分贝数(dB)本来是表示功率之比的,后来又用来表示电压之比,尤其是在集成运算放大器中,往往都以分贝数来表示开环增益;但是必须注意,两者的数量比与分贝数的换算关系是不同的:对于电压之比分贝数=20log(Vout/Vin)对于功率之比分贝数=10log(Pout/Pin)本文所指的分贝数,仅表示电压增益, The decibels (dB) were originally used to represent the ratio of power and later used to indicate the voltage ratio, especially in integrated op amps, where the open-loop gain was often expressed in decibels; however, it must be noted that the ratio between the two The ratio of decibels to decibels is different: the ratio of the voltage to the number of decibels = 20log (Vout / Vin) The decibel ratio for the power ratio = 10log (Pout / Pin) Decibels referred to herein represent only the voltage gain,