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Any other suggestions for common yet generally unknown chips?
LM358 op-amp?
Another one - the 33063/34063 type low-voltage DC/DC switchers. Like the TL431, hobbyists almost never use them but they're all over the place.
This was really interesting, but also it just as a byproduct of the explanation actually explains how the core circuit elements are actually implemented (resistors, NPN vs. PNP transistors) which I found really interesting. I had a general idea of transistor implementation, but always just assumed resistors were varying dopants or some such, rather than the now obvious "make it longer/thinner".
But, yeah, if precision and stability do not matter, it's cheaper to make them out of silicon.
Any other suggestions for common yet generally unknown chips?
Earlier quoted context omitted.
LM358 op-amp?
Yeah. That and the LM393/LM339 type comparator-not exactly unknown though. But if I see those used appropriately in a circuit, it's the opposite effect of seeing 741 op-amps and 555 timers and TIP120 transistors. Another one - the 33063/34063 type low-voltage DC/DC switchers. Like the TL431, hobbyists almost never use them but they're all over the place.
Not the cheapest though, about $7 each in qt1 on DigiKey, but that's rarely an issue at the hobby scale. And the ability to use a cheaper transformer and not need an optoisolator can make it save BOM cost even at large scale production.
[1] https://www.analog.com/media/en/technical-documentation/data...
This was really interesting, but also it just as a byproduct of the explanation actually explains how the core circuit elements are actually implemented (resistors, NPN vs. PNP transistors) which I found really interesting. I had a general idea of transistor implementation, but always just assumed resistors were varying dopants or some such, rather than the now obvious "make it longer/thinner".
As a rule, you want your resistors made of metal. Semiconductor resistors have a lot of really surprising behavior. But, yeah, if precision and stability do not matter, it's cheaper to make them out of silicon.
So much so that probably the most common semiconductor resistors where linearity is needed are actually transistors. Stick on external reference resistor in, use current mirrors inside to distribute the reference current around the circuit, and use transistors in the active region (linear region for FETs). It's also cheaper since transistors take less area than resistors.
Earlier quoted context omitted.
The general rule for precision electronics is that you want to avoid anything that needs high absolute accuracy (because such things get expensive fast even as discrete components) and instead rely on accurate ratios between parameters, matched pairs of components and inaccurate, but long term stable parameters that can be calibrated out.
> The general rule for precision electronics is that you want to avoid anything that needs high absolute accuracy (because such things get expensive fast even as discrete components) and instead rely on accurate ratios between parameters, matched pairs of components and inaccurate, but long term stable parameters that can be calibrated out. The omitted serial comma made that really hard to parse for me. In case it di…
> accurate ratios between parameters, and matched pairs of components, and inaccurate - but long-term stable - parameters that can be calibrated out.
is much easier to follow at a glance.
Any other suggestions for common yet generally unknown chips?
The NE555-timer is quite a cool little thing. More common operational amplifiers are also worth looking into (TL072 is one of my favorites). Lastly, the 7400-series logic chips are SO interesting. If you need the programmer's version of a jigsaw puzzle, try to build somewhat advanced designs using those. It's very fun and a good learning experience (although hard!). This guy is building a computer on a breadboard – v…
Earlier quoted context omitted.
> The general rule for precision electronics is that you want to avoid anything that needs high absolute accuracy (because such things get expensive fast even as discrete components) and instead rely on accurate ratios between parameters, matched pairs of components and inaccurate, but long term stable parameters that can be calibrated out. The omitted serial comma made that really hard to parse for me. In case it di…
I've started using hyphens to offset clauses that nest inside of other comma-separated syntactic structures for this reason. It keeps my intent way more clear without forcing the reader to reparse the sentence if they incorrectly guess how the commas are supposed to line up. > accurate ratios between parameters, and matched pairs of components, and inaccurate - but long-term stable - parameters that can be calibrated…
The word minicomputers is a dead link to https://web.archive.org/web/20170118103738/http://bitsavers...., which is some reference documentation for the HP 1000 A600 computer.