I would strongly recommend getting a copy of the excellent "Opamps for Everyone", 5th ed. by Bruce Carter & Ron Mancini. It's one of my go-to books...
https://www.amazon.co.uk/Op-Amps-Everyone-Bruce-Carter-dp-012811648X/dp/012811648X This is a highly revised version of the original Rev B version of Texas Instruments' book by Mancini that is available for free from TI's at https://e2echina.ti.com/cfs-file/__key/telligent-evolution-components-attachments/00-52-01-00-00-04-59-46/OP-amp-for-everyone.pdf TI (and others) have great free analogue design guides... for some more of TI's, see https://www.ti.com/amplifier-circuit/op-amps/technical-documents.html HTH Nick On Friday, 2 April 2021 at 16:03:17 UTC+1 Chuck wrote: > Makes perfect sense. Thank you. So far I've used op amps for a few > simple things but still need lots of study and practice to become more > proficient with them. > > To date my experience with op amps has all been cookie-cutter cookbook > applications. They work, but much more study is required. At least I now > know a little more > > about the proper way to tie off the unused ones. Thanks. -Chuck > > > ---- Original Message ---- > From: "gregebert" <[email protected]> > Sent: 4/1/2021 7:36:20 PM > To: "neonixie-l" <[email protected]> > Subject: Re: [neonixie-l] LM-324 op amp > > An op-amp is a high-gain amplifier, so if both inputs are tied to the same > voltage, then noise will amplified thru the op-amp and cause the output to > jump around. As others have said, this can lead to oscillation. Noise is > not just what is present at the inputs; it's also inherent in the op-amp > itself. Even the pullup or pulldown resistors you use are a source of noise. > > By tying the unused output to the inverting input, you have a stable > unity-gain amplifier, thanks to the internal compensation. You can then tie > the non-inverting input to gnd, vcc, or preferably something inbetween. > > > > > On Thursday, April 1, 2021 at 12:21:55 PM UTC-7 jrehwin wrote: > >> > That actually sounds kind of like the old military practice of >> grounding unused TTL inputs through a 1k resistor. >> >> I thought the military practice was to tie unused inputs high (instead of >> grounding them) through a resistor: TTL takes less current to pull high >> than to pull low. >> >> - John >> > > -- > > > You received this message because you are subscribed to the Google Groups > "neonixie-l" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > > To view this discussion on the web, visit > https://groups.google.com/d/msgid/neonixie-l/3ee71a8e-a9ec-4527-8b9b-b81047ddec5fn%40googlegroups.com > > <https://groups.google.com/d/msgid/neonixie-l/3ee71a8e-a9ec-4527-8b9b-b81047ddec5fn%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/eb6ebd9a-9919-4e56-a05c-b7063b2a5e9an%40googlegroups.com.
