Ultra-Low Power Current-Mode ASK Demodulator for Contactless Smart Cards

A fully CMOS current-mode ASK demodulator for contactless smart cards is proposed. The power consumption of the ASK demodulator has been reduced to
$7\mu\mathrm{W}$
utilizing a dc-current removal technique. Due to this technique, only the ac component of the envelope signal is amplified by the current amplifier to drastically reduce power consumption. The results reveal a modulation index of 5% with a data rate of 800kbps is supported by the ASK demodulator.