USB ADC 16 bits (averaging) test BL702
To operate USB BL702C, it is necessary to cut the wire in the area of contact (16) CH340C and solder the wire connecting contact (2) AMS1117-3.3 and contacts (4, 16) CH340C.
- ADC - GPIO_9 (mark D9)
- DAC - GPIO_17 (mark D17)
src/sdk2/project_bl702.bin - Test Firmware
TestsTools/adc/wso_adcs.html - ADC data reception via USB
DAC steps test on ADC (20 ksps, real 15 bits):
ADC scale 16 bits (0..65535)
Checking the ADC (20 ksps 16 bits) to GND through a resistor with a 1 uF electrolytic capacitor and checking with switching on to the INA199A1 output:
ADC scale 16 bits (0..65535)
To INA199A1
ENOB: 14,93 Bits
SNR: 91,63 dB
To GND
ENOB: 15.16 Bits
SNR: 93.02 dB
Checking the ADC (100 ksps 14 bits) to GND through a resistor with a 1 uF electrolytic capacitor:
ADC scale 14 bits (0..16383)
ENOB: 13.89 Bits
SNR: 85.38 dB
Comparison with a linear function
Nonlinearity and Noise
