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With the advancement of technology and electronic technology continues to evolve , the requirements for large screen display , the ordinary universal power driver chip has been far from satisfying the requirements . LED display gradually attracted attention as a high-tech electronic products , it has been widely used in telecommunications, postal services , financial services, transportation , stadiums and outdoor advertising industries and government departments . At the same time, the requirements of the people on the LED display development to large-screen , high uniformity , high picture quality , long-life direction , Therefore , a multi- channel , highly accurate output current dedicated LED driver chips become the focus . This paper introduces in detail with a protective function 16 channel dedicated LED constant current drive control chip design , as well as the simulation of several functional modules and performance indicators . The chip design requirements operating voltage range of 3.3V-5V, 3mA- 60mA output current range of each channel , and precisely adjustable output current size , clock frequency up to 25MHz, to meet the requirements of the transmission of large amounts of data . The circuit design including SDI input port module , module the SDO output port module , voltage reference module , the current regulation , overtemperature protection module , output stage module module circuit . This article is based on a 0.35um mixed signal CMOS process , using Cadence working platform , each module circuit simulation , and on this basis the overall circuit the joint functional simulation and test analysis . Chip output current of the internal error of less than 3% of the output current between the chip error is less than 6% , compared to the previous commonly used 16-channel LED constant current drive , better output current regulation accuracy and higher current matching accuracy, and also has a smaller chip area , industrial production can greatly improve chip yield and significantly reduce the cost of production per unit of chip .
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