End-of-life bulb circuitry

• US 9,107,273 B2
• Filed: 09/08/2009
• Issued: 08/11/2015
• Est. Priority Date: 09/11/2008
• Status: Expired due to Fees

• Current Assignee: Switch Bulb Company, Inc.
• Original Assignee: Switch Bulb Company, Inc.
• Inventors: Lenk, Ronald J., Lenk, Carol, Thorman, Ethan
• Primary Examiner(s): Owens, Douglas W
• Assistant Examiner(s): CHO, JAMES HYONCHOL
• Application Number:
  US13/062,195
• Publication Number:
  US 20110210669A1
• Time in Patent Office: 2,163 Days
• Field of Search: 315/360, 315/361, 315/291, 315293-295, 315/312, 315/307, 315/308
• US Class Current: 1/1
• 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 LED light bulb comprising:

an LED light bulb;

a microcontroller having a circuit configured to detect operational time of the bulb;

wherein the microcontroller is configured to disable the bulb upon reaching a preset amount of operational time and wherein the circuit is configured to compare an output of the circuit with a reference value; and

wherein the reference value is randomly adjusted at production time.

2. An end-of-life LED light bulb comprising:

an LED light bulb;

a microcontroller having a circuit configured to detect operational time of the bulb;

wherein the microcontroller is configured to disable the bulb upon reaching a preset amount of operational time and wherein the microcontroller includes a non-volatile memory;

wherein the circuit is configured to compare an output of a counter with a reference value; and

wherein the reference value is randomly adjusted at production time.

3. An end-of-life detecting light emitting diode (LED) light bulb comprising:

a shell;

a base connected to the shell, the base configured to receive an alternating current (AC);

an LED within the shell;

a microcontroller having a circuit, the circuit configured to detect operational time of the bulb, wherein the microcontroller is connected to the LED and wherein the microcontroller is configured to receive a rectified AC input based on the AC;

wherein the microcontroller disables the bulb based on reaching a preset amount of operational time; and

wherein the microcontroller is configured to compare a counter value with a reference value, the reference value is randomly adjusted at production time.

4. The end-of-life LED light bulb of claim 3, wherein:

the microcontroller is configured to detect AC line cycles of the rectified AC input; and

the operational time of the bulb is based on the detected AC line cycles.

5. The end-of-life LED light bulb of claim 4, the circuit further comprising:

a counter circuit, the counter circuit configured to count based on the detected AC line cycles wherein the counter value based on the detected AC line cycles.

6. The end-of-life LED light bulb of claim 3, wherein the microcontroller includes a non-volatile memory.

7. The end-of-life LED light bulb of claim 6, wherein the microcontroller is configured to read from the non-volatile memory at bulb power-up and the microcontroller is configured to write to the non-volatile memory at bulb power-down.