Other Parts Discussed in Thread: ADS8319
Hello,
I am using two ADCs ADS8319 from TI and i have interfaced them with the ARDUINO UNO. The reference to both the ADC ICs have been provided by separate REF5050 ICs from TI.
There is a problem with output of both the ADCs.
At ADC1 i am giving input dc voltage value from 0V to 4.75V. The ADC output for this value range comes fine in the range of 0V - 3.5V, but when i increase the input to the ADC above 3.5V, the value starts to fluctuate, sometimes it shows the exact value(which is being given at the ADC input), and sometimes it shows a lower value and this starts to happen in a uniform manner, i.e the value keeps on bouncing in between the original value, and some lower constant value. But for the 0V - 3.5V input, it works perfectly fine.
At ADC2 i am giving the constant 2.5V input. And at the output of the ADC, the value is most of the times 2.5V, but also it goes to 0V after every 2 or 3 seconds, and it keeps on bouncing in between these two values ( 2.5V and 0V ).
I have used the value of input capacitor and resistors as recommended by the data sheet (5ohm, 1nF and 5ohm). I also changed the values of the input capacitor (from 1nF to 100nF, 0.1nF and 330nF), but it didn't solve the problem.
I have checked all my circuit connections, and made my circuit exactly as recommended by the data sheet, but i am unable to figure out the problem.
So PLEASE help !
I have attached my schematic diagram. ADC1 is taking its input from the MAX9922 amplifier, and ADC2 is taking its input from LTC2050 amplifier.
Thankyou.
