JPH0191352U - - Google Patents

Description

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a write/read control unit of an article identification system according to an embodiment of the data communication device of the present invention, FIG. 2 is a block diagram showing its overall configuration, and FIG. 3 is an ID unit. FIG. 4 is a time chart showing the waveforms of each part when data is transmitted from the write/read control unit to the ID unit, and FIG. This is a time chart showing the waveforms of each part when transmitting. 1...Write/read control unit, 3...ID unit, 4...Control equipment, L1, L2, L3...
Coil, 11...Clock generator, 12...Time controller, 13...Transmission pulse generation circuit,
14... Reception gate signal generation circuit, 15... Oscillator, 17, 30... Resonance circuit, 18, 21... Analog switch, 22, 31... Detection circuit, 25
... Sample and hold circuit, 26, 32 ... Comparator, 27 ... Resonance control means, 33 ... Counter,
34...Digital comparator, 36...Memory control unit, 37...Memory, 38...Residual control pulse generator, 41...Battery, 42...Data demodulation means, 43...Reverberation control means.

Claims (1)

[Claims for Utility Model Registration] A data communication device that performs half-duplex data transmission of serial data between a first unit and a second unit, wherein the first unit is opposite to the second unit. an oscillator having a first coil provided on a surface that transmits data; a transmission pulse generating means that generates a transmission pulse signal with a certain period and intermittents the oscillation by providing the transmission pulse signal with a certain period to the oscillator; a first resonant circuit including a second coil provided on a surface facing the second unit; and a first resonant circuit including a second coil provided on a surface facing the second unit; a receiving gate signal generating means for generating a receiving gate signal having timing, and a series connection body of an analog switch and a resistor that are provided in parallel with the first resonant circuit and are switched on and off by the receiving gate signal, resonance control means for controlling the Q of the first resonant circuit; a detection circuit for detecting an electromagnetic induction signal obtained in the first resonant circuit while a reception gate signal of the reception gate signal generation means is applied; a sample hold circuit that samples the output of the detection circuit at a predetermined timing of the reception gate signal; and a first comparator that discriminates the hold signal of the sample hold circuit at a predetermined level; a second resonant circuit including a third coil having a resonant frequency substantially equal to the oscillation frequency of an oscillator of the first unit and provided on a surface facing the first unit; a detection circuit that detects a signal obtained in the second resonant circuit; a second comparator that obtains a transmission pulse signal by discriminating the detection output at a predetermined threshold level; data demodulation means for demodulating the transmitted data signal from the transmitted pulse signals of the first and second duty ratios based on the output of the second comparator when receiving the data; and connected between the second resonant circuit and ground. The switching element is configured to switch the oscillator at the timing of stopping oscillation of the oscillator based on a transmission pulse signal of a third duty ratio obtained from the second comparator during data transmission to the first unit. 1. A data communication device comprising: reverberation control means for controlling reverberation occurring in the second resonant circuit by intermittent transmission in accordance with transmitted data.