一种高精度片内电阻校准电路设计

Design of a High-Precision Calibration Circuit for On-chip Resistances

设计了一种适用于40Ω~100Ω内调节的高精度片内电阻校准电路,该电路可精确调整因工艺波动产生变化的片内电阻阻值。片内电阻校准电路采用模数混合控制方法,即以片外电阻为基准,采用高精度回滞比较器比较片内和片外电阻转换的电压值,采用自适应控制电路精确调整电阻阵列开关,使得片内电阻的阻值与片外基准电阻的阻值相等。电路基于40nm CMOS工艺进行设计,仿真结果表明,比较器的电压比较阈值最小为2mV,电路实现40Ω~100Ω内电阻阻值可调节,校准误差小于2%。

A high precision on-chip resistance calibration circuit with the adjustment range of 40Ωto 100Ωwas designed,which could accurately calibrate the on-chip resistance value caused by process fluctuation.The analogdigital mixing method was used.Combined with adaptive control circuits and high precision hysteresis comparators,the voltage values converted by the on-chip resistance and the referenced off-chip resistance were compared.The circuit was designed to make the on-chip resistance value equal to that of the referenced off-chip.The calibration circuit was designed in a 40nm CMOS process.The simulation results showed that the minimum voltage comparison threshold of comparator was 2mV.The circuit could achieve adjustable resistance values in the range of 40Ωto 100Ω,and the calibration error was less than 2%.