HX711 Standalone about hx711

[electrokean]

Don't know if you're still working on this, but essentially your offset is 5219 and your scale is somewhere in the range of -107 to -114.
You also shouldn't be connecting the input outside the specified full scale differential input range, typically +/-20mV or +/-40V (5V supply and gain of 128 or 64).
Also you can't connect a negative voltage at all, or you'll damage the chip. The input is intended to be +/-40mV offset from AVDD/2. This might be why your readings are changing so little over the 0-40mV range you tested with.

[killerkitties]

hi everyone, i hope u all in good.

I dont know if this subject still monitored, but i've try this, HX711 24'bit ADC, as standalone ADC (not as weight scale driver) and the result is unexpectable for me, HX711 is only linier from 0 to 1.000.000, and above that (1m to 8m), it somelike have new gradient (in graph). is anyone has same result? or im the only one got wrong.

note: i wiring this HX711 with wheatstone bridge configuration as same as in load cell, and measure the different between sig+ and sig-.

[electrokean]

@killerkitties Can you provide a drawing of your wiring? You mention a wheatstone bridge configuration, but if measuring a voltage you need to keep the circuits isolated with respect to ground.

The input of the HX711 is designed to measure +/-20mV or +/-40mV centered at about half the supply voltage (i.e. a bit below 2.5V in typical use). Going very far outside of this range the internal amplifier could easily hit linearity issues.

There is some discussion very similar to what you're doing elsewhere which may help, and at least one mention of non-linearity...
http://electronics.stackexchange.com/questions/246418/hx711-voltage-measurements
https://forum.arduino.cc/index.php?topic=413099.0

[bogde]

since there wasn't any feedback on this, i'm closing the issue. feel free to open it again if needed.