The temperature sensor is directly connected to the microcontroller
China's leading supplier of signal chain chips and solutions, Suzhou Naxin Microelectronics Co., Ltd. announced the introduction of high-precision dual-pin digital output temperature sensor chip NST1001. NST1001 has the characteristics of pulse counting digital output and high precision in wide temperature range. It can be directly connected with MCU to ensure measurement accuracy and reduce the cost of MCU design. The temperature measurement range of NST1001 is from - 50 C to 150 C, which meets the temperature requirements of cold chain transportation, grain monitoring, household appliances, industrial Internet of Things and other occasions. Compared with traditional NTC thermistors, NST1001 has simpler, more accurate and more stable characteristics. Its maximum error in the temperature range from - 20 C to 85 C is 0.5 C, and the maximum error in the whole temperature range is 0.75 C. Its resolution can reach 0.0625 C. In addition, NST1001 provides a high-resolution version of NST1001_H, ranging from - 20 C to 80 C, and achieves a very high resolution of 0.03125 C.
The traditional NTC thermistor has the advantages of low cost, simple connection and easy to make temperature probe. It is widely used in consumer electronics, household appliances, industry and Internet of Things. However, NTC thermistors usually have great nonlinearity, which can guarantee a certain accuracy only in a very narrow temperature range, and the measurement accuracy in a slightly larger temperature range will be greatly reduced. In addition, in order to convert resistance value into temperature value, the system needs to match a high-precision reference resistance. At the same time, MCU microcontroller needs to provide an ADC with more than 12 bits, and use the look-up table to calculate the temperature value of resistance, which increases the cost of the system and the complexity of operation. In view of the above factors, it is a preferred choice for developers to replace the traditional NTC thermistor with a high precision, low cost and easy operation temperature sensor scheme.
The low power digital output temperature sensor chip NST1001 introduced by nano-core microelectronics has only two pins, GND and DQ, which can directly replace the traditional NTC resistance without changing the peripheral circuit. When the chip works, when DQ is connected by a pull-up resistor, the pulse signal will be sent out periodically on the DQ pin. MCU/MCU can directly get the temperature reading by counting the pulse signal through a GPIO, which greatly simplifies the hardware facilities of the circuit. Each NST1001 chip has been calibrated before it is manufactured. The error is (+0.5 degree C) at - 20 C ~ 85 C, within - 50 C ~ - 20 C (+0.75 degree C), and (+0.75 degree C) at 85 150 C. NST1001 can adapt to the wide operating voltage range of 1.65V~5.5V. The current is only 30uA at temperature conversion and 1uA at pulse output, with almost no self-heating effect. When GPIO is used to supply power to pull-up resistor, zero standby power consumption can be achieved. These characteristics make NST1001 very suitable for temperature monitoring of low-power Internet of Things nodes, such as cold chain transportation, food monitoring, industrial Internet of Things and so on.
NST1001 provides two packaging forms, TO-92S and DFN2L, which meet the RoHS standard. The TO-92S is especially suitable for two-wire digital temperature probe.