This design is ideal for applications that require accurate temperature monitoring, particularly for human skin, and allows the transfer of temperature data to an NFC receiver, such as an NFC-enabled smartphone.
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The Passive NFC Temperature Patch represents a significant advancement in wearable health technology, offering a seamless and efficient way to monitor body temperature continuously. Unlike traditional thermometers, this innovative patch utilizes Near Field Communication (NFC) technology to transmit temperature data to compatible devices without the need for batteries. Its lightweight, flexible design ensures comfort and ease of use, making it ideal for both clinical settings and everyday personal health monitoring. With its ability to provide real-time temperature tracking and its integration with smart health applications, the Passive NFC Temperature Patch is set to revolutionize how we manage and understand our health.
The TIDA-00721 by Texas Instruments is Passive NFC Temperature Patch Reference Design provides an advanced solution for precise temperature measurement using a passive NFC tag in a flexible patch form factor. This system is constructed with several key components to ensure high accuracy and reliable performance. Central to the system is the LMT70, a high-accuracy analog temperature sensor renowned for its precise temperature readings. This sensor effectively captures the local temperature, providing the necessary data for accurate monitoring.
The temperature data collected by the LMT70 is then converted from analog to digital using the ADS1113, a 16-bit Sigma-Delta analog-to-digital converter (ADC). This ADC ensures that the temperature signals are digitized with high resolution and accuracy, maintaining the integrity of the data. Once digitized, the temperature data is managed by the MSP430G2403 microcontroller. This low-power mixed-signal microcontroller is responsible for storing the digitized data and preparing it for transmission. The microcontroller plays a crucial role in ensuring that the data is handled efficiently and accurately.
The stored temperature data is then transmitted via the RF430CL330H, a dynamic NFC interface transponder. This component packages the data into the NFC protocol, ensuring seamless data transfer to an NFC-enabled reader, such as a smartphone. This step is critical for the reliable communication of temperature data between the patch and the receiver. An integrated PCB antenna is included in the design to facilitate NFC communication, making the patch easy to use and implement. Additionally, probe contacts are incorporated for programming or troubleshooting purposes, adding to the design’s flexibility and utility in various applications.
This design is highly versatile and finds applications across a wide range of industries. In the industrial sector, it is well-suited for devices such as blood glucose monitors, CPAP machines, CT detector modules, continuous glucose monitor aggregators, ECG patches, and more. These applications benefit from the design’s ability to ensure accurate temperature readings for calibration, functionality, and patient monitoring. In personal electronics, the design is particularly useful for smart trackers, enhancing the accuracy of activity and fitness monitoring by incorporating precise temperature measurements. This makes it a valuable tool for consumers looking to monitor their health and fitness more accurately.
The Reference Design stands out for its accuracy, integration, and ease of use. By leveraging the capabilities of the LMT70 temperature sensor, ADS1113 ADC, MSP430G2403 microcontroller, and RF430CL330H NFC transponder, this reference design ensures reliable and accurate temperature data transmission through a simple yet effective NFC interface. This makes it an invaluable tool in both industrial and personal electronics applications, providing a sophisticated solution for precise temperature monitoring.
TI has tested this reference design. It comes with a bill of materials (BOM), schematics, etc. You can find additional data about the reference design on the company’s website. To read more about this reference design, click here.