Toshiba Announces Thermoflagger™, a Simple Solution that Detects Temperature Rises in Electronic Equipment

May 16, 2023

Toshiba Electronic Devices & Storage Corporation

KAWASAKI, Japan—Toshiba Electronic Devices & Storage Corporation ("Toshiba") has launched the first two products in its Thermoflagger™ over-temperature detection IC series: “TCTH021BE,” which does not have a latching function for the FLAG signal when it detects abnormal states; and “TCTH022BE” which does have a latching function. They detect temperature rises inside electronic equipment in a simple circuit configuration with positive temperature coefficient (PTC) thermistors. Shipment starts today.

For electronic equipment to perform as specified, their semiconductors and electronic components must operate within design parameters. Temperature is one crucial parameter, especially if the internal temperature becomes higher than that assumed during the design process. This can be a major problem in respect of safety and reliability, and requires an overheating monitoring solution to detect any rise in temperature.

The new Thermoflagger™ ICs are used in combination with PTC thermistors that change their resistance values according to the temperature. They detect changes in the resistance value of a PTC thermistor placed close to heat sources, and output FLAG signals to indicate over-temperature. Connecting PTC thermistors in series realizes over-temperature detection for multiple locations. 

The new ICs are housed in the small, standard SOT-553 package (Toshiba’s package name: ESV) and feature a low current consumption of 11.3μA (typ.).

A reference design "Over Temperature Detection IC Thermoflagger™ Application Circuit" using the new ICs is available now.

Thermoflagger™ ICs allow users to configure over-temperature detection for an entire electronic product easily, and help to reduce its size and power consumption. Toshiba will continue to develop Thermoflagger™ ICs with various functions.

Toshiba Announces Thermoflagger™, a Simple Solution that Detects Temperature Rises in Electronic Equipment
Image 1: Thermoflagger™ over-temperature protection solution
Image 1: Thermoflagger™ over-temperature protection solution
Image 2: Sample circuit board for Thermoflagger™ TCTH021BE
Image 2: Sample circuit board for Thermoflagger™ TCTH021BE


  • Mobile devices (laptop PC, etc.)
  • Home appliances
  • Industrial equipment, etc.


  • Simple configuration to combine with PTC thermistors
  • Overheat can be monitored at several points by connecting PTC thermistors in series.
  • Low power consumption: IDD10U=11. 3μA (typ.)
  • Small and standard package: SOT-553 (ESV)
  • Selectable PTCO output current: IPTCO=10μA (typ.)
  • High PTCO output current accuracy: ±8% (VDD=3.3V, 25°C)
  • FLAG signal output (PTCGOOD)

Main Specifications

(Unless otherwise specified, Tj=25°C) 

Part number TCTH021BE TCTH022BE
Packages Name SOT-553 (ESV)
Size typ. (mm) 1.6×1.6, t=0.55
Operating ranges Supply voltage VDD (V) 1.7 to 5.5
Operation temperature Topr (°C) -40 to 125
Electrical characteristics PTCO output current IPTCO (μA) typ. 10
Detect voltage VDET (V) typ. 0.50
Current consumption IDD10U (μA) typ. 11.3
UVLO voltage VUVLO (V) typ. 1.5
FLAG signal output PTCGOOD Open-drain type
Latching function for FLAG signal when abnormal states are detected No Yes
Sample Check & Availability Buy Online Buy Online

Follow the links below for more on the new products.

Follow the link below for more on Toshiba’s Thermoflagger™

Thermoflagger™ (Over temperature detection IC)

Follow the links below for more on Toshiba’s solutions proposals using the Thermoflagger™

Solid State Drive
Tablet Device

To check availability of the new products at online distributors, visit:

Buy Online

Buy Online

Customer Inquiries:

* Thermoflagger™ is a trademark of Toshiba Electronic Devices & Storage Corporation.
* Other company names, product names, and service names may be trademarks of their respective companies.

Information in this press release, including product pricing and specifications, content of services and contact information, is current and believed to be accurate on the date of the announcement, but is subject to change without prior notice. Technical and application information contained here is subject to the most recent applicable Toshiba product specifications.

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