What replaces an LM358, LM324, LM741, LM311, LM393 or TL071?

The substitutes, and what each one actually is

A drop-in here means the same package, the same pin map and the same function — a dual op-amp for a dual op-amp. Function count is the first thing to check, because that is where the socket stops telling you the truth.

The same socket, four different parts

The DIP-8 outline is shared by a single op-amp, a dual op-amp and two flavours of comparator, and the pin map is only consistent within one family. The three that catch people are worth naming: the LM311 against the LM393, where pin 1 changes meaning from a ground reference to an output; the LM339 against the LM324, a quad comparator against a quad op-amp in an identical 14-pin body; and the TL071 against the TL072, a single against a dual, where the dual loses the offset-null pins entirely and puts the second channel on pins 5 to 7.

A comparator is not a slow op-amp and an op-amp is not a comparator with hysteresis missing. Both fit the same footprint in several of these rows — the LM393 and the LM358 are both 8-pin — and the difference shows up as behaviour rather than as a failure to fit: an op-amp used as a comparator is usually too slow and may not tolerate the differential input it sees, and a comparator used as an amplifier has no phase compensation for the feedback you are about to wrap around it.

Null pins, grades and the quiet differences

The offset-null pins are the other quiet divider. The LM741, the TL071 and the uA741 carry null on pins 1 and 5; the LM358 and the LM324 do not have them at all, and the LM833 is described in the same breath as a standard dual pinout with no null pins. When a board uses those pins, the substitute has to provide them — and when it does not, a part that has them is harmless, which is why the rolling slot in audio gear tolerates the NE5532 / OPA2134 direction so well.

Grades and temperature windows are the third axis, and they are where the letters live. LM324, LM2902, LM324B and LM324LV are the same quad op-amp across different grade and supply families; LM311, LM211 and LM111 are the same comparator across temperature windows. Moving between them changes the specification you were relying on, not the part you are replacing.

What we will not claim

Every mapping above was checked against the manufacturer datasheet for package, pin map and function count, and where the datasheet did not support one it is not listed. Three rows carry do not insert rather than a substitute, because that is what the data supports. Confirm against your own schematic before a redesign, and treat the level as the scope of the risk.