5V ±0.1% — the reference that sets the ADC LSB budget
That 0.1% figure is the starting accuracy before temperature or aging; for a 16-bit ADC with a 5 V reference, the initial error consumes about 32 LSBs of the total error budget, leaving the rest for drift, noise, and the converter itself. It is a series reference, meaning it regulates the output by controlling a pass transistor rather than shunting current to ground. This topology delivers lower quiescent current — 1.2 mA supply current typical — and better load regulation than a shunt reference, especially when the load varies.
8 ppm/°C drift and 3 µVp-p noise — the thermal and noise floor
The temperature coefficient is 8 ppm/°C maximum. For a 5 V system, that is roughly 0.026% of full scale — well within the margin for a 14-bit or 16-bit ADC if the reference is kept near the converter. This band covers the flicker noise that dominates in precision DC measurements; 3 µVp-p is low enough that a 16-bit ADC (76 µV LSB at 5 V) sees negligible reference noise contribution. No external noise filter is needed in most designs, though a 1 µF to 10 µF bypass at the output pin is still standard practice — page 12 of the datasheet shows the recommended layout.
10 mA output — driving the ADC reference input and more
The REF5050AIDGKR can source up to 10 mA. That is enough to drive the reference input of most SAR ADCs (which draw microamps to a few milliamps during conversion) while also supplying a small external load like a precision divider or a buffer. If the total load exceeds 10 mA, the output drops out of regulation — derate for temperature as the datasheet's safe-operating-area curve shows. Input voltage range is 5.2 V to 18 V, giving plenty of headroom for a 5 V output. The dropout voltage is about 200 mV at light load, so a 5.2 V rail is the practical minimum — a 5 V rail cannot feed this part. The wide input range also makes it usable in systems with unregulated supplies, such as 12 V or 15 V industrial buses.
8-VSSOP package — footprint and thermal reality
The 8-VSSOP (also called 8-MSOP with 0.118-inch body width) is a 3.00 mm × 3.00 mm body with 0.65 mm pin pitch. Surface-mount only — no through-hole variant. For a 1.2 mA supply current at 18 V input, power dissipation is about 15.6 mW, so self-heating is negligible — the junction stays within a degree or two of ambient.