END-OF LIFE CIRCUITRY

• US 20110210669A1
• Filed: 09/08/2009
• Published: 09/01/2011
• Est. Priority Date: 09/11/2008
• Status: Active Grant

• Current Assignee: Switch Bulb Company, Inc.
• Original Assignee: Switch Bulb Company, Inc.
• Inventors: Thorman, Ethan, Lenk, Carol, Lenk, Ronald J.
• Granted Patent: US 9,107,273 B2
• Time in Patent Office: Days
• US Class Current: 315/119
• CPC Class Codes: H05B 45/58 involving end of life detection of LEDs

Abstract

An LED light bulb which turns itself permanently off when it reaches the end of its useful life, and more particularly, to a scheme which slightly varies the end-of-life condition from unit to unit.

Claims

1. An end-of-life detecting LED light bulb comprising:

an LED light bulb; and

a microcontroller having a circuit for detecting operational time of the bulb; and

wherein the microcontroller turns the bulb off upon reaching a preset amount of operational time.

2. An end-of-life LED light bulb as set forth in claim 1, wherein the microcontroller counts AC line cycles.

3. An end-of-life LED light bulb as set forth in claim 1, wherein the microcontroller includes a non-volatile memory.

4. An end-of-life LED light bulb as set forth in claim 3, wherein the non-volatile memory is read from at bulb power-up and written to at bulb power-down.

5. An end-of-life LED light bulb as set forth in claim 1, wherein the circuit for turning off the bulb compares the output of the circuit with a reference value.

6. An end-of-life LED light bulb as set forth in claim 2, wherein the circuit for turning off the bulb compares the output of the counter with a reference value.

7. An end-of-life LED light bulb as set forth in claim 5, wherein the reference value is randomly adjusted at production time.

8. An end-of-life LED light bulb as set forth in claim 6, wherein the reference value is randomly adjusted at production time.