2.048 V shunt reference with ±0.2% initial accuracy
The Texas Instruments LM4040BIZ-2.0/NOPB is a precision shunt voltage reference delivering a fixed 2.048 V output with a ±0.2% initial tolerance. This is a B-grade device in the LM4040 family, intended for applications requiring a stable, low-noise voltage reference without the complexity of a series regulator topology. The shunt architecture means the part operates as a two-terminal device — it sinks current through the cathode to regulate the output voltage, with a minimum cathode current of 65 µA and a maximum output current of 15 mA. The 35 µVrms noise over 10 Hz to 10 kHz makes it suitable for biasing precision ADCs or sensor bridges where low-frequency noise matters. The TO-92-3 through-hole package (TO-226AA) is a legacy form factor — board layouts must accommodate the leaded footprint.
Procurement for this part runs through the surplus and independent distribution channel. For a pin-compatible replacement within the same family, the designer should evaluate the current-production LM4040 variants in the same TO-92-3 package — the LM4040AIM3-2.0 or LM4040CIM3-2.0 are common alternatives, though tolerance grades and temperature ranges differ. Confirm the exact parametric match against the BOM requirements before substituting.
TO-92-3 through-hole — legacy footprint considerations
The TO-92-3 (TO-226AA) package is a three-lead through-hole form factor with 0.100-inch (2.54 mm) lead spacing. This package is not suitable for high-density surface-mount designs; it requires a drilled PCB with plated through-holes and is typically hand-soldered or wave-soldered. This is consistent with through-hole components and does not affect the electrical performance, but it does affect automated pick-and-place handling: the part is not feeder-compatible without manual loading or a tube feeder.