摘要:
A device for the bi-directional transmission of data between a master system and a slave system uses a single transmission antenna and a single reception antenna each tuned to the same frequency; the master system comprises first data transmission circuits for transmitting first data to the slave system by modulating an electromagnetic signal at the frequency; detection circuits for detecting, during the transmission of the electromagnetic signal, variations in electrical characteristics of the master system induced by a modulation of the impedance of the slave system as a function of second data to be transmitted from the slave system to the master system; and restoring circuits for restoring the second data on the basis of the detected variations; and the slave system comprises reception circuits connected to the reception antenna for restoring the first data; a rectifier circuit connected across the reception antenna for rectifying an electrical signal induced in the reception antenna by the electromagnetic signal; a power supply circuit connected to the rectifier circuit for powering the circuits and the loads of the slave system with a DC voltage on the basis of energy from the rectified electrical signal; and a switching circuit connected in series between the rectifier circuit and the power supply circuit to modulate the real part of the impedance of the slave system between a high value and a low value when the switching circuit is driven in its opened and closed position by a control signal representative of the second data.
摘要:
A circuit for the detection of address transistions in an integrated circuit comprises a logic signal input terminal, a D flip-flop for memorizing the state of the input signal, and a comparator having a first input terminal connected to the logic signal input terminal and a second input terminal connected to the output terminal of the memorizing means. The comparator gives a first logic level when its input terminals receive a same logic signal level and a second logic signal level when its input terminals receive different logic signal levels. This circuit enables the generation of an output pulse as soon as there is an input address transition, in such a way that the time delay of the output with respect to the address transition is kept to a minimum and the duration of the pulse is suitable for use in the integrated circuit which is sought to be activated.
摘要:
The present invention relates to a reenergizing circuit designed to start a MOS technology integrated circuit. It comprises a power supply terminal, a ground terminal and an output terminal, a first capacitor which is connected between the ground terminal and a circuit node; the capacitor has a charge which is controlled by means of a first p-type transistor which is connected between the power terminal and the circuit node. It further comprises an inverter gate which has a modifiable threshold voltage whose input terminal is connected to the circuit node, an inverter connected between the output terminal of the inverter gate and the output terminal, a current source which is connected in series to a divider circuit controlling the first p-type transistor and a circuit (C) having a transfer function V.sub.S =f (V.sub.E) of the inverter type, said circuit (C) being connected between the output terminal of the inverter gate and the current source in order to control the operation of the current source.
摘要:
A powering circuit to start up a MOS technology integrated circuit consists of first means made up of an oscillator and a voltage-increasing device to generate, from a supply voltage, a voltage greater than said supply voltage, and second means to measure the difference between the supply voltage and the generated voltage and to generate a powering signal when the difference reaches a given threshold.