24-TSSOP footprint and board integration
The LM81BIMT-3/NOPB: The tube delivery means the ICs are shipped in antistatic tubes, not tape-and-reel — factor this into pick-and-place feeder setup if your line expects reeled parts.
What ±3°C max accuracy means for your thermal monitoring
For a system that needs to trigger a fan or an alarm at a specific temperature threshold, this tolerance means the actual trip point can be up to 3°C away from the programmed value. If your thermal budget requires tighter control — say, ±1°C at a critical junction — you may need to calibrate the remote diode path or select a higher-grade monitor. For most equipment monitoring (server racks, power supplies, industrial controllers), ±3°C is adequate to prevent thermal runaway without nuisance alarms.
Active production — no end-of-life concern
Texas Instruments lists the LM81BIMT-3/NOPB with a lifecycle stage of 'current' and an official product status of 'Active'. The part is ROHS3 compliant, so it meets the EU RoHS directive without exemption.
Internal architecture: ADC, comparator, fan control, register bank
The LM81BIMT-3/NOPB integrates a sigma-delta ADC, a comparator, fan speed control logic, and a register bank. The sigma-delta ADC converts the analog voltage from the internal temperature sensor and the external diode-connected transistor into a digital value. The comparator checks the converted temperature against programmable limit registers and asserts the ALERT output if a limit is exceeded. The fan speed control block generates a PWM or linear output to drive a cooling fan based on the temperature reading — this closes the loop without host processor intervention. The register bank is accessed over the 2-wire SMBus for configuration and readback.
Supply rail and operating range
This covers most equipment environments except extended military or downhole applications.
