DEM-SOT23LDO Positive LDO Regulator Eval Tool Texas Instruments DEM-SOT23LDO Positive LDO Regulator Evaluation Tool is a test fixture that helps designers evaluate the operation and performance of TI's Low-dropout (LDO) linear regulators. This test circuit fixture is compatible with most positive-output LDO regulators offered in the 5- or 6-lead SOT-23 package.