The Texas Instruments LM4051CIM3X-1.2 is a precision shunt voltage reference delivering a fixed 1.225V output with ±0.5% initial tolerance. It is designed for low-power bias and reference applications where a stable voltage rail is needed without a series regulator — the shunt topology sinks current through the cathode to regulate the output, so it behaves like a Zener but with tighter accuracy and lower drift. The 50 ppm/°C temperature coefficient means the output voltage shifts by roughly 61 µV per °C — acceptable for 12-bit ADC references but marginal for 16-bit systems without calibration. The 65 µA minimum cathode current and 12 mA maximum output current cover bias loads.
Sourcing an obsolete precision reference
No official direct replacement is recorded for this order code.
Package and footprint — SOT-23-3 layout notes
The three-pin layout — cathode, anode, and no-connect — matches the standard shunt reference footprint.