TL3474: Propagation delay

Some datasheets show the large-signal step response (e.g., below for the TLV9354/OPA4991).

But the TL3474 is rather old, and its datasheet lacks this information. Consider using a more modern opamp, or better a comparator.

(Analog amplifiers react to small changes in their inputs with a small change at the output, so the output starts moving earlier than with a comparator. This and the relatively slow slew rate means that the propagation delay is almost entirely determined by the rise/fall rate.)

Hello Itoh-san,

In your picture, prop delay includes 1/2 of rise and fall times. This is fine for a comparator, but that doesn't work well with an op amp that has naturally slow rise and fall times. Some op amps have an 'overload recovery time' that is same as propagation delay except it doesn't include half of rise time. TL3474 predates having overload recovery as a standard parameter. The Rise and fall times are called slew rate. 

For what reason is this request made?

For more information about slew rate vs overdrive see application note: [APP] Ramping Up on Slew Rate