The over-temperature detection ICs can be combined with positive temperature coefficient (PTC) thermistors to detect over-temperature conditions within electronic systems. They are suitable for a wide range of applications including mobile devices, home appliances and industrial equipment.

The TCTH021BE has a non-latching function for the ‘flag’ signal when it detects abnormal states and the TCTH022BE has a latching function for the signal.

The simple and inexpensive, low current consumption ICs can be connected to several PTC thermistors. Additional over-temperature protection solutions can be realised by combining them with general temperature sensor ICs.

The TCTH021BE and TCTH022BE Thermoflagger ICs products each have a built-in current source and are used in combination with PTC thermistors which elevates their Ohmic resistance values significantly once a certain temperature level has been exceeded, says Toshiba. An increasing temperature close to any PTC will cause the voltage to rise at the PTCO pin, activating the flag signal, signalling an over-temperature condition. By connecting multiple thermistors in series, over-temperature detection for multiple locations is possible.

The ICs are housed in Toshiba’s ESV, small, standard SOT-553 package measuring 1.6 x 1.6 x 0.55mm. They feature a low current consumption (IDD10U) of 11.3μA (typical) and the PTCO output current can be selected. Typically, IPTCO is 10μA with accuracy of ±8%.

Operating supply voltage ranges from 1.7 to 5.5V and the devices can operate at temperatures between -40ºC to 125ºC.

Both ICs allow users to configure over-temperature detection for an entire electronic device easily without significantly impacting the size and power consumption of the device.

Both products in the TCTH0xxxE series will start shipping today.