4.096 V ±0.1% — the precision anchor for ADC and DAC rails
The Texas Instruments REF5040AIDGKT is a precision series voltage reference that outputs a fixed 4.096 V with an initial accuracy of ±0.1%. This output voltage is a common full-scale reference for 12- to 16-bit SAR ADCs and multiplying DACs, where the 4.096 V level directly maps to a 1 mV LSB in a 12-bit system. The series topology means it needs no external resistor to set the output, and it remains stable with as little as 4.296 V on the input, making it usable from a 5 V rail with margin for regulation dropout.
3 µVp-p noise at 0.1–10 Hz — what it means for converter SNR
In a 4.096 V reference feeding a 16-bit ADC with 65,536 codes, this noise contributes roughly 0.5 LSB of uncertainty at the converter's noise floor — a clean reference that doesn't eat into the signal chain's dynamic range. The 8 ppm/°C temperature coefficient means the output shifts about 33 µV over a 100°C swing, which is under 1 LSB at 12 bits but worth budgeting for 16-bit designs.
10 mA output — driving multiple converter reference inputs
The reference can source up to 10 mA of output current. That's enough to drive the reference inputs of several simultaneous-sampling ADCs plus any necessary decoupling capacitors without an external buffer. Quiescent supply current is 1.2 mA typical, so the total current drawn from the input rail is dominated by the load, not the reference itself. The wide input range from 4.296 V to 18 V allows operation from 5 V, 9 V, or 12 V rails without a separate pre-regulator.
Active production — no end-of-life risk on this BOM line
For a precision reference that often gets locked into a calibrated BOM, this is the right lifecycle posture: you can qualify it for new designs and expect multi-year supply without a forced respin.
Package and temperature grade — surface-mount fit for industrial environments
Housed in an 8-VSSOP package (3.00 mm width, 0.118" pitch), the part is a surface-mount device suited for automated assembly. The supply voltage rating (4.296 V minimum) means a 5 V rail with ±5% tolerance still keeps the reference in regulation, even during brownout conditions.
