论文部分内容阅读
为了降低高精度电流舵型数模转换器(DAC)中由于工艺电学梯度等原因导致的电流源失配,提出了一种基于阶梯状布局的电流源梯度误差补偿方法.该方法采用阶梯状电流源布局,以消除电流源的线性梯度误差,在此基础上设计了一种优化的电流源开关序列,用于补偿电流源的二次误差;同时将H型和树状结构应用在电流源阵列的电源布线中,消除电压梯度引入的失配误差.通过Matlab仿真对比证明该方法可有效提高DAC线性度.将此机制应用在一款12bit电流舵型DAC芯片中,其电流源阵列版图具有规整性和紧凑性的特点,芯片测试表明:此DAC的积分非线性误差小于最低有效位的9/10,微分非线性误差小于最低有效位的1/5.
In order to reduce the current source mismatch caused by process electrical gradients in high-precision current-steering DACs, a current-source gradient error compensation method based on stair-like layout is proposed, which uses step-like current Source layout to eliminate the linear gradient error of the current source. Based on this, an optimized current source switch sequence is designed to compensate for the quadratic error of the current source. At the same time, H-type and tree structures are applied to the current source array Of the power wiring to eliminate the mismatch error introduced by the voltage gradient.Compared with Matlab simulation shows that the method can effectively improve the DAC linearity.This mechanism is applied to a 12bit current steering DAC chip, the current source array layout has a regular The chip test shows that the integrated nonlinear error of the DAC is less than 9/10 of the least significant bit and the differential nonlinearity error is less than 1/5 of the least significant bit.