# US 2014/0152535 A1 · Led backlight driver circuit, lcd device and driving method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0152535 A1 - Document ID: US20140152535A1 - Status: Published application - Kind: A1 - Application number: 13/807,276 - Filed: 2012-12-07 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Assignees: Shenzhen China Star Optoelectronics Technology Co., Ltd. - Applicants: Shenzhen China Star Optoelectronics Technology co. Ltd - Inventors: Hua Zhang; Fei Li - Web page: https://patentgrep.com/patent/US20140152535A1 ## CPC - G09G 3/342: {using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines} - G09G 3/36: using liquid crystals - H05B 45/10: Controlling the intensity of the light - H05B 45/46: having LEDs disposed in parallel lines - G09G 2320/064: by time modulation of the brightness of the illumination source - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL ## Abstract A light emitting diode (LED) backlight driver circuit includes at least two lightbars which are independently driven, an output end of each lightbar is coupled with a constant current driver integrated circuit (IC), and a monitoring module controlling the constant current driver IC. The monitoring module outputs a phase delay time to drive each lightbar and a current duty of each lightbar to the constant current driver IC, and the constant current driver IC drives the lightbars one by one according to the corresponding current duty in accordance with the phase delay time in sequence. ## Claims ### Claim 1 A light emitting diode (LED) backlight driver circuit, comprising: at least two lightbars which are independently driven; and a monitoring module; wherein an output end of each of the lightbars is coupled with a constant current driver integrated circuit (IC), the monitoring module controls the constant current driver integrated circuit (IC) and outputs a phase delay time to drive each lightbar and a current duty of each lightbar to the constant current driver IC, and the constant current driver IC drives the lightbar one by one according to the corresponding current duty in accordance with the phase delay time in sequence. ### Claim 2 (depends on 1) The light emitting diode (LED) backlight driver circuit of claim 1, wherein the monitoring module obtains an enable signal (CS), a clock signal (SCK), and an output data signal (SDA) from a serial peripheral interface (SPI) of the LED backlight driver circuit, decodes and generates a current duty and the phase delay time for each of the LED lightbars, and directly sends the current duty and the phase delay time to the constant current driver IC. ### Claim 3 (depends on 1) The light emitting diode (LED) backlight driver circuit of claim 1, wherein the monitoring module outputs drive signals of all the lightbar in sequence to the constant current driver IC according to the phase delay time. ### Claim 4 (depends on 3) The light emitting diode (LED) backlight driver circuit of claim 3, wherein the constant current driver IC is configured with input pins corresponding to each of the lightbars, and the monitoring module inputs the drive signals of all the lightbar into the corresponding input pins. ### Claim 5 (depends on 3) The light emitting diode (LED) backlight driver circuit of claim 3, wherein the constant current driver IC is configured with only one input pin for each of the LED lightbars, the drive signals of all the lightbars are input to the input pin by the monitoring module, wherein the constant current driver IC comprises a switching module switching the drive signals of the input pin to the corresponding lightbars. ### Claim 6 (depends on 1) The light emitting diode (LED) backlight driver circuit of claim 1, wherein the monitoring module sends a phase delay time to drive two adjacent lightbars together with the current duty of all the lightbars to the constant current driver IC within one scanning period, wherein the one scanning period is a time to drive from a first lightbar to a last lightbar. ### Claim 7 (depends on 1) The light emitting diode (LED) backlight driver circuit of claim 1, wherein the monitoring module is a timing control module. ### Claim 8 A liquid crystal display (LCD) device, comprising: a light emitting diode (LED) backlight driver circuit, wherein the LED backlight driver circuit comprises at least two lightbars which are independently driven, an output end of each lightbar is coupled with a constant current driver integrated circuit (IC), and a monitoring module controlling the constant current driver IC; the monitoring module outputs a phase delay time to drive each lightbar and a current duty of each lightbar to the constant current driver IC, and the constant current driver IC drives the lightbar one by one according to the corresponding current duty in accordance with the phase delay time in sequence. ### Claim 9 (depends on 8) The liquid crystal display (LCD) device of claim 8, wherein the monitoring module obtains an enable signal (CS), a clock signal (SCK), and an output data signal (SDA) from a serial peripheral interface (SPI), decodes and generates the current duty and the phase delay time for each of the LED lightbars, and directly sends the current duty and the phase delay time to the constant current driver IC. ### Claim 10 (depends on 8) The liquid crystal display (LCD) device of claim 8, wherein the monitoring module outputs drive signals of all the lightbars in sequence to the constant current driver IC according to the phase delay time. ### Claim 11 (depends on 10) The liquid crystal display (LCD) device of claim 10, wherein the constant current driver integrated circuit (IC) is configured with input pins for each of the LED lightbars, and the monitoring module inputs the drive signals of all the lightbars into the corresponding input pins. ### Claim 12 (depends on 10) The liquid crystal display (LCD) device of claim 10, wherein the constant current driver integrated circuit (IC) is only configured with one input pin for each of the LED lightbars, the monitoring module inputs the drive signals of all the lightbars into the corresponding input pins, wherein the constant current driver IC comprises a switching module switching the drive signals of the input pin to the corresponding lightbars. ### Claim 13 (depends on 8) The liquid crystal display (LCD) device of claim 8, wherein the monitoring module sends a phase delay time to drive two adjacent lightbars together with the current duty of all the lightbars to the constant current driver integrated circuit (IC) within one scanning period; wherein the one scanning period is a time from driving a first lightbar to a last lightbar. ### Claim 14 (depends on 8) The liquid crystal display (LCD) device of claim 8, wherein the monitoring module is a timing control module. ### Claim 15 A light emitting diode (LED) backlight driving method, comprising: A. employing a monitoring module to generate a phase delay time between two lightbars and a current duty of each lightbar, and sending the phase delay time to drive each lightbar and the current duty of each lightbar to a constant current driver integrated circuit (IC); B. driving the lightbars one by one in accordance with the corresponding current duty in sequence according to the phase delay time by the constant current driver IC. ### Claim 16 (depends on 15) The light emitting diode (LED) backlight driving method of claim 15, wherein in the step A, the timing control circuit outputs drive signals of all the lightbars to the constant current driver IC in sequence according to the phase delay time. ### Claim 17 (depends on 16) The light emitting diode (LED) backlight driving method of claim 16, wherein the constant current driver IC is configured with input pins for each of the LED lightbars; in the step A, the monitoring module inputs the drive signals of all the lightbars into the corresponding input pins.