Is the MCP3202 clock frequency set right?
The ADC-DAC Pi Zero is a 2 Channel ADC and 2 Channel DAC for the Raspberry Pi
18/05/2016
Posted by:
jpsa
I could easily be confused here (I'm not an expert at reading datasheets, nor at using the spidev package!), but both the Python 2 and 3 libraries include the linespiADC.max_speed_hz = (4000000)(4 MHz). However the datasheet for the MCP3202 gives maximum clock speeds of 0.9 MHz at V_DD=2.7V, and 1.8 MHz at V_DD=5.0V.Certainly I'm getting much better results from the ADC side of the ADC DAC Pi if I reduce this max speed setting.
18/05/2016
Posted by:
andrew
Location:
United Kingdom
Thank you for spotting the mistake with the python libraries. You are correct the ADC clock speed should have been 0.9MHz.I have updated the python 2 and python 3 libraries with the correct clock rate.
19/05/2016
Posted by:
jpsa
Thank you!
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