Samsung Electronics Co., Ltd.

Sanghyo Lee

Kyeongdo Kim

Seungwon Lee

Jongpil Cho

Youngseok Kim

Inhyuk Kim

Minhyeok Kang

Minchul Kang

The present disclosure provides systems and devices including reception circuits for communications between smart cards and card readers. In some embodiments, a reception circuit of a smart card includes a first circuit and a second circuit. The first circuit is configured to receive a wireless signal including a pause, and restore the wireless signal to a clock signal. The second circuit is configured to charge a voltage of a first node based on a first logic level of the clock signal, compare the voltage of the first node with a predefined reference voltage, and output, based on the comparison of the voltage of the first node, a synchronization signal indicating a rising starting time point of the pause of the wireless signal.

Reception circuit and smart card including the same

A communication device is provided. The communication device includes: an antenna; a matching circuit connected with the antenna; a transmitter configured to generate a transmission communication signal and provide the transmission communication signal to the antenna through the matching circuit; a filter connected between the matching circuit and the antenna; and a receiver configured to receive an attenuated signal from the antenna through the filter. The filter is configured to pass frequencies of an antenna signal corresponding to a pass band and attenuate frequencies of the antenna signal corresponding to a stop band, and a center frequency of the transmission communication signal corresponds to the stop band of the filter.

Communication device, electronic device including communication device, and operating method of electronic device

A smart card includes an antenna to transmit and to receive a radio frequency signal, a rectifier to rectify a signal received through the antenna to output a rectified voltage, a voltage regulator to operate in a first operation mode for stabilizing a level of the rectified voltage and a second operation mode for generating an internal voltage using the rectified voltage, a regulator converter to control the voltage regulator to operate the voltage regulator in one of the first operation and the second operation according to a mode selection signal, a clamp circuit to connect an output terminal of the rectifier to a ground according to the mode selection signal, a load modulator to vary a resistance of the antenna to perform a load modulation, and a regulator controller to generate the mode selection signal according to whether the load modulator is activated or deactivated.

Mode-changeable power supply circuit and smart card including the same

A near field communication (NFC) device includes a resonator including an antenna and a matching circuit, a transmitter and a frequency detector. The transmitter generates a sensing voltage signal at the resonator. With respect to a plurality of measurement periods where each measurement period includes a turn-on period and a turn-off period, the transmitter is enabled to output a radio frequency (RF) signal to the resonator during the turn-on period and disabled during the turn-off period. The frequency detector detects a resonance frequency of the resonator based on the sensing voltage signal. The resonance frequency is accurately detected by measuring the resonance frequency during the plurality of measurement periods. In addition, the resonance frequency is efficiently detected by generating the sensing voltage signal using the transmitter established in the NFC device.

Growing community of inventors

Incheon, South Korea

Sanghyo Lee