85°C trip point — why that number matters for your thermal protection
The Maxim MAX6501UKP085-T is a micropower temperature switch that asserts its output when the die temperature crosses 85°C. That trip point is factory-set, so no external resistor divider or trim is needed — it's a fixed-threshold monitor for overtemperature events. The open-drain, active-low output (/OverTemp) pulls low when the threshold is exceeded, which directly drives a microcontroller interrupt or a power-good pull-down without level translation. Supply current is 30 µA typical, making it suitable for always-on thermal supervision in battery-operated gear.
Selectable hysteresis — stops the output from chattering near the threshold
The MAX6501UKP085-T includes selectable hysteresis, which means you can choose how much deadband the comparator has once the temperature drops back below 85°C. Without hysteresis, a sensor hovering near the trip point would oscillate on and off as the die temperature fluctuates by a fraction of a degree. The hysteresis value is set by a logic pin — the datasheet gives the specific delta, but the key takeaway for the BOM is that this part gives you the option to clean up the output without adding external RC filtering. The accuracy is ±6°C, so the actual trip point across temperature and supply sits between 79°C and 91°C worst-case. Budget that guard band when setting the system thermal limit.
Package and supply — fits a standard SOT-23-5 footprint
The part comes in a SC-74A / SOT-753 package, which is the standard SOT-23-5 footprint.
Lifecycle and compliance — active, but note the RoHS status
One catch for compliance tracking: this variant is listed as RoHS non-compliant. If your BOM requires RoHS-10 or REACH conformance, check the MAX6501UKP085+ (the lead-free suffix) or verify with your distributor that the date code meets your exemption.