Rectifier circuit and vision regeneration assisting apparatus having the same

• US 7,242,597 B2
• Filed: 07/29/2005
• Issued: 07/10/2007
• Est. Priority Date: 08/04/2004
• Status: Expired due to Fees

• Current Assignee: Nidek Company Limited
• Original Assignee: Nidek Company Limited
• Inventors: Shodo, Kenzo
• Primary Examiner(s): HAN, YOUNGHUIE JESSICA
• Application Number:
  US11/192,429
• Publication Number:
  US 20060064141A1
• Time in Patent Office: 711 Days
• Field of Search: 363/89, 363/125, 363/127, 323/911, 602/2, 602/54
• US Class Current: 363/127
• CPC Class Codes: A61N 1/36046 of the eye
• CPC Class Codes: H02M 7/217 using semiconductor devices only
• CPC Class Codes: Y10S 323/911 Medical electronics

Abstract

A rectifier circuit for converting an AC voltage to a DC voltage has a first MOS transistor having a source connected to a first input terminal of an AC power supply, and also having a drain connected to an output terminal thereof, a first parasitic diode formed between the first input terminal and the output terminal, a first detection circuit, connected to the first input terminal and to the output terminal, for detecting a difference in voltage between the first input terminal and to the output terminal, a second MOS transistor, adapted to be reverse in polarity to the first MOS transistor, having a source connected to a second input terminal of the AC power supply and also having a drain connected to a ground terminal, a second parasitic diode formed between the input terminal and the ground terminal, a second detection circuit, connected to the second input terminal and the ground terminal, for detecting a difference in voltage between the second input terminal and the ground terminal, and a capacitor connected to the output terminal and the ground terminal. The first detection circuit turns on/off the first MOS transistor according to the difference in voltage, which is detected by the first detection circuit. The second detection circuit turns on/off the second MOS transistor according to the difference in voltage, which is detected by the second detection circuit.

Claims

1. A rectifier circuit for converting AC voltage to DC voltage, comprising:

a first MOS transistor having a source connected to a first input terminal of an AC power supply and a drain connected to an output terminal;

a first parasitic diode formed between the first input terminal and the output terminal;

a first detection circuit, connected to the first input terminal and to the output terminal, for detecting a difference in voltage between the first input terminal and the output terminal;

a second MOS transistor having a source connected to a second input terminal of the AC power supply and a drain connected to a ground terminal, the second MOS transistor having polarity opposite to the first MOS transistor;

a second parasitic diode formed between the input terminal and the ground terminal;

a second detection circuit, connected to the second input terminal and the ground terminal, for detecting a difference in voltage between the second input terminal and the ground terminal; and

a capacitor connected to the output terminal and the ground terminal,

wherein the first detection circuit turns on/off the first MOS transistor according to the difference in voltage detected by the first detection circuit, and

wherein the second detection circuit turns on/off the second MOS transistor according to the difference in voltage detected by the second detection circuit.

2. The rectifier circuit according to claim 1, wherein the first detection circuit and the second detection circuit include MOS transistors, respectively.

3. The rectifier circuit according to claim 2, wherein

the first MOS transistor and the MOS transistor of the first detection circuit include P-MOS transistors, and

the second MOS transistor and the MOS transistor of the second detection circuit include N-MOS transistors.

4. The rectifier circuit according to claim 3, wherein all components thereof other than the capacitor are formed in a monolithic structure.

5. A vision regeneration assisting apparatus having the rectifier circuit according to claim 1, comprising:

an electric power acquisition unit which obtains necessary electric power by electromagnetic induction; and

an electrical stimulation unit which has a plurality of electrodes and outputs an electrical stimulation pulse signal to cells constituting a retina of a patient'"'"'s eye by using the DC voltage converted by the rectifier circuit from an AC voltage obtained by the electric power acquisition unit.