Signal delays for synchronous rectifier drive

[cupoftea]

Hi,
Trying to make some gate drive delays for a synchronous rectifier drive. (using typical diode/R/C circuits with logic buffers) Cant use standard logic buffers, since there internal reference has too wide tolerance. Thus have to use comparators, buffers and references.

Is there such thing as a logic buffer with reasonably accurate reference? (+/-0.1V)
(LTspice and jpeg attached)

--- Updated May 25, 2023 ---

This gate driver is said to have thresholds of 1-1.2V for low, and 2.2-2.4v for high....but does that mean "anything below 1v is low"....or is the "1-1.2v" a tightly toleranced threshold?

UCC27517

https://www.ti.com/lit/ds/symlink/ucc27517.pdf?ts=1685004074839&ref_url=https%253A%252F%252Fwww.google.fr%252F

 

[std_match]

This gate driver is said to have thresholds of 1-1.2V for low, and 2.2-2.4v for high....but does that mean "anything below 1v is low"....or is the "1-1.2v" a tightly toleranced threshold?

It means both, When going from high to low, the transition happens somewhere between 1.0 and 1.2V, and it is independent of the supply voltage. When the transition has happened, the hysteresis makes it stay low until the voltage goes above 2.2V - 2.4V

 

[dick_freebird]

If logic threshold matters to delay then your input transition time
is not "logic grade". RC delay add-ons worsen that.

Comparators are much slower and have their own delay variability
(and esp. at low overdrive, again posing problems for consistency of
timing when slow dV/dt).

 

[cupoftea]

Thanks, though would you agree, that as long as overdrive is 100mV, then this MCP6566 comparator will switch within 80ns?

https://ww1.microchip.com/downloads/en/DeviceDoc/MCP6566-6R-6U-7-9-1.8V-Low-Power-Open-Drain-Output-Comparator-DS20002143G.pdf

..I mean, we could always upgrade to the LT1713, but our timing is not needing of great accuracy, just as long as we can avoid shoot-through...we can always have bigger dead time so our timing can be a little looser....but the cheap 1us comparators are out of the question, as you kindly suggest...eg LM393 and co, are no-goers for us.

LT1713

https://www.analog.com/media/en/technical-documentation/data-sheets/171314f.pdf

..Am still wondering about using the UCC27517 (from the top post) as a "comparator with reference here"
UCC27517

https://www.ti.com/lit/ds/symlink/ucc27517.pdf?ts=1685004074839&ref_url=https%253A%252F%252Fwww.google.fr%252F

Its pretty amazing if you cant do yourself a ~100-500ns delay in hardware....with any components available offTheShelf.

The shown LTspice sim has delays with reference voltages differing by 200mV...but the delay each provides is pretty much the same....or near enough for our purposes.