Constant-current-drive LED module device

• US 8,872,434 B2
• Filed: 11/06/2009
• Issued: 10/28/2014
• Est. Priority Date: 10/26/2009
• Status: Active Grant

• Current Assignee: Airtec System Co., Ltd.
• Original Assignee: Airtec System Co., Ltd.
• Inventors: Jung, Hye Man, Ha, Seok Jin, Park, In Ki, Koo, Sang Shin, Kim, Jong Hyun
• Primary Examiner(s): Taningco, Alexander H
• Assistant Examiner(s): Bradley, Tanina
• Application Number:
  US13/502,579
• Publication Number:
  US 20120206056A1
• Time in Patent Office: 1,817 Days
• Field of Search: 315/200.R
• US Class Current: 315/200.R
• CPC Class Codes: H05B 45/37 Converter circuits
• CPC Class Codes: H05B 45/395 Linear regulators
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

A constant-current-drive LED module device includes a rectifier configured to receive and rectify an alternating current power source; a unidirectional LED module unit configured to connect to one end of the rectifier; and a constant current unit configured to connect between the unidirectional LED module unit and the other end of the rectifier to control constant current.

Claims

1. A constant-current-drive LED module device, comprising:

a rectifier receiving and rectifying an alternating current power source and including four diodes connected in a bridge configuration, the rectifier having input terminals, a first output terminal and a second output terminal;

a bidirectional LED module unit of which a first end is connected to one of the input terminals of the rectifier and a second end is connected to an alternating current power source;

a charging and discharging unit charging and discharging the alternating current power source and including a resistor-capacitor series circuit, the resistor-capacitor series circuit being connected with the bidirectional LED module unit in parallel;

a switching unit connected between the first output terminal of the rectifier and the second output terminal of the rectifier and switched by a pulsating current output of the rectifier;

a control voltage output unit detecting load current flowing in the bidirectional LED module unit and outputting a first level driving voltage and a second level driving voltage according to a magnitude of the load current; and

a constant current driver controlled by the first level driving voltage and the second level driving voltage to provide constant current.

3. The constant-current-drive LED module device of claim 1, wherein the constant current driver is any one of a field effect transistor (FET), a bipolar junction transistor (BJT), and an insulated gate bipolar transistor (IGBT).

4. The constant-current-drive LED module device of claim 1, wherein the control voltage output unit includes:

a detection resistor detecting load current flowing in the bidirectional LED module unit; and

a three terminal zener diode outputting the first level driving voltage when control voltage applied to the detection resistor is a predetermined value or less, and outputting the second level driving voltage maintaining a short state between an anode and a cathode when the control voltage exceeds the predetermined value.

5. The constant-current-drive LED module device of claim 1, wherein when an input voltage of the alternating current power source is fluctuated within a range of 10% of the rated voltage, the load current flowing in the unidirectional LED module unit is fluctuated within a range of 5 to 20%.

6. The constant-current-drive LED module device of claim 1, wherein when an input voltage of the alternating current power source is fluctuated within a range of 10%, luminous quantity of the bidirectional LED module unit is fluctuated within a range of 9 to 20%.

2. A constant-current-drive LED module device comprising:

a rectifier receiving and rectifying an alternating current power source and including four diodes connected in a bridge configuration, the rectifier having input terminals, a first output terminal and a second output terminal;

a bidirectional LED module unit of which a first end is connected to one of the input terminals of the rectifier and a second end is connected to an alternating current power source;

a charging and discharging unit charging and discharging the alternating current power source and including a resistor-capacitor series circuit, the resistor-capacitor series circuit being connected with the bidirectional LED module unit in parallel;

a control voltage output unit detecting load current flowing in the bidirectional LED module unit and a first level driving voltage and a second level driving voltage according to a magnitude in the load current; and

a constant current driver controlled by the first driving voltage and the second driving voltage to provide the constant current.