Research And Design On The Key Modules Of High-Resolution Pipelined ADC

ADC, as an indispensible part of data converter, is developing rapidly along with microelectronics technology, with a growing demand for speed and precision from market. Due to its optimum balance of speed, precision and power consumption, pipelined ADC is widely used.Sample and Hold (S/H) and bandgap reference, as two key modules of pipelined ADC, exert direct influence on the overall performance. Moreover, linear and nonlinear properties of sampling switch, a basic component of S/H, have a critical impact on the speed and precision of S/H. This thesis mainly seeks to design a market-oriented sampling switch and reference of S/H in pipelined ADC.Based on detailed analyses of the structure and operation principles of high precision pipelined ADC, performance requirements for sampling and reference in S/H are presented. Then this thesis designed the bootstrapped switch and the reference by the requirements respectively, which substantially enhanced the overall performance of S/H and optimized the temperature coefficient and power supply rejection ratio of the reference.Finally, this thesis accomplished the layout and post-simulation of the bootstrapped switch and the reference under0.35um CMOS process. And the test results of tape-out indicated that the designs met the project requirement.The key technique issues solved in this thesis are as follow:(1)It simplifies the structure and reduces the layout area requirements of bootstrapped switch, without any increase of the clock signal. The linearity of the sampling switch is improved and the complexity of the circuit is reduced, which significantly improves the performance of S/H.(2) Without any increase of the complexity of reference circuit, An innovative bandgap reference (BGR) using negative feedback achieve non-linear compensate is designed. The circuit uses a negative feedback bandgap core to optimize the temperature coefficient, power supply rejection and line regulation.