Interested parts: LTC2512-24
I'm looking for a high-precision ADC with the specification below:
|SNR||> 100 dB, the larger the better|
|INL||about 1 ppm acceptable|
|Bandwidth||> 3 kHz|
I prefer SAR+FIR type ADC because it seems to have better sampling accuracy (I guessed because I heard that the SAR takes snapshots). But delta-sigma is also ok.
My input type is true-bipolar single-ended. The single-ended is acceptable in LTC2512's datasheet because of the 130dB CMRR, but the typical application chapter uses a single-to-differential converter. Can I infer that ADI recommends the differential input to achieve the performance written in the datasheet?
I found that there's no precise SAR+FIR ADC supporting the true-bipolar input. I wonder the reason (because of the SAR architecture?). How can I convert my true-bipolar signal to a bipolar signal? Will this conversion circuit significantly lower the ADC's SNR? (If so, I'll choose a delta-sigma one that supports the true-bipolar input)