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In general, a single supply opamp operates by supplying VCC (VDD) to the 0V (ground) reference, while a dual supply opamp is used by supplying a positive voltage to VCC as a reference (ground) and negative voltage to VEE. If the input voltage does not exceed the common mode input voltage range either type can be used. Select a single or dual supply type from the dynamic input/output voltage ranges.
When reverse voltage is supplied to the supply and ground pins, current flows through the electrostatic protection diodes between the VCC (VDD) and VEE (VSS) pins, which can lead to current degradation and, ultimately, destruction.
The output and current consumption of unused circuits can be stabilized by short-circuiting the output and inverting input pin (voltage follower), and connecting the non-inverting input pin to a voltage within the common mode input voltage range. In the case of a ground sense type opamp the input can be pulled down to VEE.
When the input terminals are shorted the output is amplified by the input offset voltage multiplied by the open loop gain and the maximum output voltage is High or Low, but if the shorted input is floating the output will become unstable. Therefore, it is recommended that a fixed voltage within the common mode input voltage range be supplied.
The recommendation is to set the inputs to within the common mode input voltage range in a voltage follower configuration, but even if all of the I/O are open there should be no problems such as malfunction or destruction when using these products.
PSRR is the ratio of the change in input offset voltage with respect to the change in power supply voltage. The standard used in the datasheet is DC Variation. PSRR=20log(Power Supply Variation)/(Input Offset Voltage Variation)[dB]. Generally, PSRR is frequency dependent, and decreases as the frequency increases.
The main factor is the relative error in pairing of differential input stage transistors. The variations generally follow a normal distribution. Please refer to the technical materials for more information.Related Link:Technical Document
The maximum input offset voltage is expressed as an absolute value. For example, for products with a maximum value of 5mV, the input offset voltage is spread across the range from -5mV to +5mV.