baileychic
Advanced Member level 3
I am making a HX711 based Weighing Scale using PIC16F877A.
The datasheet
https://cdn.sparkfun.com/datasheets/Sensors/ForceFlex/hx711_english.pdf
mentions that for input channel A that is A+ and A then gain can be 64 or 128 and if 128 is chosen as gain then differential input can be +/40mV.
Does it mean that input can be 40mV to +40mV = 80 mV range?
80 mV = 2^24 = 0 to 16777215?
My AVDD, VDD and Excitation voltage is 5V.
So, if I choose a Load Cell with 1000 Ohms bridge resistance and 5mV/V then for 5V I get Load Cell output = 5mV * 5 = 25mV?
Currently I am simulating in Proteus and I am displaying just the raw ADC value of HX711 and for 1000 Ohms bridge resistance and 5mV/V Load Cell I am getting 16777215. How am I getting 2^24 for 25mV?
The datasheet
https://cdn.sparkfun.com/datasheets/Sensors/ForceFlex/hx711_english.pdf
mentions that for input channel A that is A+ and A then gain can be 64 or 128 and if 128 is chosen as gain then differential input can be +/40mV.
Does it mean that input can be 40mV to +40mV = 80 mV range?
80 mV = 2^24 = 0 to 16777215?
My AVDD, VDD and Excitation voltage is 5V.
So, if I choose a Load Cell with 1000 Ohms bridge resistance and 5mV/V then for 5V I get Load Cell output = 5mV * 5 = 25mV?
Currently I am simulating in Proteus and I am displaying just the raw ADC value of HX711 and for 1000 Ohms bridge resistance and 5mV/V Load Cell I am getting 16777215. How am I getting 2^24 for 25mV?
Attachments

178.7 KB Views: 12
Last edited: