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ESR Meter Adapter Design and Construction

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Jay_Diddy_B:

--- Quote from: Bror Ek on March 30, 2023, 09:12:42 am ---
Snip ...

I put the osc-part demo schematics and info.txt here:
https://groups.io/g/LTspice/files/Temp/Hysteres%2020_70%25%20Virtual%20External%20Input%20Port%20Buffer+Test-Demos.zip

Snip ...


/Bror Ek

--- End quote ---

Bror,

Please attach a screenshot of the schematic modification and attach the .asc file to your post. I can't see the schematic on the groups.io website without signing up.

If your simulation uses models that are not included in the standard LTspice installation, please create a zipfile with everything that is required.

Thanks!!

Jay_Diddy_B

Bror Ek:
Jay,
Hope this helps -

(The RC   'C' should perhaps be increased a few times as long as
a smaller  'R'  won't load to much)

/Bror

Jay_Diddy_B:
Bror,

I checked the Nexperia and the TI datasheets for the 74HCT4053. I do not see any hysteresis on the inputs. If there is no hysteresis this oscillator will not work reliably.

Jay_Diddy_B

Bror Ek:
Yes Jaj, I can not see any specific Schmitt spec,
though in this application the signal edges are distinct and
the switch families gap point levels are well separated,
so in practice there should not be any problem -
see some chip spec. examples further below.

I have no sample in stock to verify yet as the only local over the desk
professional supplier for 2M people closed and I will only mail-order
for some min. items collection.

But I plan to build your design in any working version later as this
is what every household needs  :-+


MC74LVXT4053-
Minimum High−Level Input Voltage, Channel−Select or Enable Inputs: 2.0v (stable at all temperatures)
Maximum Low−Level Input Voltage, Channel−Select or Enable Inputs:  0.8v (stable at all temperatures)
Results in a switch gap of min. 1.2v


TI CD74HC(T)4053 - at Vcc 5v
Min. High-level control input voltage: ~ 3.5V
Max.  Low-level control input voltage: ~ 1.5V
Results in a switch gap of min.  2.0v
(the simulation is closest to this family)

TI New version spec release 03 Mar 2023, TMUX4053 single supply (5 V to 24 V) or
dual supplies (up to ±12 V), or asymmetric supplies.
Min. High-level control input voltage:  1.35V
Max.  Low-level control input voltage:  0.8 V
Results in a switch gap of min.         0.55v
(this might result in close to 4 times higher frequency for the same RC?)
- This chip is also very fast.

/Bror

hbozyq:
After all these years, which version is the "final" version? I still have interest in build one. :)

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