The MCP9844T-BE/MNY comes in an 8-WFDFN exposed-pad package (8-TDFN, 2x3 mm body) — the exposed pad on the underside needs a thermal land on the PCB to pull heat from the die to the board plane. The 2x3 mm footprint is compact enough for DIMM SPD locations or tight module layouts.
Accuracy and output features for DIMM thermal management
The internal sensor feeds a sigma-delta ADC with a register bank, and the I²C interface lets the system controller poll temperature data and set alarm thresholds. The output alarm and fan-drive pins can trigger cooling without host intervention.
The -40°C to +125°C operating range matches industrial and server ambient temperature profiles, including the self-heating inside a fully loaded DIMM slot.
ROHS3 compliant, so it clears EU and China RoHS requirements without an exemption.