1.235 V fixed shunt reference — active and in production
It delivers a stable output with a typical temperature coefficient of 20 ppm/°C and an initial tolerance of ±2%.
Output current and cathode current — bias design limits
Rated for 20 mA maximum output current, the LM385LPRE3-1-2 can supply moderate loads. The minimum cathode current is 15 µA, which sets the lower bound for the bias resistor in a shunt configuration — design the bias current above this floor to maintain regulation. The 60 µVrms noise spec (10 Hz to 10 kHz) gives a baseline for low-noise analog paths; the shunt topology itself adds no series noise, so the reference's own noise floor is the limit.