Energy harvesting offers a great opportunity to decrease a product footprint in standard wireless charging, extended battery lifetimes, and fully passive wireless solutions. While some in-home devices already utilize energy harvesting sensors, they aren’t readily available, often generate a small amount of power, and are expensive.
Where Energy Harvesting Makes a Difference
Although there are a variety of applications for sensors that are capable of energy harvesting, there are a few industries that stand to benefit even more. Biometric smart cards, for example, offer a limited surface area, making the need for a limited footprint even more important. In smart insulin pens, where there is a need for no added costs or chemicals, energy harvesting capabilities offer a solution that allows for fair pricing and effective results. In fact, throughout the medical industry, the need for energy harvesting sensors is increasing, especially in implantables.
Block diagram for the AS3956. Image courtesy of ams.
The ams Solution
Advanced sensor solutions designer and manufacturer ams recently introduced an NFC sensor tag IC for industrial IoT applications exposed to harsh operating conditions, including extreme temperatures, extended operating lifetime, and a need for wireless sensors. The AS3956 meets industrial-grade standards and provides reliability, acting as a contactless bridge between sensors and any NFC reader, including devices like a smartphone via a host microcontroller.
The AS3956 is capable of energy-harvesting, drawing energy from the incoming RF field generated by an NFC reader. It supplies up to 5mA to an external device and is available in a miniature chip-scale package, available for sampling now at $0.53 in an order quantity of 1,000 units.
ams claims that, in designing the AS3956, they drew on interaction with customers that manufacture products for industrial applications and IoT, validating performance and reliability in real-world situations that would simulate demanding operating conditions. AS3956 differs from the competition because of the ability to operate in temperatures ranging from 40 degrees Celsius to 125 degrees Celsius. They promote it as an ideal solution for HVAC equipment, hearing aids, and wireless sensors for infrastructure, including roads, bridges, and utilities.
According to ams, the AS3956’s internal EEPROM memory is rated for a minimum 100,000 program/erase cycles with 10 years’ data retention at 125 degrees Celsius, offering flexibility in implementing NFC-based applications, including the provision of different interfaces to host a microcontroller and a wide supply voltage range.
The AS3956 acts as a stand-alone Type 2 tag, which conforms to the NFC Forum standards and supports NFC communication. Each two data-transfer model for a host controller communication can be selected, including an extended mode with a self-timed data transfer mechanism and a tunneling mode to implement ISO14443A Level 4 PICC emulation in line with EMVCo requirements or custom protocols.