公开(公告)号：US11537834B2

公开(公告)日：2022-12-27

申请号：US17521524

申请日：2021-11-08

Applicant: STMicroelectronics (Rousset) SAS

Inventor： Olivier Rouy

IPC: G06K19/07 ,  G06K19/077 ,  G06Q20/40 ,  H01Q1/22

Abstract: A smart card includes a first circuit delivering a power supply voltage and a second circuit coupled to the first circuit by an electrical conductor and powered with the power supply voltage. A light-emitting diode has a first terminal coupled to the electrical conductor and a second terminal coupled to a first terminal of the second circuit. During a first operating phase, the first circuit delivers a first value of the power supply voltage and the second circuit applies a first voltage to the first terminal. During a second operating phase, the first circuit delivers a second value of the power supply voltage and the second circuit applies a second voltage to the first terminal.

公开(公告)号：US11803729B2

公开(公告)日：2023-10-31

申请号：US17524094

申请日：2021-11-11

Applicant: STMicroelectronics (Rousset) SAS

Inventor： Olivier Rouy

IPC: G06K19/077 ,  H05B45/50 ,  H05B45/32 ,  H05B45/3725 ,  G06K19/07

CPC classification number: G06K19/07705 ,  G06K19/0718 ,  G06K19/0723 ,  H05B45/32 ,  H05B45/3725 ,  H05B45/50

Abstract: A light-emitting diode has an anode terminal coupled to a node of application of a power supply voltage by a first transistor and a cathode terminal coupled to a node of application of a reference voltage by a second transistor. A microcontroller includes a digital-to-analog converter and a comparator, with the comparator having a first input coupled to one of the anode and cathode terminals of the diode and a second input configured to receive an output voltage of the converter. An output signal of the comparator controls one of the first and second transistors to turn off when the comparator detects an operating condition where current flow in the light-emitting diode exceeds maximum current limit (such as with the light-emitting diode operating in an exponential operating area.

公开(公告)号：US11954548B2

公开(公告)日：2024-04-09

申请号：US17520266

申请日：2021-11-05

Applicant: STMicroelectronics (Grand Ouest) SAS ,  STMicroelectronics (Rousset) SAS

Inventor： Frederic Gouabau ,  Olivier Rouy

IPC: G06K19/07 ,  G06K19/073 ,  H05B45/10

CPC classification number: G06K19/07354 ,  H05B45/10

Abstract: A connector that is configured to receive a smart card includes: a first contact configured to receive a power supply voltage and corresponding to a first (power supply) contact area of the smart card, a second contact configured to receive a reference voltage and corresponding to contact a second (reference voltage) contact area of the smart card, and a third contact corresponding to a three-state (input/output) contact area of the smart card. A first light-emitting diode having an anode coupled to the third contact and a cathode coupled to the second contact. A second light-emitting diode has a cathode coupled to the third contact and an anode coupled to the first contact. Turning on/off of the first and second light-emitting diode is controlled by the smart card through the signal at the three-state (input/output) contact area.