Two over-temperature detection ICs kickstart Toshiba’s Thermoflagger family
Two over-temperature detection ICs are the first in the Thermoflagger family launched by Toshiba Electronics Europe. The devices can be combined with positive temperature co-efficient (PTC) thermistors to detect over-temperature conditions within electronic systems. They are intended for use in a wide range of applications including mobile devices, home appliances and industrial equipment.
Thermoflagger devices offer a simple and inexpensive, low current consumption solution capable of connecting to several PTC thermistors, explained Toshiba. Additional over-temperature protection solutions can be realised by combining them with general temperature sensor ICs.
The family’s initial devices are the TCTH021BE, which has a non-latching function for the ‘flag’ signal when it detects abnormal states, and TCTH022BE, which has a latching function for the signal.
The TCTH021BE and TCTH022BE Thermoflagger ICs each have a built-in current source and are used in combination with PTC thermistors which raises their Ohmic resistance values significantly once a certain temperature level has been exceeded. An increasing temperature close to any PTC will cause the voltage to rise at the PTCO pin, resulting in the flag signal being activated to detect an over-temperature condition. By connecting multiple thermistors in series, over-temperature detection for multiple locations is possible, explained Toshiba.
The ICs are housed in the small, standard SOT-553 package (ESV) measuring just 1.6 x 1.6 x 0.55mm. They feature a low current consumption (IDD10U) of 11.3 microA (typical). The PTCO output current can be selected. Typically, IPTCO is 10 microA with ± eight per cent accuracy.
Operating supply voltage (VDD) can be in the range 1.7 to 5.5V and the devices can operate at temperatures between -40 to +125 degrees C.
Both the TCTH021BE and TCTH022BE Thermoflagger ICs allow users to configure over-temperature detection for an electronic device without significantly impacting the size and power consumption, added Toshiba.
Both products are shipping now.
