一种增益提升和摆率增强的运算跨导放大器

An operational transconductance amplifier with gain boostingand slew rate enhancement

为了解决传统电流镜运算跨导放大器(OTA)在低压、低功耗条件下增益和摆率严重受限的问题,提出了一种基于互补翻转电压跟随器(FVF)的运算跨导放大器,有效提升跨导和最大输出电流,从而达到增益提升和摆率增强的目的。采用SMIC 0.18μm CMOS工艺进行设计和验证。仿真结果表明,在1.8 V电源电压下,与同等静态功耗的传统电流镜OTA相比,提出的互补FVF型OTA增益提高了11 dB,单位增益带宽提升了2倍,正、负摆率分别提升了6.7倍和6.1倍,比单FVF型OTA有更好的性能提升效果。

The gain and the slew rate of conventional current-mirror operational transconductance amplifiers(OTAs)are seriously limited under low voltage and low power consumption conditions.To solve the problem,an OTA based on complementary flipped voltage follower(FVF)is proposed.By effectively increasing the transconductance and the output current,the proposed OTA improves the gain and the slew rate.The design and verification is performed under SMIC 0.18μm CMOS process.The simulation results show that,at 1.8 V supply voltage,compared with the conventional current-mirror OTA which has the same static power consumption,the proposed OTA with complementary FVF improves the gain by 11 dB,enhances the unit gain bandwidth by 2 times,boosts the positive and negative slew rates by 6.7 and 6.1 times,respectively.The proposed OTA achieves a better performance than the OTA with single FVF.