Adjustable output — 1.24 V to 5.3 V
The LM385MX: This is a shunt-type voltage reference with an adjustable output from 1.24 V minimum up to 5.3 V maximum, set by two external resistors.
20 mA output, 55 µA cathode current
The LM385MX can source or sink up to 20 mA, which is enough to bias an ADC reference input or a comparator threshold divider. The minimum cathode current is 55 µA — keep the bias resistor sized so the total current through the shunt stays above that floor or the output voltage drifts out of regulation. The 50 µVrms noise (10 Hz to 10 kHz) is low enough for 12-bit systems without an external filter cap.
8-SOIC — field-swap note
Housed in an 8-SOIC (0.154″ wide, 3.90 mm body), the LM385MX is a surface-mount part you can swap with a standard hot-air station or a fine-tipped iron if the board has enough pad access. No exposed pad, no thermal vias — just eight leads. The pinout is the same as the industry-standard LM385 in SOIC-8, so a rework tech can pull the old part and solder this one without checking a footprint drawing.