Toshiba Electronics Components and Memory Devices Inc. announced the launch of the first two products in the overtemperature Detection IC ThermoflaggerTM series: "TCTH021BE" FLAG signal with no latch function when an abnormal state is detected, and "TCTH022BE" FLAG signal detection with latch function. They use positive temperature coefficient (PTC) thermistors to detect temperature rise inside electronic devices in simple circuit configurations.
The new IC comes in a compact, standard SOT-553 package (Toshiba's package name: ESV) with current consumption as low as 11.3μA (typical). In order for an electronic device to operate as prescribed, its semiconductor and electronic components must operate within the design parameters. Temperature is a key parameter, especially if the internal temperature is higher than the temperature assumed at the time of design. This can be a major concern in terms of safety and reliability, so an overtemperature monitoring solution is needed to detect any temperature rise.
The new ThermoflaggerTM IC is used in conjunction with a PTC thermistor to monitor resistance values based on temperature changes. They detect changes in resistance values of PTC thermistors placed near heat sources and output a FLAG signal to indicate overtemperature. The series PTC thermistor can realize overtemperature detection at multiple locations.