). kT/q is 26 mV at room temperature. IS will vary device to device, but the rest of the equation is fairly inviolable. | |
| Nov 2 at 22:40 | comment | added | user3810130 | Where does VIN/26mV come from? Is that number based on the numbers I supplied or is it a given 'fact' because I use transistors and thats just part of their behaviour? | |
| Nov 2 at 17:30 | history | answered | jp314 | CC BY-SA 4.0 |