Starting and power -voltage-drop protection circuit for a contactless circuit
OwnerChristophe Moreaux, Ahmed Kari +1inventors
InventorsChristophe Moreaux, Ahmed Kari, Olivier Tardiue
Life of this patent
Estimating the term…
Abstract
A contactless integrated circuit includes a voltage generator (11, 12, 13) to produce a power supply voltage (VDD) from a received RF signal. A starting circuit for the contactless integrated circuit produces a disabling signal (POR) until the power supply voltage (VDD) reaches a first voltage threshold (VS1) The starting circuit further produces the disabling signal (POR) when the power voltage (VDD) falls below a second voltage threshold (VS2) that is lower than the first voltage threshold (VS). The starting circuit has application for use in connection with chip cards, transponders, and the like.
Claims14
A starting circuit in a contactless integrated circuit comprising a voltage generator to produce a power supply voltage from a received RF signal, the starting circuit producing a disabling signal when the power supply voltage has not reached a first voltage threshold (VS1), wherein the starting circuit also produces the disabling signal (POR) when the power voltage falls below a second voltage threshold that is lower than the first voltage threshold.
A method for generating an enable/disable control signal for a contactless integrated circuit comprising the steps of:
- monitoring a supply voltage derived from a received RF signal;
- first changing the enable/disable signal from a first state to a second state when the monitored supply voltage rises above a first threshold value;
- and
- second changing the enable/disable signal from the second state to the first state when the monitored supply voltage drops below a second threshold value;
- wherein the first threshold value exceeds the second threshold value.
A contactless integrated circuit, comprising:
- a voltage generator that produces a power supply voltage from a received RF signal;
- and
- a starting circuit that generates an enable/disable control signal responsive to changes in the power supply voltage such that the enable/disable control signal changes from a first state to a second state when the power supply voltage rises above a first threshold value, and changes from the second state to the first state when the monitored supply voltage drops below a second threshold value that is less than the first threshold value.
Dependencies are inferred from the claim text.