摘要
基于传统的多级运放结构设计了一款低失调,高速高精度的运算放大器。在传统运算放大器的基础上引入Ping-Pong自调零技术结合多级密勒补偿技术,实现了低失调,低噪声以及高精度。采用SMIC 0.18μm CMOS工艺,5 V电压下进行仿真验证。通过Spectre仿真,电路单位增益带宽为9MHz,输出精度达到0.5%。
Based on the traditional multistage amplifier structure, a large bandwidth, high precision amplifier circuit is designed. On the basis of traditional amplifier, the ping-pong auto-zeroing and multistage miller compensation technology are introduced to achieve low offset, low noise and high precision. At the power supply voltage of 5 V, the SMIC 0.18μm CMOS process was used to verify the designed circuit. Through Cadence simulation, the circuit has a unity-gain bandwidth of 9 MHz, the output accuracy reaches one in a thousand, batter than the traditional amplifier.
引文
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