Author Topic: Are there any "up to date" comparators allowing user-selectable hysteresis?  (Read 1119 times)

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Offline 741Topic starter

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Nowadays we have a huge choice of op-amps, which are still used in the same way as older types.

I notice many comparators these days have some small fixed (and sometimes un-specified) hysteresis. This is useful in some instances. Looking at LT's swathe of offerings, it seems most are this type in fact (?)

What are typical part numbers for those comparators allowing traditional "user-defined feedback" from output to a divider at the '+' input? Is it still basically the old LM393? Are there now CMOS versions, maybe even some with open-drain etc?
« Last Edit: July 18, 2019, 08:22:23 am by 741 »
 

Offline 741Topic starter

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Had a look a Microchip and Texas.

For reasons unknown, R2R output implies internal hysteresis  :-//.

I'd really like R2RIO, user-settable hysteresis.

The application would benefit from wide input common-mode range. Having R2R output makes hysteresis feedback design more satisfactory because the design is symmetrical and I can regard a low output as placing feedback resistor "RF" in parallel with lower divider resistor, and a high as placing RF in parallel with the upper divider resistor.

Online tautech

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Application ?
Required package ?
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Offline magic

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What are typical part numbers for those comparators allowing traditional "user-defined feedback" from output to a divider at the '+' input?
Of course you can do it even if there is internal hysteresis, although you cannot disable internal hysteresis if it's present.

For reasons unknown, R2R output implies internal hysteresis  :-//.
Perhaps a measure against output stage crossconduction if you do something stupid like apply negative feedback to continuously keep the output at 50% / oscillating around 50%.
 

Offline Marco

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LTC6752? You pay for it though.
 

Offline scuzzyTerminator

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Might these work for you?

Rail-to-Rail, Very Fast, 2.5 V to 5.5 V,
Single-Supply TTL/CMOS Comparators
ADCMP600/ADCMP601/ADCMP602
(Single-pin control for programmable hysteresis and latch)

https://www.analog.com/media/en/technical-documentation/data-sheets/ADCMP600_601_602.pdf
 


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