The AS3921 near field communications (NFC) analog front end (AFE) targets manufacturers of smart watches, wristbands, and other space-constrained devices, enabling them to reliably support contactless payments and ticketing. The device employs the company’s boosted NFC technology that allegedly increases the useable operating volume of an NFC reader by up to 900% when compared to conventional NFC implementations. Drawing just 12µA in normal operation, and providing a power-saving Secure Element wake-up function, the AS3921 drains far less power from the battery than NFC controller circuits, which typically draw 60µA or more. It comes in a wafer-level chip-scale package (WL-CSP) measuring 2.115 mm x 1.735 mm. A device that uses the AS3921 and has an antenna of 100 mm2 can achieve the same or a bigger operating volume as a contactless card with a conventional PLM circuit transmitting via an antenna measuring at least 2,150 mm2 in area. In some cases, the device might need no dedicated NFC antenna at all, provided its metal casing can be used in place of a normal antenna. For more specs, go to http://www.ams.com/NFC-Front-End/AS3921
ams USA Inc.