Secure contactless smartcard ASIC with DPA protection

A secure contactless smartcard is presented. No batteries are required as d evice power is extracted from the RF field. With the exception of an induct ive loop antenna, no external components are required. The transceiver adhe res to the ISO 14443, type B specification. This system-on-a-chip integrate s the RF circuitry with a large digital circuit without benefit of external bypass capacitors. An isolation circuit is introduced that prevents coupli ng of digital noise into the receiver. A measured bit error rate of 3E-10 i s achieved. Security is also improved as the isolation circuit increases th e required time for differential power analysis (DPA) attack by a factor of 2(22). Three-pass mutual authentication is presented and an algorithm for data restoration in the event of a tear is shown. This device was fabricate d in a 0.6-mum double-poly, triple-metal CMOS process. The chip is 2.8 mm x 2.9 mm and it requires 500 uA or approximately 2.5 mW of power.