Patent ID: 6145749
Filing Date: 2000-11-14
Classification: G06K

Abstract:
A data carrier (1) which can be operated in a contact-bound mode and in a contactless mode and which includes the means specified hereinafter, namelya transmission contact (17) and a further transmission contact (19) which are both mechanically accessible from outside the data carrier (1), andat least one transmission coil (31) which is inductively accessible from outside the data carrier (1) and which serves to receive a useful HF signal (HF) in the contactless mode of the data carrier (1), anda circuit (1A) which has a contact terminal (17A) connected to the one transmission contact (17) and which has a further contact terminal (19A) connected to the further transmission contact (19) and which includes supply voltage generating means (35) to which a received useful HF signal (HF) can be applied and by which a supply voltage (VDD) for various circuit sections of the circuit (1A) of the data carrier (1) can be derived from an applied useful HF signal (HF),characterized in thatthe circuit (1A) includes potential equalizing means (94) by which the contact terminal (17A) connected to the one transmission contact (17) and the further contact terminal (19) connected to the further transmission contact (19) can be brought at substantially the same potential (ground) when a sufficiently powerful useful HF signal (HF) is received, from which a supply voltage (VDD) can be derived by the supply voltage generating means (35).