What does low power operational amplifier mean?

What does low power operational amplifier mean?

Definition of low-power operational amplifier
Since the biggest advantage of electronic circuit integration is that it can make complex circuits small and light, as the application range of portable instruments expands, operational amplifiers with low power supply voltage and low power consumption must be used. With the development of technology and the limited human resources, the energy-saving requirements for various application electrical appliances are getting higher and higher, which is the reason for the emergence of low-power operational amplifiers.

Selection of Integrated Operational Amplifiers
Integrated operational amplifiers are the most widely used devices in analog integrated circuits. In various systems composed of operational amplifiers, due to different application requirements, the performance requirements of operational amplifiers are also different.

In situations where there are no special requirements, try to use general-purpose integrated operational amplifiers, which can reduce costs and ensure supply. When multiple operational amplifiers are used in a system, try to use multi-op-amp integrated circuits, such as LM324, LF347, etc., which are integrated circuits that package four operational amplifiers together.

To evaluate the performance of an integrated operational amplifier, we should look at its comprehensive performance. The merit factor K is generally used to measure the quality of an integrated operational amplifier, which is defined as:

In the formula, SR is the conversion rate, the unit is V/ms, the larger the value, the better the AC characteristics of the op amp; Iib is the input bias current of the op amp, the unit is nA; VOS is the input offset voltage, the unit is mV. The smaller the Iib and VOS values ​​are, the better the DC characteristics of the op amp are. Therefore, for circuits that amplify AC signals such as audio and video, it is more appropriate to choose an op amp with a large SR (conversion rate); for circuits that process weak DC signals, it is more appropriate to choose an op amp with relatively high precision (i.e., the offset current, offset voltage and temperature drift are relatively small).

When selecting an integrated operational amplifier, in addition to the figure of merit, other factors should also be considered. For example, the nature of the signal source, whether it is a voltage source or a current source; the nature of the load, whether the output voltage and current of the integrated operational amplifier meet the requirements; environmental conditions, whether the integrated operational amplifier's allowable operating range, operating voltage range, power consumption and volume meet the requirements.

Characteristics of low-power operational amplifiers:
The characteristics of low-power operational amplifiers are that the power supply current can be properly adjusted by connecting a resistor or a constant current source outside the IC, and various parameters can be obtained at the same time. It can operate in the range of positive or negative 3 to positive or negative 18V and can also be used as a functional operational amplifier.

The application of low-power operational amplifiers
is suitable for use in equipment powered by dry batteries. It can be used in operational amplifiers that are powered by low power supply voltage and have low power consumption.