Electric lamp and discharge devices: systems – Plural load device systems
Reexamination Certificate
2011-08-02
2011-08-02
Chang, Daniel D (Department: 2819)
Electric lamp and discharge devices: systems
Plural load device systems
C340S815450, C345S046000
Reexamination Certificate
active
07990081
ABSTRACT:
Methods and apparatus for implementing and operating pulse width modulation based LED dimmer controllers are described. A synchronization protocol is used to allow control information for the dimmer operations to be transferred to the PWM dimmer control clock domain from an external clock domain, such that visual artifacts are prevented when the control information is updated. Control information may be transferred to the LED dimmer controller via an I2C serial bus, and the synchronization protocol waits for an I2C STOP condition before updating control information across clock domain boundaries. The leading and trailing edges of an asserted group dimmer control signal are generated such that the active portion of the group dimmer control signal overlaps the active portion of individual LED pulse width modulated control signals. In this way, the pulse width modulation of the individual LED control signals is not cut off, or reduced in width by the group dimmer signal.
REFERENCES:
patent: 6449289 (2002-09-01), Quicksall
patent: 7317403 (2008-01-01), Grootes et al.
patent: 2004/0155608 (2004-08-01), Trinschek et al.
patent: 2005/0243022 (2005-11-01), Negru
patent: 2006/0244396 (2006-11-01), Bucur
patent: 2007/0046485 (2007-03-01), Grootes et al.
patent: 101253813 (2008-08-01), None
patent: 1589519 (2005-10-01), None
patent: 1748411 (2007-01-01), None
patent: 2007/023454 (2007-03-01), None
Philips Semiconductors: “HEF4094B MSI Data Sheet”, HEF4094B, Jan. 1995.
Texas Instrument: “CD74HC4094 Data Sheet-”. CD74HC4094, Nov. 1997.
Yamaguchi, Hiroshi, et al. “Dimming Apparatus for Game Machine” Patent Abstracts of Japan, Publication No. 20030126371, Date of Publication: Jul. 5, 2003 (Computer Translation).
Anderson Alma
Chandran Manoj
Chang Daniel D
NXP B.V.
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