We have been using mercury thermometers since we were young. Although the measurement accuracy is high, it is indeed unsafe. Once it cannot be cleaned up in a timely manner, it poses great harm to human health. Therefore, electronic thermometers, ear temperature guns, and frontal temperature guns can be chosen to measure body temperature. When measuring body temperature with a frontal thermometer, the infrared energy released by the human body is used for measurement. The frontal thermometer can avoid cross infection and has a fast temperature measurement speed, making it particularly suitable for people with fever symptoms. Recently, with frequent outbreaks of diseases, timely temperature measurement and monitoring of one's own health status have become a must-have for everyone. Tuyang Technology adopts Jerry's ultra-low power Bluetooth intelligent chip, rich intelligent compatible design, compatible with multiple devices, and combined with infrared sensing temperature compensation algorithm, temperature measurement is doubly accurate. Based on the above principles, you may find that a forehead thermometer can measure body temperature without touching the skin, and the time is relatively short. Isn't this perfect? In fact, there are also some problems with forehead temperature guns because they do not come into contact with the skin, so their impact on temperature and wind speed may be slightly greater than mercury thermometers or temperature guns. However, without touching the human body, they can avoid cross infection and quickly detect fever symptoms. Therefore, forehead temperature guns have become irreplaceable products.

Tuyang Technology | Intelligent forehead temperature gun solution

Intelligent forehead temperature gun solution

In order to expand the temperature measurement range, the battery voltage is first converted to 3V, and the entire system is powered by high-voltage LDORS3002. The system uses backlight, transmission and other equipment for power supply, and then uses low-power LDORS3236 to reduce from 3V to 1.5V. Its purpose is to provide a reference voltage for the thermoelectric stack, thereby improving the entire measurement temperature range. In order to accurately calculate at different ambient temperatures, the microcontroller must also read the current ambient temperature. The specific implementation method is to read the NTC resistance inside the thermoelectric stack and set the voltage point to 100k Ω.

Due to the high output impedance of the transmission section, it is recommended to use an in-phase amplification circuit topology to achieve an amplification factor of over 100 times. Therefore, it is necessary to reserve a low-pass filter to reduce output noise. In order to maximize resolution, the 1/f noise of the transmitted signal is less than 5uVpp, and the DC offset voltage is less than 10uV. This circuit has extremely low offset voltage and is suitable for amplifying DC or low-frequency signals.