Operational amplifier

Abstract

The embodiment of the invention discloses an operational amplifier. The operational amplifier comprises a rail-to-rail input stage circuit, a transient enhancement circuit and a class AB output stagecircuit, the transient enhancement circuit comprises a first comparator and a second comparator, wherein the first input end and the second input end of the first comparator are electrically connectedwith the first input end and the second input end of the rail-to-rail input stage circuit respectively; the grid electrode of the first transistor is electrically connected with the output end of thefirst comparator, and the drain electrode of the first transistor is electrically connected with the first input end of the class AB output stage circuit; the first input end and the second input endof the second comparator are electrically connected with the first input end and the second input end of the first comparator respectively; and the grid electrode of the second transistor is electrically connected with the output end of the second comparator, and the drain electrode of the second transistor is electrically connected with the second input end of the class AB output stage circuit.According to the operational amplifier provided by the embodiment of the invention, the slew rate of the output end of the operational amplifier is improved through the transient enhancement circuit.

Description

technical field [0001] Embodiments of the present invention relate to an operational amplifier control technology, in particular to an operational amplifier. Background technique [0002] With the development of electronic devices and semiconductor technology, operational amplifiers are used more and more widely. There are many types of operational amplifiers and are widely used in the electronics industry. When operational amplifiers have requirements for speed, the output terminal voltage needs to be established within a certain period of time. To the target value, that is, the slew rate at the output of the operational amplifier is required to be relatively large. [0003] At present, existing operational amplifier circuits such as rail-to-rail input class AB output op amps, if there is a requirement for the slew rate, the usual practice is to increase the slew rate by increasing the current in the tail current source of the input stage of the op amp However, this requir...

AI Technical Summary

Problems solved by technology

[0003] At present, existing operational amplifier circuits such as rail-to-rail input class AB output op amps, if there is a requirement for the slew rate, the usual practice is to increase the slew rate by increasing the current in the tail current source of the input stage of the op amp However, this requires increasing the output stage current of the op amp to ensure system stability. An increase in the output stage current of the op amp will increase the size of the output tube, resulting in a larger parasitic capacitance, resulting in a poorer effect of increasing the slew rate.

Images