Nxp B.v.

Olivier Susplugas

Stefano Dal Toso

Melaine Philip

Olivier Jérôme Célestin Jamin

Olivier Frédéric Guttin

It is described a signal converter device () for converting a single-ended signal to a differential signal, the device () comprising: Further, a corresponding signal conversion method is described.

Single-ended to differential signal converter, and signal converting method

Disclosed is a card clock recovery system for use in an NFC card transceiver couplable to an NFC reader. The card clock recovery system has: a phase lock loop having: a phase/frequency detector, which is configured to receive a reference signal provided at an RX port of a matching network during a receiving mode of the NFC transceiver or to receive a reference signal provided at the RX port of the matching network during a transmission mode of the NFC transceiver, to receive a loop feedback signal, and to provide a phase error signal that represents a phase difference between the reference signal and the loop feedback signal; a loop filter configured to receive a corrected phase error signal that is derived from the phase error signal, and to provide a filtered corrected phase error signal; a controllable oscillator, which is configured to receive the filtered corrected phase error signal and to provide a controlled frequency output signal, which is provided as the card clock generation control signal to a card clock generation unit of an NFC card transceiver, and as the loop feedback signal, via the loop feedback line, to the phase/frequency detector. The card clock recovery system further has a phase offset correction unit, which is configured to receive the phase error signal provided by the phase/frequency detector and to provide the corrected phase error signal to the loop filter, and which has a phase error sampling unit, a phase offset computation unit, and a phase subtractor unit.

System and method of clock recovery with low phase-error for card emulation clock-less NFC transceivers

A RF transceiver for RF communication with a further RF transceiver is described. The RF transceiver comprises a RF transmitter; a clock generator coupled to the RF transmitter, the clock generator comprising a crystal oscillator circuit including an amplifier, a distance monitor configured to monitor the distance between the RF transceiver and the further RF transceiver; a controller coupled to the distance monitor and the clock generator. The controller is configured to vary the crystal oscillator swing amplitude dependent on the distance between the RF transceiver and the further RF transceiver.

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Caen, France

Olivier Susplugas