Fixed 3 V rail with ±0.4 % initial accuracy
The MAX6034BEXR30+T is a series voltage reference from Analog Devices that outputs a fixed 3 V with a ±0.4 % initial tolerance. That ±12 mV window at 25 °C is the starting point for the ADC or DAC reference rail — the system's full-scale error budget starts here.
Noise floor and temperature drift — the real limits
For a 16-bit ADC with a 3 V reference, the noise contribution from the reference alone eats about 0.5 LSB at the 10 Hz bandwidth; above that the wideband noise starts to dominate the signal chain floor. In an industrial sensor module that sees a 60 °C swing, the reference drifts about 13.5 mV — the system must budget this into the gain or use a ratiometric measurement topology to cancel it.
Supply headroom and load current budget
Input voltage range is 3.2 V to 5.5 V, giving 200 mV of dropout headroom above the 3 V output at the low end. The reference can source up to 1 mA to the load while drawing 125 µA quiescent current from the supply — the 1 mA output is the hard ceiling; pulling more drops the output out of regulation. The SC-70-3 (SOT-323) package footprint is shared with many low-power references and op-amps — the layout can reuse a standard three-pin SOT-23-3 pad with minor adjustment for the narrower body width.