2 ms·
Great writeup! Is there any way to determine the values of the resistors and capacitors on the die based on their geometry, or would someone have to build up a
by MegaDeKay 9y ago
Great writeup!
Is there any way to determine the values of the resistors and capacitors on the die based on their geometry, or would someone have to build up a standalone circuit and experiment until coming up with something that sounded similar? Can a person at least infer one value from another by the ratio of the geometries, like one resistor being 2x another if it were twice as long?
BTW, I built up a perfboard with this chip and a pile of resistors, capacitors, and potentiometers many moons ago. Just tore it down a short while ago. 76477 was also my Automated Teller Machine password for a lot of years.
- kens 9y agoThe resistance is proportional to the length/width ratio as you suspect. You can find resistance numbers for doped silicon, but the value depends on the doping level. So you can get a rough idea. Because resistances can vary 20% from chip to chip, analog circuits generally are designed so the ratio of two resistances controls things, rather than the absolute resistance. So you probably don't need to figure out the absolute resistance.