Patent ID: 7126623

Claim:
A serially connected LED lamps control device comprising: a plurality of shift registers, and an LED driver circuit, an internal latch signal is used to produce a circuit to reduce the quantity of connections and a plurality of circuits capable of delaying an output data for half cycle as to improve the stability of a system, wherein said LED driver circuit comprises a D-type latch being installed in front of said data output for an inverted clock synchronization and capable of delaying an outputted data for half cycle, and a clock loss detect circuit added to said control device, such that when said data is sent and the clock is stopped for a predetermined time, said circuit automatically generates a latch signal, and said latch signal is obtained by a latch signal selector and set to another D-type latch to latch the output data from said original S-R shift register as to generate an LED control signal and said LED driver circuit drives said LED lamps, thereby a connecting line is reduced; wherein said latch signal select circuit adds a circuit flexibility such that a system designer selectively adopts a desired internal and external latch signal as needed.