Resistor-programmable temperature switches protect against system thermal events

03-09-2019 | Texas Instruments | Connectors, Switches & EMECH

Texas Instruments TMP390 Resistor-Programmable Temperature Switches are dual-channel, ultra-low power, resistor programmable temperature switches. These switches facilitate protection and detection of system thermal events from –50C to 130C. The device offers independent over-temperature (hot) and under temperature (cold) detection. The trip temperatures and thermal hysteresis options are programmed by two E96-series (1%) standard decade value resistors on the SETA and SETB pins. Each resistor can range from 1.05KOhm to 909KOhm, representing one of 48 unique values.

The values of the resistor to ground on SETA input sets the TTRIP threshold of Channel A. The value of the resistor to ground on SETB input sets the TTRIP threshold of Channel B, as well as the THYST options of 5C, or 10C for both channels, to stop undesired digital output switching. Resistors accuracy has no impact to TTRIP accuracy. To facilitate customer board-level manufacturing, the device supports a trip test function where the digital outputs are initiated by exercising the SETA or SETB pin.

Typical applications solutions include DC/AC inverter, DC/DC converter, temperature transmitters, environmental control systems, power tools, power banks; wireless infrastructure including WLAN/Wi-Fi access points, core routers, edge routers, and macro remote radio units.

By Natasha Shek