一种基于斩波调制的低压高精度CMOS带隙基准源

实现了一种适用于SOC的低压高精度带隙基准电压源设计。利用斩波调制技术有效地减小了带隙基准源中运放的失调电压所引起的误差,从而提高了基准源的精度。考虑负载电流镜和差分输入对各2%的失配时,该基准源的输出电压波动峰峰值为0.31 mV。与传统带隙基准源相比,相对精度提高了86倍。在室温下,斩波频率为100 kH z时,基准源提供0.768 V的输出电压。当电源电压在0.8 V到1.6 V变化时,该基准源输出电压波动小于0.05 mV;当温度在0°C到80°C变化时,其温度系数小于12 ppm/°C。该基准源的最大功耗小于7.2μW,采用0.25μm 2P 5M CM O S工艺实现的版图面积为0.3 mm×0.4 mm。

A Low Voltage and High Accuracy Bandgap Reference with Chopped Modulator

A design of a low voltage bandgap reference(BGR),for SOC application with high accuracy is described.To compensate the error caused by the offset of the opamp,the chopper modulator is used in the BGR circuit.Considering 2% mismatch of current-mirror and input pairs respectively,the peak-to-peak value of the output ripple is 0.31 mV.The relative accuracy is increased by 86 times compared with the BGR without chopped modulator.The design features a reference voltage of 0.768 V at 27(°C) and chopped frequency 100 kHz.With supply voltage range from 0.9 V to 1.6 V,the variation of the output is approximately 0.05 mV,and the temperature coefficient is less than 12 ppm/(°C) at temperature range from 0(°C) to 80(°C).The maximum power dissipation is less than 7.2 μW and the area of layout is about 0.3 mm×0.4 mm with a standard 0.25 μm 2P5M CMOS process.