Energy-saving dimming apparatus

• US 6,858,995 B2
• Filed: 03/18/2003
• Issued: 02/22/2005
• Est. Priority Date: 03/18/2002
• Status: Expired due to Fees

• Current Assignee: Kyoung-Hwa Yoon, Weon-Ho Lee
• Original Assignee: Kyoung-Hwa Yoon, Weon-Ho Lee
• Inventors: Yoon, Kyoung-Hwa, Jung, Dong-Youl, Park, Chong-Yeun, Lee, Weon-Ho
• Primary Examiner(s): Vo, Tuyet Thi
• Application Number:
  US10/391,334
• Publication Number:
  US 20030173906A1
• Time in Patent Office: 707 Days
• Field of Search: 315/224, 315/307, 315/225, 315/291, 315/209.R, 315/DIG.4, 315/200.R, 315213-218, 315/276, 315/279
• US Class Current: 315/224
• CPC Class Codes: H05B 41/3924 by phase control, e.g. using a triac H05B41/3922 takes precedence
• CPC Class Codes: Y10S 315/04 Dimming circuit for fluorescent lamps

Abstract

Disclosed is an energy-saving dimming apparatus connected to a power source and a load, and adapted to control a luminance of the load. The dimming apparatus includes a first switching unit connected to a power supply line, a second switching unit connected between the first switching unit and a ground line, a microprocessor for generating a square-wave pulse having a duty cycle according to a luminance control command, a switch driver for generating switching control signals respectively adapted to perform alternate ON/OFF controls for the switching units in accordance with the square-wave pulse inputted thereto, and a low-pass filter for removing ripple components contained in a voltage applied to the load via the first switching unit.

Claims

1. An energy-saving dimming apparatus connected to a power source and a load, and adapted to control a luminance of the load, comprising:

a first switching unit connected to a power supply line;

a second switching unit connected between the first switching unit and a ground line;

a microprocessor for generating a square-wave pulse having a duty cycle according to a luminance control command;

a switch driver for generating switching control signals respectively adapted to perform alternate ON/OFF controls for the switching units in accordance with the square-wave pulse inputted thereto;

a low-pass filter for removing ripple components contained in a voltage applied to the load via the first switching unit; and

a level amplifier for amplifying a level of the square-wave pulse.

2. The energy-saving dimming apparatus according to claim 1, wherein each of the first and second switching units is a field effect transistor adapted to be switched on/off in accordance with an associated one of the switching control signals applied to a gate thereof.

3. The energy-saving dimming apparatus according to claim 1, wherein the low-pass filter is an LC filter.

4. The energy-saving dimming apparatus according to claim 1, further comprising:

an electromagnetic interference filter for removing harmonic components of a current supplied via the power supply line, and removing electromagnetic interference.

5. The energy-saving dimming apparatus according to claim 4, wherein each of the first and second switching units comprises two field effect transistors connected to the power supply line at respective drains thereof, and connected to each other at respective sources thereof, the field effect transistors receiving the switching control signals at the drains thereof, respectively.

6. The energy-saving dimming apparatus according to claim 4, wherein each of the first and second switching units is a field effect transistor adapted to be switched on/off in accordance with an associated one of the switching control signals applied to a gate thereof.

7. The energy-saving dimming apparatus according to claim 4, wherein the low-pass filter is an LC filter.

8. The energy-saving dimming apparatus according to claim 1, wherein each of the first and second switching units comprises two field effect transistors connected to the power supply line at respective drains thereof;

and connected to each other at respective sources thereof, the field effect transistors receiving the switching control signals at the drains thereof, respectively.

9. The energy-saving dimming apparatus according to claim 8, wherein the switch driver comprises:

a switch driving IC for outputting, at two ports, switching control signals having different logic levels in accordance with a logic level of the square-wave pulse inputted thereto, respectively; and

two transformers for transferring the switching control signals outputted from the switch driving IC to the gates of the field effect transistors, respectively.

10. The energy-saving dimming apparatus according to claim 9, wherein the switch driver further comprises:

a capacitor provided at a secondary winding of each of the transformers, and adapted to amplify a voltage induced at the secondary winding of the transformer; and

a resistor provided at the secondary winding of the transformer, and adapted to discharge a parasitic capacitor of an associated one of the field effect transistors.

11. The energy-saving dimming apparatus according to claim 8, wherein the switch driver comprises:

a first switch driving IC for outputting a switching control signal having the same logic level as that of the square-wave pulse inputted thereto;

a first transformer for transferring the switching control signal outputted from the first switch driving IC to the gate in the first switching unit;

a second switch driving IC for outputting a switching control signal having a logic level inverse to that of the square-wave pulse inputted thereto; and

a second transformer for transferring the switching control signal outputted from the second switch driving IC to the gate in the second switching unit.

12. The energy-saving dimming apparatus according to claim 11, wherein the switch driver further comprises:

a capacitor provided at a secondary winding of each of the transformers, and adapted to amplify a voltage induced at the secondary winding of the transformer; and

a resistor provided at the secondary winding of the transformer, and adapted to discharge a parasitic capacitor of an associated one of the field effect transistors.

13. A dimming apparatus comprising:

an electromagnetic interference filter for removing harmonic components of a current inputted via a power supply line, and removing electromagnetic interference;

a first switching unit connected to an output terminal of the electromagnetic interference filter;

a second switching unit connected between an output terminal of the first switching unit and a ground line;

a user interface for inputting a luminance control command;

a microprocessor for generating a square-wave pulse having a duty cycle according to the luminance control command;

a level amplifier for amplifying a level of the square-wave pulse;

a switch driver for generating switching control signals respectively adapted to perform alternate ON/OFF controls for the switching units in accordance with the square-wave pulse inputted thereto; and

a low-pass filter for removing ripple components contained in a voltage applied to the load via the first switching unit.

14. The dimming apparatus according to claim 13, wherein the user interface comprises:

a remote receiver for receiving a signal transmitted from a remote controller; and

a variable resistor having a resistance variable in accordance with a manual operation.