U.S. Philips Corporation

Klaus Sickert

Klaus Axer

Bernhard Czar

Dominik J Berger

A data carrier (1) which can be operated in a contact-bound mode and in a contactless mode and a circuit (2) for such a data carrier (1) has contact-bound interface means (3), contactless interface means (4), data processing means (22) and data transfer means (27) by which data received when the contact-bound mode is activated and when the contactless mode is activated can be transferred from the respective interface means (3, 4) to the data processing means (22), the data transfer means (27) being constructed to perform a logic OR function and, in conformity with this construction, when simultaneously data are received by the contact-bound interface means (3) and by the contactless interface means (4) to transfer said simultaneously received data to the data processing means (22).

Dual-mode data carrier and circuit for such a data carrier with

A circuit arrangement for generating a high DC voltage utilizes a voltage multiplier cascade which requires two alternating, non-overlapping pulse trains which are generated by a pulse generator. For given applications, for example, contactless chip cards, the supply voltage is derived from an ac voltage induced into a coil and rectified by means of a bridge rectifier. This gives rise to a voltage drop. When the pulse generator operates utilizing the supply voltage, the amplitude of the output pulses is lower, i.e. a further voltage drop occurs. Therefore, in order to overcome this limitation, the pulse generator does not derive the pulses for feeding the cascade from the rectified operating voltage, but directly from the ac voltage. This results in a higher amplitude and a better efficiency. Another feature includes the blocking of the pulse generator so that it does not represent a load to the ac voltage.

Circuit arrangement for generating a high DC voltage

For each IC and adapted circuit is accommodated on the same semiconductor substrate in order to define a specific initial state of the circuit groups, which generally consist of flip-flops. The use of the invention ensures a high constancy over a wide temperature range. Moreover, the spread in the tolerances of the circuit elements is substantially eliminated.

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Bonningstedt, Germany

Klaus Sickert