1. Relate coding to the analog range
An ADC delivers a digital word, but the word's meaning depends on the relationship specified between codes and the analog input range. Analog Devices makes that range connection explicit in its converter-code tutorial. Start a sourcing comparison with the analog quantity being represented and its documented span. A bit count describes the word's resolution, not the complete convention for interpreting it.
A requirement for positive-only measurements and a requirement representing quantities on both sides of a reference have different interpretation questions. The code convention must be read in that stated range context. Do not transfer a familiar zero or full-scale assumption from another converter merely because the replacement has the same word length. The exact device's documented representation remains part of its functional interface.
This makes coding a system-interface decision as well as an ADC description. The receiving software must interpret the word in the convention the selected converter supplies. A sourcing line that preserves resolution but drops coding can conceal a change in numerical meaning. Identifying that change requires neither a bit-pattern table nor a calculation; it requires retaining the specified range and representation together.
2. Distinguish straight and offset binary meaning
ADI describes straight binary in its discussion of unipolar conversion and offset binary in its discussion of signed analog quantities. These are related binary representations, but the analog interpretation differs. Keeping the names explicit prevents a host's familiar unsigned interpretation from silently becoming the assumed meaning for a converter described using an offset convention.
The practical comparison asks what the receiving application expects from the converter word. If the established interpretation assumes one convention, a candidate documented with another introduces a real interface question. That does not make either convention inherently more accurate. It means the numerical interpretation must remain consistent across the converter description and the host's released treatment of the measurement.
A generic statement that both products output binary data is insufficient. It discards the very distinction being compared. Equally, no universal endpoint mapping should be inferred from the convention name alone without the exact range definition. This guide keeps the representation terminology intact while leaving device-specific code mapping, exceptional output meanings and any implementation work with their applicable documentation.
3. Keep twos-complement signed interpretation explicit
Twos complement is another representation used for signed quantities in ADI's discussion. Its numerical interpretation differs from treating the same received word as offset binary. An interface comparison should name that difference directly. The fact that both conventions can represent positive and negative measurements does not make an unchanged interpretation correct for both.
The tutorial explains why twos complement is useful in computing contexts, but recognizing that role is not a software conversion recipe. The sourcing question is which convention the converter provides and which convention the receiving system expects. Any required processing change belongs to the engineering implementation review. No arithmetic, bit manipulation or example code is supplied here to make an unreviewed substitution appear complete.
Retain the convention wherever the data crosses a system boundary. A description can become ambiguous when a converter output is passed through an interface layer and the original coding name disappears. Naming the received format and the expected interpretation keeps that ambiguity visible. It does not establish how a particular host stores, extends or processes the word; those are additional implementation details.
4. Separate code meaning from framing and measurement accuracy
Serial framing answers how a word is transferred. Coding answers what its data represents. A successful transfer in the expected frame therefore does not establish that the receiving application assigns the correct signed or range-related meaning. Compare these responsibilities separately: the word must arrive in the applicable transport format and be interpreted using the converter's stated coding convention.
Measurement timing adds further independent questions. Sampling architecture concerns the relationship between channel observations; clock jitter concerns capture-time uncertainty; acquisition and filter latency concern different settling processes. A correct code interpretation does not resolve those mechanisms. Conversely, good evidence about sampling or settling cannot repair a mismatched numerical interpretation simply because the received measurements appear plausible.
A useful requirement identifies the analog range, output coding and receiving interpretation before assessing accuracy claims. Those inputs make a proposed representation change visible without pretending that coding determines achieved precision. Ask whether the exact candidate and existing host agree on meaning, then retain any required interface review separately. This article provides no code table, endpoint formula, interface command or result for an actual measurement chain.
Sources and further reading
ADI MT-009 saved text on physical pages 3, 7, 8 and 9 was reread within the declared scope. Figures, bit tables and arithmetic were not used to derive claims. No universal endpoint mapping, conversion code, whole-document review or measured ADC result is supplied.