Invention Grant
- Patent Title: LED drive circuit
- Patent Title (中): LED驱动电路
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Application No.: US12323149Application Date: 2008-11-25
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Publication No.: US08110997B2Publication Date: 2012-02-07
- Inventor: Yasunori Muramatsu
- Applicant: Yasunori Muramatsu
- Applicant Address: US TX Dallas
- Assignee: Texas Instruments Incorporated
- Current Assignee: Texas Instruments Incorporated
- Current Assignee Address: US TX Dallas
- Agent John J. Patti; Wade J. Brady, III; Frederick J. Telecky, Jr
- Priority: JP2007-307719 20071128
- Main IPC: H05B37/00
- IPC: H05B37/00 ; H05B39/00 ; H05B41/00 ; H05B37/02

Abstract:
A LED drive circuit equipped with oscillator 18, up/down counter 20, and DAC 22 in order to drive multiple LEDs 10(1)-10(m) in a block. Up/down counter 20 carries out count-up/down operations in sync with clock CLK sent from oscillator 18 during the ramping up/down of pulse-lighting of the LEDs. DAC 22 converts counter count value DN into analog voltage signal VDAC and supplies it to the gate terminal of NMOS transistor 14 via low-pass filter 28 and buffer amplifier 24.
Public/Granted literature
- US20090174338A1 LED DRIVE CIRCUIT Public/Granted day:2009-07-09
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