The MAX6071BAUT41+T is a 4.096 V series voltage reference in a SOT-23-6 package. The 4.096 V output is a deliberate choice for bipolar ADC ranges — it maps directly to a ±10 V input after a 1:4 gain stage, or to a 0–4.096 V unipolar range without scaling resistors. Initial accuracy is ±0.08% — that is ±3.3 mV at the reference pin. For a 16-bit ADC with a 4.096 V reference, this error consumes roughly 0.08% of the full-scale range, leaving the rest of the budget for the ADC's own INL and the signal-chain gain error. Temperature drift is 8 ppm/°C. Combined with the initial tolerance, the worst-case reference error over temperature is about ±0.19% — enough to degrade a 12-bit system but manageable for a 16-bit design with a calibration step at the board level.
Noise floor and load drive
The 0.1–10 Hz band is the one that matters for DC-precision measurements — a 9.6 µVp-p noise floor at the reference translates to roughly 1.5 LSBs of peak-to-peak noise on a 16-bit ADC at 4.096 V, so the reference itself is not the dominant noise source in a well-laid-out signal chain. Output current is rated 10 mA — enough to drive the reference input of a single SAR ADC plus a small buffer, but not enough to power multiple converters or a heavy analog front-end without an external op-amp. Supply current is 350 µA typical, which keeps the self-heating contribution to the drift budget under 1 ppm/°C in still air.
Input headroom and board integration
The 4.096 V output needs at least 204 mV of dropout — a 5 V rail with ±5% tolerance drops to 4.75 V, leaving 654 mV of headroom, which is safe. A 3.3 V rail cannot drive this part; the reference needs its own 5 V supply or a boost converter. The SOT-23-6 package (SOT-6 supplier device package) is a standard footprint with 0.95 mm pitch. The small body means the thermal resistance to ambient is higher than a SOIC-8 — expect about 200°C/W in still air, so the 350 µA supply current plus 10 mA output at 4.096 V (41 mW total) raises the die temperature roughly 8°C above ambient, well within the -40°C to +125°C rating.
