Inverter controller

• US 6,856,519 B2
• Filed: 05/06/2002
• Issued: 02/15/2005
• Est. Priority Date: 05/06/2002
• Status: Expired due to Fees

• Current Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Original Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Inventors: Lin, Yung-Lin, Liu, Da
• Primary Examiner(s): HAN, YOUNGHUIE JESSICA
• Application Number:
  US10/139,619
• Publication Number:
  US 20030206426A1
• Time in Patent Office: 1,016 Days
• Field of Search: 345/204, 345/205, 345/208, 345/210, 345/211, 345/212, 315/306, 315/307, 363/25, 363/16, 363/17, 363/132, 713/1, 323/905
• US Class Current: 363/16
• CPC Class Codes: H02M 7/53806 in a push-pull configuration of the parallel type
• CPC Class Codes: H05B 41/2824 using control circuits for the switching element H05B41/2822 takes precedence
• CPC Class Codes: H05B 41/3927 by pulse width modulation H05B41/3922 takes precedence
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
• CPC Class Codes: Y10S 323/905 Lamp dimmer structure

Abstract

An integrated circuit inverter controller that includes at least one input pin that is configured to receive two or more input signals. The input pin may be multiplexed so that the appropriate input signal is directed to appropriate circuitry within the controller to support two or more functions of the controller. Alternatively, the input signals may be present in differing time periods so that a single pin can support two or more functions. Multifunctional or multitasked pins reduce the overall pin count of the inverter controller.

Claims

1. A system, comprising:

one or more cold cathode fluorescent lamps;

an inverter circuit generating an AC signal to power said one or more lamps; and

an inverter controller adapted to generate a plurality of signals to drive said inverter circuit, said controller comprising at least one input pin configured to receive at least two independent input signals, each said input signal supporting an associated function of said controller during operation of said controller.

2. The system as claimed in claim 1, wherein said inverter circuit is selected from a push-pull, half bridge and full-bridge inverter topologies for converting a DC signal to said AC signal.

3. The system as claimed in claim 1, wherein said inverter circuit comprises a plurality of power switches for converting a DC signal to said AC signal.

4. The system as claimed in claim 1, wherein said inverter circuit comprises a step-up transformer receiving said AC signal and generating a stepped-up AC signal.

5. The system as claimed in claim 1, wherein said input pin configured to operate with a first signal representing a dim voltage, said first signal having a first voltage range;

and a second signal representing a voltage feedback signal indicative of voltage supplied to said CCFL, said second signal having a second voltage range.

6. The system as claimed in claim 1, further comprising a multiplexer circuit to direct one of said input signals to a first circuit to support a first said function of said controller, and to direct another of said input signals to a second circuit to support a second said function of said controller.

7. The system as claimed in claim 1, wherein one of said input signals is present in a first time period and another of said input signals is present in a second time period.