Differentiating ASK Demodulator for Contactless Smart Cards Supporting VHBR

Author

Hyongmin Lee ; Jisung Kim ; Dongwoo Ha ; Taehoon Kim ; Suhwan Kim

Author_Institution

Dept. of Electr. & Comput. Eng., Seoul Nat. Univ., Seoul, South Korea

Volume

62

Issue

7

fYear

2015

fDate

Jul-15

Firstpage

641

Lastpage

645

Abstract

This brief proposes an amplitude shift keying (ASK) demodulator that uses switched-capacitor differentiators to make it compliant with the very high bit rate amendment to the ISO/IEC 14443 standard for contactless smart card applications. These differentiators detect transitions in modulated ASK signals with a carrier frequency of 13.56 MHz at data rates up to 6.78 Mb/s. The demodulator has been implemented in 0.18 μm CMOS technology. The total power consumption is under 350 μW. Measured results confirm correct operation, and it is further shown that this differentiating scheme allows the modulation index to be reduced to 2.56%.

Keywords

CMOS integrated circuits; amplitude shift keying; demodulators; smart cards; switched capacitor networks; ASK demodulator; CMOS technology; VHBR; amplitude shift keying; contactless smart cards; frequency 13.56 MHz; size 0.18 mum; switched-capacitor differentiators; Amplitude shift keying; Clocks; Demodulation; Power demand; Smart cards; Switches; ASK demodulator; Amplitude shift keying (ASK) demodulator; VHBR; contactless smart card; switched-capacitor differentiator; very high bit rate (VHBR);

fLanguage

English

Journal_Title

Circuits and Systems II: Express Briefs, IEEE Transactions on

Publisher

ieee

ISSN

1549-7747

Type

jour

DOI

10.1109/TCSII.2015.2415653

Filename

7065285