ISOTMP35R

The ISOTMP35R is the industry’s first reinforced isolated temperature sensor IC, combining an integrated isolation barrier, up to 5kVRMS withstand voltage, with an analog temperature sensor featuring a 10mV/°C slope from –40°C to 150°C. This integration enables the sensor to be co-located with high-voltage heat sources (for example: HV FETs, IGBTs, or HV contactors) without requiring expensive isolation circuitry. The direct contact with the high-voltage heat source also provides greater accuracy and faster thermal response compared with approaches where the sensor is placed further away to meet isolation requirements.

Operating from a non-isolated 3V to 34V supply, the ISOTMP35R allows easy integration into applications where subregulated power is not available on the high-voltage plane.

The best output voltage of the ISOTMP35R ranges from 100mV to 2V for a –40°C to 150°C temperature range. The ISOTMP35R does not require any external calibration or trimming to provide a worst-case accuracy of ±0.5°C at room temperature and ±2.5°C over the full –40°C to 150°C temperature range. The linear output, 500mV offset, and factory calibration of the ISOTMP35R simplify the circuitry requirements in a single supply environment where reading negative temperatures is necessary.

The integrated isolation barrier satisfies UL 1577 requirements. The surface mount package (12-pin SSOP) provides excellent heat flow from the heat source to the embedded thermal sensor, minimizing thermal mass and providing more accurate heat-source measurement. This reduces the need for time-consuming thermal modeling and improves system design margin by reducing mechanical variations due to manufacturing and assembly.