← 返回 JSSC 论文列表JSSC 2008第10期RF & Wireless0.18μm
Chopper Stabilization of Analog Multipliers Variable Gain Amplifiers and Mixers
采用斩波稳定技术实现模拟乘法器的超低偏移设计
1.5μV残余偏移(同类最佳)
斩波稳定模拟乘法器偏移消除可变增益放大器直接下变频混频器
▸创新点1:采用正交扩频码的双级斩波技术,通过两级调制和正交编码有效分离信号与偏移,将残余偏移降低至微伏级(1.5μV),相比传统方法提升两个数量级。
▸创新点2:实现微伏级偏移消除能力,通过连续斩波调制和滤波技术,克服了传统方法对漂移敏感的缺陷,在DC乘法器中达到文献报道的最低偏移水平。
▸创新点3:系统级创新在于同时抑制1/f噪声和谐波失真,通过斩波技术不仅消除直流偏移,还显著改善AC乘法模式下的信噪比(实测49dB噪声抑制)和线性度。
▸创新点4:提出电荷注入尖峰残余偏移的详细分析模型,量化了斩波频率与偏移的关系,为高频应用中的精度极限提供设计指导(支持0.18μm工艺验证)。
Abstract
We describe a general offset-canceling architecture
for analog multiplication using chopper stabilization. Chopping
is used to modulate the offset away from the output signal where
it can be easily filtered out, providing continuous offset reduction
which is insensitive to drift. Both square wave chopping and
chopping with orthogonal spreading codes are tested and shown
to reduce the offset down to the microvolt level. In addition, we
apply the nested chopping technique to an analog multiplier wh