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What is your favorite most versatile op-amp?
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David Hess:

--- Quote from: maxwell3e10 on May 06, 2019, 03:26:30 am ---These are not the requirements for one specific design, more like an amalgam of reasonable requirements one can expect to get across the board- a versatile chip one can pop in many circuits.
--- End quote ---

The simultaneous precision and output current requirements conflict to make one or the other unreasonable. 

The supply voltage and output current requirements also conflict with the DIP-8 packaging requirement; parts with that kind of output current are limited to lower supply voltage, typically about +/- 8 volts.  (1) The datasheet for the LT1010 power buffer has a good discussion about the power limitations of the DIP-8 package.  Another place to find discussion of this issue is in the datasheets for +/-15 volt current feedback amplifiers.

The LT1010 works well as the output stage of a composite amplifier but even it would not meet your output power requirements without help unless used in the TO-220 package and perhaps not even then.  There are some current feedback amplifiers with 50 milliamp output current but they have the same problem.

(1) This comes up when driving a double terminated 50 ohm transmission line which presents a 100 ohm load.  +/-5 volts into 100 ohms is +/-50 milliamps.  Adding another 3 volts for headroom results in the +/-8 volt supply requirement.
OM222O:
David Hess is right, that was also the first thing that I pointed out  :-DD just using a buffer for the power stage seems like the logical option as OP AMPs aren't really meant to drive any loads.
maxwell3e10:
And yet there are old popular chips, like LM6171 in a PDIP package, and new designs like OPA2156, which have 100mA+  current capability.

Of course there will be power dissipation limitations, but often one doesn't need to drive high current continuously. And maybe literally the same chip can't be used to drive high current and have low voltage offset, but its nice to have a circuit that uses the same type of chip both for the input and output stage.

The basic question is to find an op-amp that can cover as much parameter space volume as possible without sacrificing too much in any other characteristics. 
David Hess:

--- Quote from: maxwell3e10 on May 06, 2019, 02:38:26 pm ---And yet there are old popular chips, like LM6171 in a PDIP package, and new designs like OPA2156, which have 100mA+  current capability.


--- End quote ---

The LM6171 is a current feedback amplifier in disguise with a buffered inverting input.  This is a great topology for high speed but not a precision one.

The OPA2156 is typical of misleading TI datasheets.  The precision specifications only apply with a high impedance load and low power dissipation.  No settling time specifications is given with a high output current because it is 1000s of times worse than the datasheet specification as it would be with any integrated operational amplifier.  So you can use it for high output current or high precision but not both at the same time.  With that high noise, it is not suitable for low frequency precision applications anyway but that is typical of CMOS processes.

The above may seem like nit-picking but consider the lessor known advantage of super-beta input parts like the old 308 and "modern" LT1008/LT1012/LT1097.  Their very low input bias current means that a high impedance feedback network can be used minimizing power dissipation in the output stage yielding better precision.  Lower noise parts like the OP07/LT1001 or OP27/LT1027 require much lower impedance feedback networks to avoid compromising their lower noise but this requires higher power dissipation in their output stage compromising precision.  In this respect, the "universal" part might be the LT6010/LT6011/LT6012 which is a rail-to-rail output version of the LT1012.  Note that no such single supply or rail-to-rail part like this can exist because single supply operation conflicts with input bias current cancellation.  Of course FET inputs do not require input bias current cancellation but they have their own problems.

Also notice that the OPA2156 specifications exclude input capacitance versus common mode voltage and do not mention source impedance in non-inverting applications.  That is deliberate.  In any real circuit, the non-zero source impedance interacts with the variable input capacitance to produce much higher distortion than they show.  There are ways to fix this but I am not sure that they apply to a rail-to-rail input part or standard CMOS process.

The OPA2156 is a great part for general purpose use but I would still prefer it to be available in a single version to take advantage of circuits which require access to the power pins.  That is a requirement I would add for any part to be most versatile.

maxwell3e10:
Many of these precision parts, like LT1012 and LT6012 have terrible slew rates, so while they maybe good for precision DC applications, they are not good for any dynamic application. A good general chip will not be ideal for any application (not lowest noise or highest slew rate or lowest distortion), but will be pretty good for all of them.

What do you think about OPA2189? It seems to have better specs than any other chopper op-amp I have seen?

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