Part Number: AFE4404 Hi, I am working on calibration code for AFE4404 + SFH7072. I've encountered the following problem. 1) Even though OFFSET values were 0(ambient offset or DC offset), minus ambient values were measured during calibration. The values were not big values - like -690 ~ -1000. Is this normal ? Rf=250K, ILED was about 10(red or IR). Measured at finger tip. 2) Another case: Ambient values were very big like 230000 while red/ir values were 1450000 or so. This is weird because I pressed the sensor tight enough with my thumb so that no ambient light can come in. Strangely if the red/ir values were subtracted by the ambient values, the values were near the target threshold values, 0.6V. In this case, OFFSET values were 0. Can somebody explain it ? PD module was out of order or AFE4404 was not set properly ? Thanks for your advice. Konan
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