It delivers a stable 1.235 V output with ±2% initial tolerance and a typical temperature coefficient of 20 ppm/°C.
Cathode current and output drive
The shunt can sink up to 20 mA of output current, but the real design constraint is the minimum cathode current of 15 µA. Below that, the reference drops out of regulation. For a 1.235 V rail pulling 1 mA, a 1.2 kΩ series resistor from a 3.3 V supply biases the shunt well above the 15 µA floor. The 60 µVrms noise spec (10 Hz to 10 kHz) is clean enough for most ADC references in the commercial temperature band.