Dual mode regulated light-emitting diode module for flashlights

• US 6,791,283 B2
• Filed: 09/06/2002
• Issued: 09/14/2004
• Est. Priority Date: 09/07/2001
• Status: Expired due to Fees

• Current Assignee: Opalec
• Original Assignee: Opalec
• Inventors: Post, Stephen F., Bowman, Scott A.
• Primary Examiner(s): VO, TUYET THI
• Application Number:
  US10/309,408
• Publication Number:
  US 20030076051A1
• Time in Patent Office: 739 Days
• Field of Search: 315/291, 315/307, 315/297, 315/200.A, 315/312, 315/324, 315/56, 315/58, 315/224, 361/84, 361/86, 361/87, 362/10, 362/800
• US Class Current: 315/291
• CPC Class Codes: H05B 45/3574 Emulating the electrical or functional characteristics of incandescent lamps
• CPC Class Codes: H05B 45/38 using boost topology
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

An LED illumination module for a flashlight has a housing, electronic control circuitry, and one or more LEDs connected in series and to the circuitry. The module is characterized in that the module is shaped to modularly replace an incandescent-bulb in an existing flashlight. In one aspect the control circuitry operates in a dual mode to extend life of the unit, and to warn when battery replacement is warranted.

Claims

1. An LED illumination module for a flashlight, comprising:

a housing;

electronic control circuitry; and

one or more LEDs connected in series and to the circuitry;

wherein the electronic control circuitry provides two distinct operating modes, a first mode substantially stabilizing current through the LEDs as battery voltage wanes, and a second mode active below a preset battery voltage to substantially stabilize battery voltage while allowing current to the LEDs to decrease, also allowing light intensity to decrease as well.

2. The LED module of claim 1 wherein activation of the second mode also triggers a low-battery alert.

3. The LED module of claim 2 wherein the low-battery alert comprises a colored LED.

4. The LED module of claim 2 wherein the low-battery alert comprises an audio element.

5. The LED module of claim 2 wherein the low-battery alert comprises intensity modulation of one or more of the LEDs.

6. An LED illumination module for a flashlight, comprising:

a housing;

electronic control circuitry; and

one or more LEDs connected in series and to the circuitry;

wherein the electronic control circuitry includes reverse polarity protection circuitry having a MOSFET blocking flow of current of reverse polarity, and conducting current of correct polarity, said MOSFET being turned on by a voltage higher than that of the battery provided by a DC/DC voltage boost converter.

7. An LED illumination device, comprising:

electronic control circuitry; and

one or more LEDs connected in series and to the circuitry;

wherein the electronic control circuitry provides two distinct operating modes, a first mode substantially stabilizing current through the LEDs as battery voltage wanes, and a second mode active below a preset battery voltage to substantially stabilize battery voltage while allowing current to the LEDs to decrease, also allowing light intensity to decrease as well.

8. The LED illumination device of claim 7 wherein activation of the second mode also triggers a low-battery alert.

9. The LED illumination device of claim 8 wherein the low-battery alert comprises a colored LED.

10. The LED illumination device of claim 8 wherein the low-battery alert comprises an audio element.

11. The LED illumination device of claim 8 wherein the low-battery alert comprises intensity modulation of one or more of the LEDs.

12. An LED illumination device, comprising:

a housing;

electronic control circuitry; and

one or more LEDs connected in series and to the circuitry;

wherein the electronic control circuitry includes reverse polarity protection circuitry having a MOSFET blocking flow of current of reverse polarity, and conducting current of correct polarity, said MOSFET being turned on by a voltage higher than that of the battery provided by a DC/DC voltage boost converter.