Semiconductor Device

• US 20110163613A1
• Filed: 03/14/2011
• Published: 07/07/2011
• Est. Priority Date: 10/18/2006
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Tadokoro, Asami, Kato, Kiyoshi
• Granted Patent: US 8,977,203 B2
• Time in Patent Office: Days
• US Class Current: 307/130
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• CPC Class Codes: G06K 19/0715 the arrangement including means to regulate power transfer to the integrated circuit
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: H01Q 1/2208 associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems methods or arrangements for sensing record carriers, e.g. for reading patterns G06K7/00; record carrier for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: H01Q 1/2283 mounted in or on the surface of a semiconductor substrate as a chip-type antenna or integrated with other components into an IC package
• CPC Class Codes: H02H 9/02 responsive to excess current current limitation for voltage regulators G05F1/573; disconnection after limiting H02H3/025

Abstract

Of a wireless communication system, an RF tag which can operate normally even when a communication distance is extremely short, like the case where the RF tag is in contact with a reader/writer, whereby the reliability is improved. The RF tag which communicates data by wireless communication includes a comparison circuit which compares electric power supplied from outside with reference electric power and a protection circuit portion which is operated when the electric power supplied from outside is higher than the reference electric power in the comparison circuit.

Claims

1-21. -21. (canceled)

22. A semiconductor device comprising:

a protection circuit comprising a switch; and

a resistor and a diode connected in series between a first terminal and a second terminal of the protection circuit;

wherein the switch is configured to be controlled according to an electric potential of a node between the resistor and the diode.

24. A semiconductor device according to claim 22, further comprising a load electrically connected in series with the switch between the first terminal and the second terminal of the protection circuit.

26. The semiconductor device according to claim 24, wherein the load comprises at least one of a capacitor, a second resistor, and an inductor.

28. The semiconductor device according to claim 22,

wherein the switch is a transistor;

and

wherein a gate of the transistor is configured to be supplied with an electric potential in accordance with an electric potential of the node between the resistor and the diode.

30. A semiconductor device according to claim 28, further comprising a capacitor electrically connected between the gate of the transistor and one of the first terminal and the second terminal of the protection circuit.

32. An RF tag comprising a semiconductor device according to claim 22.

23. A semiconductor device comprising:

an antenna;

a rectifier circuit electrically connected to a first terminal and a second terminal of the antenna;

a protection circuit comprising a switch and electrically connected to the first terminal and to the second terminal of the antenna; and

a resistor and a diode connected in series between the first terminal and the second terminal of the antenna;

wherein the switch is configured to be controlled according to an electric potential of a node between the resistor and the diode.

25. A semiconductor device according to claim 23, further comprising a load electrically connected in series with the switch between the first terminal and the second terminal of the antenna.

27. The semiconductor device according to claim 25, wherein the load comprises at least one of a capacitor, a second resistor, and an inductor.

29. The semiconductor device according to claim 23,

wherein the switch is a transistor;

and

wherein a gate of the transistor is configured to be supplied with an electric potential in accordance with an electric potential of the node between the resistor and the diode.

31. A semiconductor device according to claim 29, further comprising a capacitor electrically connected between the gate of the transistor and one of the first terminal and the second terminal of the antenna.

33. An RF tag comprising a semiconductor device according to claim 23.

34. A semiconductor device comprising:

a protection circuit comprising a switch;

a comparison circuit configured to compare a voltage supplied by a rectifier circuit with a reference voltage and comprising;

a diode, an anode of the diode being electrically connected to a node p, the node p being electrically connected to a first terminal of the comparison circuit and a cathode of the diode being electrically connected to a second terminal of the comparison circuit;

a first transistor, a gate of the first transistor being electrically connected to the node p, and one of a source and a drain of the first transistor being electrically connected to the first terminal of the comparison circuit;

a second transistor, one of a source and a drain of the second transistor being electrically connected to the other of the source and the drain of the first transistor at a node q, and the other of the source and the drain of the second transistor being electrically connected to the second terminal of the comparison circuit;

wherein the gate of the second transistor is configured to be set at the reference voltage; and

wherein the switch of the protection circuit is configured to control a passage of current in the protection circuit according to an electric potential of the node q.

35. A semiconductor device according to claim 34, further comprising a load electrically connected in series with the switch between the first terminal of the comparison circuit and the second terminal of the comparison circuit.

36. A semiconductor device according to claim 34,

wherein the switch is a third transistor;

and

wherein the gate of the third transistor is electrically connected to the node q.

37. A semiconductor device according to claim 34, further comprising a resistor electrically connected between the node p and the first terminal of the comparison circuit.

38. A semiconductor device according to claim 34, further comprising a capacitor electrically connected between the node q and the second terminal of the comparison circuit.

39. A semiconductor device according to claim 34, further comprising a constant voltage source circuit, an output of the constant voltage source circuit being electrically connected to the gate of the second transistor.

40. A semiconductor device according to claim 34, further comprising a charging mechanism control portion and a battery electrically connected thereto, an output of the charging mechanism control portion being electrically connected to the gate of the second transistor.

41. An RF tag comprising a semiconductor device according to claim 34.