关于带宽增益积,我的理解是放大器带宽和带宽增益的乘积是一个定值。按照我的理解,OPA657的带宽增益积是1600MHz,当增益G=10时,带宽应该为160MHz,可是Datasheet上说明的是275MHz,我该怎么理解?
谢谢大家!
其实这点在OPA657的datasheet Page 18中“频响控制”部分有详细的介绍,可以参考下,如有问题,可以继续讨论。
Ideally, dividing GBP by the noninverting signal gain (also called the noise gain, or NG) predicts the closed-loop bandwidth. In practice, this only holds true when the phase margin approaches 90°, as it does in high-gain configurations. At low gains (increased feedback factors), most high-speed amplifiers exhibit a more complex response with lower phase margin.