Precision 3.0 V shunt reference in SC-70-3
The LM4050CEX3-3.0+T: The shunt topology means it behaves like a Zener: you bias it through a series resistor from a higher rail, and the reference regulates by shunting current to ground. That 67 µA minimum cathode current sets the floor on the bias resistor — go lower and the reference drops out of regulation. Packaged in SC-70-3 (SOT-323 footprint), it takes up about 2.0 mm × 2.1 mm of board area — smaller than SOT-23, so it fits in dense mixed-signal chains where board space is the constraint. The 15 mA maximum output current limits the load you can drive directly; for anything heavier, buffer it with an op-amp or use a series reference instead.
Noise and drift — the real spec for ADC bias
Wideband noise from 10 Hz to 10 kHz is specified at 45 µVrms — that is about 15 ppm of the 3.0 V output. For a 12-bit ADC with a 3.0 V reference, 1 LSB at 12 bits is 732 µV, so the reference noise contributes roughly 6% of an LSB; for 16-bit (46 µV LSB), it dominates the noise budget and you'd want a lower-noise reference or post-filtering. That is within a quarter LSB at 12 bits but eats over 3 LSB at 16 bits — so this part is a solid fit for 10- to 12-bit precision applications but marginal for 16-bit without system calibration.
Active production, ROHS3, industrial temp range
Supplied in Tape & Reel (TR) or Cut Tape (CT) — the reel format is standard for pick-and-place assembly; cut tape suits prototyping or small-batch builds.
