Hi Fausto, Pretty much everything you need to know is in the datasheet, but I understand that it may not be clear or easy to find. See my responses below: [quote user="Fausto Bartra1"]Thanks Bob: I check all you have mentioned above. I am getting the proper readings back from the ADC, but the time it takes for the next conversion is 125ms ??? (.i.e. DRDRYn pin goes low again) [Bob] This really depends on the master clock frequency you are using and the register settings. 125ms period is 8sps data conversion rate. The data rate (fdata) is defined and the calculation shown on the DEFINITIONS section on page 32 of the datasheet. Basically the data rate is fmod/Decimation Ratio. The decimation ratio is in 2 registers as an 11 bit value and the default is 0x780 (1920 decimal). The fmod is fosc/128, so if the oscillator frequency is 2.4576MHz, the fmod frequency is 19200 and the data rate at 10sps (19200/1920). So depending on the actual clock frequency you appear to be close to this data rate. A 2MHz clock would be about 8sps. it will help a lot if you could email me more info on this device........ otherwise, Here are some questions: 1.-is there any documentation on how to use the DSYNC pin? (timing diagram..etc)? [Bob] DSYNC timing diagram is on page 9 of the ADS1216 datasheet and the explanation is on page 19 under DSYNC OPERATION. 2.-Also what are the FSR registers for?? [Bob] These are the Full-Scale calibration registers used for gain correction. You would generally not write to these register as the device will automatically write to the FSC and OCR (offset calibration) registers following a calibration command. This information is found on page 17 in the CALIBRATION section. The self calibration commands are SELFCAL, SELFOCAL and SELFGCAL and are listed in the COMMAND DEFINITIONS on page 26. 3.-Does the DRDYn pin need a pull up? [Bob] No, as DRDY is an active push-pull output. 4.-can analog input be from 0V to 5V for VREF = 2.5V internal, AVDD =5V, DVDD=3.3V, Buffer = disable? [Bob] The full-scale input range is given in the Electrical Characteristics table on page 3 for 5V AVDD. See the discussion on Full-Scale Range on page 33 of the datasheet. With the PGA setting at one, the FSR is 5V (or +/-2.5V), so in unipolar mode you can measure 0 to 5V from the information you provided. 5.-What is the conversion time?? [Bob] See my answer above. Thank you again Fausto Bartra [/quote] Best regards, Bob B
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