Differential amplifier, digital-to-analog converter, and display device

Abstract

Disclosed is a differential amplifier of a multi-level output type comprising a load circuit including a diode-connected first transistor with a source thereof connected to a power supply and a second transistor with a source thereof connected to the power supply and connected to a gate of the first transistor through a capacitor, a differential pair including a third transistor and a fourth transistor with sources thereof connected in common and drains thereof connected to drains of the first and second transistors, respectively, a current source for supplying a current to the differential pair, a first switch connected between a gate of the second transistor and a drain of the fourth transistor, an amplifier with an input thereof connected to a drain of the second transistor and an output thereof connected to an output terminal, a second switch connected between a gate of the fourth transistor and a first input terminal, a third switch connected between the gate of the fourth transistor and a third input terminal, a fourth switch connected between a gate of the third transistor and a second input terminal, and a fifth switch connected between the gate of the third transistor and the output terminal. Switching control between a first state where the first, second and fourth switches are turned on and the third and fifth switches are turned off and a second state where the first and second fourth switches are turned off and the third and fifth switches are turned on is performed.