10mV/°C analog output — what the resolution means for your ADC
The LM45CIM3X-NS outputs a linear analog voltage scaled at 10mV/°C, so at 25°C the output sits at 250 mV (typ). This direct scaling means no external reference or gain stage is needed for a basic microcontroller ADC — the 10-bit count at 3.3 V reference reads roughly 0.8 counts per °C, giving sub-1°C digital resolution. Accuracy is specified as ±3°C at 25°C, with a ±4°C band across the full -20°C to 100°C range. That ±4°C window is the total uncalibrated error — the sensor's own offset plus the output slope tolerance. For a system that trims at one temperature, the residual error drops to the slope tolerance (roughly ±1°C).
SOT-23-3 package and surface-mount footprint
Housed in a standard SOT-23-3 (TO-236-3 / SC-59) package, the LM45CIM3X-NS occupies a 2.9 mm × 1.3 mm footprint with 0.95 mm pin pitch. The three pins — V+, GND, and Vout — map to a simple layout: a 100 nF bypass cap within 5 mm of the V+ pin keeps the supply clean for the analog output. The supply range of 4 V to 10 V lets it run from a common 5 V rail or a 9 V battery without an extra regulator. At 4 V the output at 100°C is 1.0 V, leaving headroom above the 0.8 V dropout of many LDOs — so a 3.3 V system needs a rail-to-rail ADC or a level shifter.
Active production, RoHS non-compliant — sourcing reality
Texas Instruments lists the LM45CIM3X-NS as Active, so it remains in the factory portfolio and is not subject to a last-time-buy or EOL notice. However, the RoHS status is marked non-compliant — this part contains lead (Pb) in the solder finish or die-attach above the exemption threshold. That means it cannot ship into RoHS-restricted regions (EU, UK, California) unless covered by an exemption, but it is fully acceptable for military, aerospace, or industrial equipment with a RoHS waiver. Because it is a mature, active part with a non-compliant finish, stock turns over slowly through authorized channels. Sourcing is confirmed per RFQ — we verify date-code consistency and traceability from the authorized chain to avoid re-marked or sanded units that sometimes appear on the spot market for legacy temp sensors.