Has anyone looked at the ADA4522 precision op amp from Analog Devices. It looks very intriguing with it's extremely low offset voltage drift of 22 nV/°C maximum. The offset voltage is as high as 5 uV but this could be nulled out and it should be very stable over temperature after that. It could be a great choice for a voltage reference circuit. Looks quite inexpensive also, although AD only sell in tubes of 96 right now.

Ada4522-2 and 4522-4 are stocked at mouser. What about summing all outputs to reduce noise? Or use as buffered outputs with good reverse isolation... Daniel Em 07/04/2016 13:31, "Randy Evans" <randyevans2688@gmail.com> escreveu: > Has anyone looked at the ADA4522 precision op amp from Analog Devices. It > looks very intriguing with it's extremely low offset voltage drift of 22 > nV/°C maximum. The offset voltage is as high as 5 uV but this could be > nulled out and it should be very stable over temperature after that. It > could be a great choice for a voltage reference circuit. Looks quite > inexpensive also, although AD only sell in tubes of 96 right now. > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. >

Sure, all good applications. I am thinking of using it as an output filter for a 10V reference to filter all noise above 10Hz, On Thu, Apr 7, 2016 at 6:27 PM, Daniel Mendes <dmendesf@gmail.com> wrote: > Ada4522-2 and 4522-4 are stocked at mouser. What about summing all outputs > to reduce noise? Or use as buffered outputs with good reverse isolation... > > Daniel > Em 07/04/2016 13:31, "Randy Evans" <randyevans2688@gmail.com> escreveu: > > > Has anyone looked at the ADA4522 precision op amp from Analog Devices. > It > > looks very intriguing with it's extremely low offset voltage drift of 22 > > nV/°C maximum. The offset voltage is as high as 5 uV but this could be > > nulled out and it should be very stable over temperature after that. It > > could be a great choice for a voltage reference circuit. Looks quite > > inexpensive also, although AD only sell in tubes of 96 right now. > > _______________________________________________ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > and follow the instructions there. > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. >

Low frequency noise is very good, but is is high noise at about 800kHz (chopper) and above (possible artifacts). That should be filtered, depending on your application. What did you foresee to get rid of it, or would you accept it? Simple RC filter as indicated in the manual increases the output resistance. > Gesendet: Freitag, 08. April 2016 um 03:35 Uhr > Von: "Randy Evans" <randyevans2688@gmail.com> > An: "Discussion of precise voltage measurement" <volt-nuts@febo.com> > Betreff: Re: [volt-nuts] ADA4522 > > Sure, all good applications. I am thinking of using it as an output filter > for a 10V reference to filter all noise above 10Hz, > > On Thu, Apr 7, 2016 at 6:27 PM, Daniel Mendes <dmendesf@gmail.com> wrote: > > > Ada4522-2 and 4522-4 are stocked at mouser. What about summing all outputs > > to reduce noise? Or use as buffered outputs with good reverse isolation... > > > > Daniel > > Em 07/04/2016 13:31, "Randy Evans" <randyevans2688@gmail.com> escreveu: > > > > > Has anyone looked at the ADA4522 precision op amp from Analog Devices. > > It > > > looks very intriguing with it's extremely low offset voltage drift of 22 > > > nV/°C maximum. The offset voltage is as high as 5 uV but this could be > > > nulled out and it should be very stable over temperature after that. It > > > could be a great choice for a voltage reference circuit. Looks quite > > > inexpensive also, although AD only sell in tubes of 96 right now. > > > _______________________________________________ > > > volt-nuts mailing list -- volt-nuts@febo.com > > > To unsubscribe, go to > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > and follow the instructions there. > > > > > _______________________________________________ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > and follow the instructions there. > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. >

I would use a filter such as TI's SBVA010 app note, "Improved Voltage reference Filter has Several Advanatages" or the article by Walt Jung, "Build an Ultra-Low Noise Voltage Reference" in Electronic Design. On Fri, Apr 8, 2016 at 1:02 AM, <acbern@gmx.de> wrote: > Low frequency noise is very good, but is is high noise at about 800kHz > (chopper) and above (possible artifacts). That should be filtered, > depending on your application. > What did you foresee to get rid of it, or would you accept it? Simple RC > filter as indicated in the manual increases the output resistance. > > > > > > Gesendet: Freitag, 08. April 2016 um 03:35 Uhr > > Von: "Randy Evans" <randyevans2688@gmail.com> > > An: "Discussion of precise voltage measurement" <volt-nuts@febo.com> > > Betreff: Re: [volt-nuts] ADA4522 > > > > Sure, all good applications. I am thinking of using it as an output > filter > > for a 10V reference to filter all noise above 10Hz, > > > > On Thu, Apr 7, 2016 at 6:27 PM, Daniel Mendes <dmendesf@gmail.com> > wrote: > > > > > Ada4522-2 and 4522-4 are stocked at mouser. What about summing all > outputs > > > to reduce noise? Or use as buffered outputs with good reverse > isolation... > > > > > > Daniel > > > Em 07/04/2016 13:31, "Randy Evans" <randyevans2688@gmail.com> > escreveu: > > > > > > > Has anyone looked at the ADA4522 precision op amp from Analog > Devices. > > > It > > > > looks very intriguing with it's extremely low offset voltage drift > of 22 > > > > nV/°C maximum. The offset voltage is as high as 5 uV but this could > be > > > > nulled out and it should be very stable over temperature after > that. It > > > > could be a great choice for a voltage reference circuit. Looks quite > > > > inexpensive also, although AD only sell in tubes of 96 right now. > > > > _______________________________________________ > > > > volt-nuts mailing list -- volt-nuts@febo.com > > > > To unsubscribe, go to > > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > > and follow the instructions there. > > > > > > > _______________________________________________ > > > volt-nuts mailing list -- volt-nuts@febo.com > > > To unsubscribe, go to > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > and follow the instructions there. > > > > > _______________________________________________ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > and follow the instructions there. > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. >

not sure the TI filter circuitry, although very nice, is stable with the ADA4522. have not checked, but R2/C2 loop stabilizer may not work with ad4522. would require analysis/test, but positive result would sure make this a great reference buffer amp. if you do, would be nice if you let the group know. > Gesendet: Samstag, 09. April 2016 um 00:38 Uhr > Von: "Randy Evans" <randyevans2688@gmail.com> > An: "Discussion of precise voltage measurement" <volt-nuts@febo.com> > Betreff: Re: [volt-nuts] ADA4522 > > I would use a filter such as TI's SBVA010 app note, "Improved Voltage > reference Filter has Several Advanatages" or the article by Walt Jung, > "Build an Ultra-Low Noise Voltage Reference" in Electronic Design. > > On Fri, Apr 8, 2016 at 1:02 AM, <acbern@gmx.de> wrote: > > > Low frequency noise is very good, but is is high noise at about 800kHz > > (chopper) and above (possible artifacts). That should be filtered, > > depending on your application. > > What did you foresee to get rid of it, or would you accept it? Simple RC > > filter as indicated in the manual increases the output resistance. > > > > > > > > > > > Gesendet: Freitag, 08. April 2016 um 03:35 Uhr > > > Von: "Randy Evans" <randyevans2688@gmail.com> > > > An: "Discussion of precise voltage measurement" <volt-nuts@febo.com> > > > Betreff: Re: [volt-nuts] ADA4522 > > > > > > Sure, all good applications. I am thinking of using it as an output > > filter > > > for a 10V reference to filter all noise above 10Hz, > > > > > > On Thu, Apr 7, 2016 at 6:27 PM, Daniel Mendes <dmendesf@gmail.com> > > wrote: > > > > > > > Ada4522-2 and 4522-4 are stocked at mouser. What about summing all > > outputs > > > > to reduce noise? Or use as buffered outputs with good reverse > > isolation... > > > > > > > > Daniel > > > > Em 07/04/2016 13:31, "Randy Evans" <randyevans2688@gmail.com> > > escreveu: > > > > > > > > > Has anyone looked at the ADA4522 precision op amp from Analog > > Devices. > > > > It > > > > > looks very intriguing with it's extremely low offset voltage drift > > of 22 > > > > > nV/°C maximum. The offset voltage is as high as 5 uV but this could > > be > > > > > nulled out and it should be very stable over temperature after > > that. It > > > > > could be a great choice for a voltage reference circuit. Looks quite > > > > > inexpensive also, although AD only sell in tubes of 96 right now. > > > > > _______________________________________________ > > > > > volt-nuts mailing list -- volt-nuts@febo.com > > > > > To unsubscribe, go to > > > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > > > and follow the instructions there. > > > > > > > > > _______________________________________________ > > > > volt-nuts mailing list -- volt-nuts@febo.com > > > > To unsubscribe, go to > > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > > and follow the instructions there. > > > > > > > _______________________________________________ > > > volt-nuts mailing list -- volt-nuts@febo.com > > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > and follow the instructions there. > > > > > _______________________________________________ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > and follow the instructions there. > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. >

Why?The ADA4522 is unity gain stable with about 60 degrees of phase margin.The equivalent output inductance at unity gain is about 0.5u 50 ohms in series with the 1uF output capacitance ensures an overdamped response. Bruce On Saturday, 9 April 2016 11:20 PM, "acbern@gmx.de" <acbern@gmx.de> wrote: not sure the TI filter circuitry, although very nice, is stable with the ADA4522. have not checked, but R2/C2 loop stabilizer may not work with ad4522. would require analysis/test, but positive result would sure make this a great reference buffer amp. if you do, would be nice if you let the group know. > Gesendet: Samstag, 09. April 2016 um 00:38 Uhr > Von: "Randy Evans" <randyevans2688@gmail.com> > An: "Discussion of precise voltage measurement" <volt-nuts@febo.com> > Betreff: Re: [volt-nuts] ADA4522 > > I would use a filter such as TI's SBVA010 app note, "Improved Voltage > reference Filter has Several Advanatages" or the article by Walt Jung, > "Build an Ultra-Low Noise Voltage Reference" in Electronic Design. > > On Fri, Apr 8, 2016 at 1:02 AM, <acbern@gmx.de> wrote: > > > Low frequency noise is very good, but is is high noise at about 800kHz > > (chopper) and above (possible artifacts). That should be filtered, > > depending on your application. > > What did you foresee to get rid of it, or would you accept it? Simple RC > > filter as indicated in the manual increases the output resistance. > > > > > > > > > > > Gesendet: Freitag, 08. April 2016 um 03:35 Uhr > > > Von: "Randy Evans" <randyevans2688@gmail.com> > > > An: "Discussion of precise voltage measurement" <volt-nuts@febo.com> > > > Betreff: Re: [volt-nuts] ADA4522 > > > > > > Sure, all good applications.  I am thinking of using it as an output > > filter > > > for a 10V reference to filter all noise above 10Hz, > > > > > > On Thu, Apr 7, 2016 at 6:27 PM, Daniel Mendes <dmendesf@gmail.com> > > wrote: > > > > > > > Ada4522-2 and 4522-4 are stocked at mouser. What about summing all > > outputs > > > > to reduce noise? Or use as buffered outputs with good reverse > > isolation... > > > > > > > > Daniel > > > > Em 07/04/2016 13:31, "Randy Evans" <randyevans2688@gmail.com> > > escreveu: > > > > > > > > > Has anyone looked at the ADA4522 precision op amp from Analog > > Devices. > > > > It > > > > > looks very intriguing with it's extremely low offset voltage drift > > of 22 > > > > > nV/°C maximum.  The offset voltage is as high as 5 uV but this could > > be > > > > > nulled out and it should be very stable over temperature after > > that.  It > > > > > could be a great choice for a voltage reference circuit.  Looks quite > > > > > inexpensive also, although AD only sell in tubes of 96 right now. > > > > > _______________________________________________ > > > > > volt-nuts mailing list -- volt-nuts@febo.com > > > > > To unsubscribe, go to > > > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > > > and follow the instructions there. > > > > > > > > > _______________________________________________ > > > > volt-nuts mailing list -- volt-nuts@febo.com > > > > To unsubscribe, go to > > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > > and follow the instructions there. > > > > > > > _______________________________________________ > > > volt-nuts mailing list -- volt-nuts@febo.com > > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > and follow the instructions there. > > > > > _______________________________________________ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > and follow the instructions there. > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. > _______________________________________________ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.