Other Parts Discussed in Thread: ADS54J60, ADS1115
I would like for someone to explain to me how the input voltages to the ADC's inputs (AINP, AINM, BINP, BINP) are supposed to work in the case of ADS54J60EVM.
In the ADS54J60 manual it is mentioned that the VIC (common-mode input voltage) is 2V while the input (full-scale) is 1.9Vpp. However, the absolute ratings for AINP, AINM, BINP & BINM are from -0.3V to 3.0V.
Unfortunately, there is no output code example in the manual. Furthermore, the ADS54J60EVM is supposed to work (if not modified) as single-mode. So, are the negative inputs (AINM & BINM) tied to the VCM (pin 22) which means that the reference voltage is 2.0V and not 0V (ground)?
So, is the (decoded) voltage range 1.05V to 2.95V to achieve 1.9Vpp? i.e.
1.) AINM = 2V, AINP = 2.95V, (AINP-AINN) = +0.95V
ADC output = 0x7FFF
2.) AINM = 2V, AINP = 1.05V, (AINP-AINN) = -0.95V
ADC output = 0xFFFF
Is this correct?
I would really appreciate a detailed example as the one Collin Wells gave on a similar case (but regarding a completely different Texas ADC).
Finally, after all the above is clarified, I would like to know if I can modify the output code to NOT use the full-scale, but rather a specific range (such as from -0.2V to +0.2V). This is crucial for the needs of my design as I would increase my SNR by being able to exploit the ADC's precision to my needs