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Opamp w/ Vsupply >36V

Started by George Herold July 15, 2013
Opamp Vsupply >36V

Hi all,  I=92ve got a circuit with that uses an opa2134.  I find myself pus=
hing the 36V supply limit and I=92m a little worried.   So I went looking f=
or a similar opamp but with a bit more headroom. =20
So specs might read,

Dual opamp
unity gain stable=20
4(+) Mhz BW (8MHz or more would be nicer)
10 V/us slew (again more is better)
20mA  current (positive, again more would be nicer)
small input C ( <5pF would be nice.)
8 pin dip preferred

Trolling digikey I found a few possible candidates. =20

TLE2142 (6 MHz GBW)
TLE2072 (only 38 V supply, 11 pF input C)
OPA2604 (nice but 10 pF input C)=20
(I=92ll order a few of each.)

There was also the LF412A, but a bit lacking is positive supply current. =
=20

Any others that I might have missed? =20

Thanks,=20
George H.
On Mon, 15 Jul 2013 09:01:21 -0700, George Herold wrote:

> Opamp Vsupply >36V > > Hi all, I&rsquo;ve got a circuit with that uses an opa2134. I find myself > pushing the 36V supply limit and I&rsquo;m a little worried. So I went > looking for a similar opamp but with a bit more headroom. So specs might > read, > > Dual opamp > unity gain stable > 4(+) Mhz BW (8MHz or more would be nicer) 10 V/us slew (again more is > better) > 20mA current (positive, again more would be nicer) small input C ( <5pF > would be nice.) > 8 pin dip preferred > > Trolling digikey I found a few possible candidates. > > TLE2142 (6 MHz GBW) > TLE2072 (only 38 V supply, 11 pF input C) OPA2604 (nice but 10 pF input > C) > (I&rsquo;ll order a few of each.) > > There was also the LF412A, but a bit lacking is positive supply current. > > Any others that I might have missed? > > Thanks, > George H.
TI lists some opamps with varying maximum voltage limits. Try: http://www.ti.com/lsds/ti/amplifiers-linear/high-supply-voltage-amplifier-greater-than-equal-30v-products.page HTH..
On Mon, 15 Jul 2013 09:01:21 -0700 (PDT), George Herold <gherold@teachspin.com>
wrote:

>Opamp Vsupply >36V > >Hi all, I&#2013266066;ve got a circuit with that uses an opa2134. I find myself pushing the 36V supply limit and I&#2013266066;m a little worried. So I went looking for a similar opamp but with a bit more headroom. >So specs might read, > >Dual opamp >unity gain stable >4(+) Mhz BW (8MHz or more would be nicer) >10 V/us slew (again more is better) >20mA current (positive, again more would be nicer) >small input C ( <5pF would be nice.) >8 pin dip preferred > >Trolling digikey I found a few possible candidates. > >TLE2142 (6 MHz GBW) >TLE2072 (only 38 V supply, 11 pF input C) >OPA2604 (nice but 10 pF input C) >(I&#2013266066;ll order a few of each.) > >There was also the LF412A, but a bit lacking is positive supply current. > >Any others that I might have missed? > >Thanks, >George H.
If it's rated 36 max, use it up to 36. The manufacturer has already factored in the headroom. Or, from my stock listing, TLE2142 MC33072 OPA552 OP27 OP37 OP77 LT1001 OP497 TCA0372 beast! -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multichannel arbitrary waveform generators
On Monday, July 15, 2013 12:12:28 PM UTC-4, cassiope wrote:
> On Mon, 15 Jul 2013 09:01:21 -0700, George Herold wrote: > > > > > Opamp Vsupply >36V >
> TI lists some opamps with varying maximum voltage limits. Try: > > http://www.ti.com/lsds/ti/amplifiers-linear/high-supply-voltage-amplifier-greater-than-equal-30v-products.page > > > > HTH..
Thanks, That a bit better than the last time I did a parameter search on TI's site. George H.
On Monday, July 15, 2013 12:52:53 PM UTC-4, John Larkin wrote:
> On Mon, 15 Jul 2013 09:01:21 -0700 (PDT), George Herold <gherold@teachspi=
n.com>
>=20 > wrote: >=20 >=20 >=20 > >Opamp Vsupply >36V >=20 > > >=20
> >TLE2142 (6 MHz GBW) >=20 > >TLE2072 (only 38 V supply, 11 pF input C) >=20 > >OPA2604 (nice but 10 pF input C)=20 >=20 > >(I=92ll order a few of each.) >=20 > > >=20 > >There was also the LF412A, but a bit lacking is positive supply current.=
=20
>=20 > > >=20 > >Any others that I might have missed? =20 >=20 > > >=20 > >Thanks,=20 >=20 > >George H. >=20 >=20 >=20 > If it's rated 36 max, use it up to 36. The manufacturer has already facto=
red in
>=20 > the headroom.
Well I might be using 'headroom' the wrong way. I'm splitting a 48 V wallw= art,=20 ground is a few volts above the bottom rail and then ~35 volts down from th= e top for the positive rail. But 35 volts designed and 1% resistors that's= about a 4% max error... 36.4 volts. I'm feeling squeezed. =20
>=20 >=20 >=20 > Or, from my stock listing, >=20 >=20 >=20 > TLE2142 >=20 >=20 >=20 > MC33072 >=20 >=20 >=20 > OPA552 >=20 >=20 >=20 > OP27 >=20 >=20 >=20 > OP37 >=20 >=20 >=20 > OP77 >=20 >=20 >=20 > LT1001 >=20 >=20 >=20 > OP497 >=20 >=20 >=20 > TCA0372 beast! >=20
Thanks I'll look at those. =20 (I rejected the MC33072 already.) I've got some TCA0372's in stock, but haven't played with them yet. =20 (too slow for this job.) George H.
>=20 > John Larkin Highland Technology Inc >=20 > www.highlandtechnology.com jlarkin at highlandtechnology dot com =20 >=20 >=20 >=20 > Precision electronic instrumentation >=20 > Picosecond-resolution Digital Delay and Pulse generators >=20 > Custom timing and laser controllers >=20 > Photonics and fiberoptic TTL data links >=20 > VME analog, thermocouple, LVDT, synchro, tachometer >=20 > Multichannel arbitrary waveform generators
On Mon, 15 Jul 2013 09:52:53 -0700, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

> >If it's rated 36 max, use it up to 36. The manufacturer has already factored in >the headroom.
Make sure there are no transients possible on the power supplies etc. if you do this. I once had a really horrible experience using 16V TI CMOS op-amps at the system supplies of +/-8V (almost 1% failure rate).
On 7/15/2013 11:12 AM, Spehro Pefhany wrote:
> On Mon, 15 Jul 2013 09:52:53 -0700, John Larkin > <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote: > >> >> If it's rated 36 max, use it up to 36. The manufacturer has already factored in >> the headroom. > > Make sure there are no transients possible on the power supplies etc. > if you do this. I once had a really horrible experience using 16V TI > CMOS op-amps at the system supplies of +/-8V (almost 1% failure rate). >
You can get a lot of soft failures due to overstress, but the part keeps "working." A soft failure in a chip is something like the shutdown current out of spec or the input impedance is low, etc. Often chips have soft failures and nobody notices. For instance, a bit of increased shutdown current can be lost if there are a lot of parts on the board. A lower impedance on an input may not matter if the rest of the components are low impedance. But your problem sheds light on an interesting test problem, namely absmax. There is no standard on how to test parts beyond their datasheet limits. Some companies only QA absmax. They stress the part and see if it still meets spec when used at stated voltages. Others do a real absmax test, but not at strict electrical limits. But then there is the question of should you be stressing your parts at all? But to get 99% failure when operated at the datasheet limits implies to me a part that has other problems rather than your supply being the culprit. There is a lot of margin in absmax. That said, transorb diodes are highly recommended!
On Monday, July 15, 2013 2:12:49 PM UTC-4, Spehro Pefhany wrote:
> On Mon, 15 Jul 2013 09:52:53 -0700, John Larkin >=20 > <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote: >=20 >=20 >=20 > > >=20 > >If it's rated 36 max, use it up to 36. The manufacturer has already fact=
ored in
>=20 > >the headroom. >=20 >=20 >=20 > Make sure there are no transients possible on the power supplies etc. >=20 > if you do this. I once had a really horrible experience using 16V TI >=20 > CMOS op-amps at the system supplies of +/-8V (almost 1% failure rate).
Grin, the first time I did the circuit I had big caps (10uF) from the inpu= t 'grounds'* to the regulated voltages. (LM317/337's) The positive supply w= as fine, but the negative supply would 'turn on' to ~1/2 the supply voltage= . (Caps basically split the supply to start with) and then went down as th= e regulator took over. This took out a voltage reference downstream ~50% = of the time. (Bad cap!) George H. =20 *'ground' for the LM337 was the positive supply input.
On Mon, 15 Jul 2013 14:12:49 -0400, Spehro Pefhany
<speffSNIP@interlogDOTyou.knowwhat> wrote:

>On Mon, 15 Jul 2013 09:52:53 -0700, John Larkin ><jjlarkin@highNOTlandTHIStechnologyPART.com> wrote: > >> >>If it's rated 36 max, use it up to 36. The manufacturer has already factored in >>the headroom. > >Make sure there are no transients possible on the power supplies etc. >if you do this. I once had a really horrible experience using 16V TI >CMOS op-amps at the system supplies of +/-8V (almost 1% failure rate).
Another opamp that you can't push is HFA1130. It's spec'd for 12 volts, and it will die at 12 volts. Older analog processes, like for classic 741 and LF353 types, would fail way past ratings, numbers like 60 volts. Newer parts cut things tighter. Or maybe specmanship has got more intense. -- John Larkin Highland Technology, Inc jlarkin at highlandtechnology dot com http://www.highlandtechnology.com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom laser drivers and controllers Photonics and fiberoptic TTL data links VME thermocouple, LVDT, synchro acquisition and simulation
On Monday, July 15, 2013 12:01:21 PM UTC-4, George Herold wrote:
> Opamp Vsupply >36V >
Fix your power supply and use readily available, and commonly used, OAs.