The Design Of A Voltage Scaling 8-Bit DAC

The DAC is often used as input/output circuit of digital electronic system and analog electronic system. In the front and the end of the advanced electronics system, digital to analog converters (D/A converters) are applies to improve the performance of the digital processing technique.The D/A converter is a Low-Power, 8-Bit Quad DAC with Rail-to-Rail Output Buffers and relevant bandgap reference circuit which can drive the load. It is voltage scaling DAC. It operates from a single 4.5V-5.5V power supply.The simulation results obtained show that the functions and performances of this DAC chip meet the spec well. The simulation shows that the 8-bit D/A converter meet the requirements. The D/A converter can work well, the INL is not more than 0.5LSB, and the DNL is not more than 1LSB. The D/A converter's working current are no more than 600uA while driving 10K?. The working current is no more than 10uA in lower power mode.The design was based on the XFAB 0.6μm-BiCMOS process. It has been tapped out.In the thesis, I bring forward a new framework of DAC. It has two step framework of the resistance part. The number of resistance is reduced from 256 to 32. It retrenches the area of layout observably.During the design, we followed full-custom design methodology: confirm the spec-circuit design-simulation-layout design- tap out. The EDA tools used in the design includes the Virtuoso custom design platform, the simulation tool-Spectre and the verification tool-DIVA.