Actual op amp parameters

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1. Input offset voltage (VIO): Input offset voltage, referred to as VIO, is defined as the compensation voltage between the two input terminals required to make the output of the operational amplifier 0V (or close to 0V). The VIO of an ideal operational amplifier is 0V, generally in the millivolt level. The smaller this parameter is, the better. It reflects the symmetry of the circuit in the manufacture of the operational amplifier. 2. Input bias current (IIB): Bias current is the average value of the base DC current of the input transistor of the first stage amplifier. The smaller this parameter is, the better. 3. Input offset current (IIO): Input offset current (input offset current) is the absolute value of the difference between the input bias currents of the two input terminals. The smaller the value, the better. 4. Differential input resistance (RIN): Input resistance (input resistance) is the differential input resistance between the two input terminals. The larger the value, the better. 5. Differential voltage gain (AVD): Also known as differential voltage gain, it refers to the ratio of the change in output voltage to the change in input voltage, that is, the voltage amplification factor. The AV of an ideal amplifier is infinite, and the actual op amp is generally greater than 80dB. 6. Common-mode voltage gain (AVC): The ratio of the change in output voltage to the change in input voltage when the differential voltage is input to the two input terminals. 7. Maximum output voltage (VOM): For an actual operational amplifier, if the amplitude becomes larger, the output signal approaches the positive and negative power supply voltages and enters a saturated state, resulting in distortion. The maximum voltage before distortion occurs is called the maximum output voltage. 8. Common-mode input voltage range (VICM): This indicates the range of common-mode voltage that can be applied between the two input terminals of the operational amplifier and the ground. 9. Common-mode rejection ratio (KCMR): The ratio of the differential-mode voltage gain AVD to the common-mode voltage gain AVC is called the common-mode rejection ratio. It can be expressed as KCMR = 20lg (AVD / AVC) dB. The larger this value is, the better, but it will decrease as the frequency of the signal increases, and is generally greater than 80dB. 10. Power supply voltage rejection ratio (KSVR): The rate of change of the offset voltage of the operational amplifier with the power supply is called the power supply voltage rejection ratio. That is, the degree to which the output signal is affected by the power supply voltage. If the offset voltage changes by △VS when the power supply changes by △VIo, then KSVR is defined as: KSVR=20lg（△VS/△VIo）dB. The larger this value is, the better. When it is smaller, power supply noise appears in the output. 11. Current consumption (ICC): This is the current flowing through the power supply terminal of the operational amplifier, which varies with the difference between the external circuit and the power supply voltage. The smaller the current consumption is, the better. When it is larger, the amplifier heats up and causes the output DC drift to increase. 12. Conversion rate (SR): If the input signal changes quickly, the output cannot keep up with the speed of the input change. SR is a parameter that represents this tracking performance. The larger the value, the better, but the other performance of the operational amplifier with a high value is poor. 13. Gain bandwidth product (GB): A parameter that represents the voltage gain-frequency characteristics, with the unit of MHZ. (Unit gain bandwidth). 11. Current consumption (ICC): This is the current flowing through the power supply terminal of the operational amplifier, which varies with the external circuit and the power supply voltage. The smaller the current consumption, the better. When the current consumption is larger, the amplifier heats up and causes the output DC drift to increase. 12. Conversion rate (SR): If the input signal changes quickly, the output cannot keep up with the input change speed. SR is a parameter that represents this tracking performance. The larger the value, the better, but the operational amplifier with a high value has poor other performance. 13. Gain bandwidth product (GB): A parameter that represents the voltage gain-frequency characteristics, with the unit of MHZ. (Unit gain bandwidth).