Murata Manufacturing Co., Ltd. has commercialized the industry's tightest tolerance (±3°C) 1005 size 1 kΩ Series Overheat Detection Chip PTC Thermistor*1.
This product will be displayed at CEATEC2011 held at the Makuhari Messe from October 4 to 8.
As cell phones, tablet PCs, LED lighting, and other such devices become more and more popular, they are also becoming increasingly smaller and higher-output. This has led to an increasing need for countermeasures against heat in these devices, and especially a rising need for PTC thermistors that can detect overheating in simple circuits.
Overheat detection chip PTC thermistors up until now have generally been larger than 1.6x0.8 mm and the detection temperature*2 tolerance higher than ±5°C. We used our original technology and processing techniques to produce the 1 kΩ Series Chip PTC Thermistor that is only 1.0x0.5 mm and has a detection temperature tolerance of only ±3°C. Our product lineup includes products with a detection temperature between 80°C and 150°C in 10°C steps.
- Small size (1.0x0.5 mm)
- Tight tolerance (±3°C at 100 kΩ, ±5°C at 10 kΩ)
- Detection point series (between 80°C and 150°C at 100kΩ, between 65°C and 135°C at 10kΩ with 10°C steps)
- TUV, UL approved
- Overheat detection of LED lights, power control
- Overheat detection for MOSFET*3 in notebook PC's dispersed power source DC-DC converter and overheat detection for MOSFET in lithium ion battery protection circuit
- Overheat detection and power control of inverters and coils in motors
||A resistor whose resistance varies with temperature. In a conventional NTC thermistor, the resistance decreases slowly as the temperature increases, but the Positive Temperature Coefficient (PTC) thermistors' (POSISTOR®*4) resistance rises sharply when its temperature exceeds a specific temperature (Curie temperature*5). In addition to use in overheat detection, they can also be used to control current or power by utilizing a unique resistance temperature curve.
|*2 Detection temperature:
||For this product, we recommend detection of the temperature reached when the thermistor resistance is either 10 kΩ or 100 kΩ.
||Metal-Oxide-Semiconductor Field-Effect Transistor
The MOSFET is used as the switching element of DC-DC converters or as a general-purpose current switch. When the FET is operated at a higher temperature than specified, the FET can become damaged. Damage to the FET can be prevented by detecting whether it is overheating with a POSISTOR® overheat detection chip.
||POSISTOR® is a trademark of Murata Manufacturing
|*5 Curie temperature:
||Also called the Curie Point (C.P.). Murata Manufacturing defines it as the temperature reached when the resistance doubles that at 25°C.
|Detection temperature at 10kΩ
||Detection temperature at 100kΩ
Commercial production began in March 2011 at the Murata Manufacturing Yokaichi Plant
10 yen per unit
Murata Manufacturing Co., Ltd. is a worldwide leader in the design, manufacture and sale of ceramic-based passive electronic components & solutions, communication modules and power supply modules. Murata is committed to the development of advanced electronic materials and leading edge, multi-functional, high-density modules. The company has employees and manufacturing facilities throughout the world. For more information, visit Murata's website at www.murata.com