Regulated cascode circuits and cmos analog circuits include the same

Abstract

A regulated cascode circuit includes a first MOS transistor of a first conductive type, a second MOS transistor of the first conductive type, a third MOS transistor of a second conductive type, a first current source and a second current source. The first MOS transistor is coupled between an output node and a first node. The second MOS transistor having a gate terminal for receiving a bias voltage is coupled between the first node and a second power supply voltage. The third MOS transistor is coupled between the first power supply voltage and a gate terminal of the first MOS transistor. The first current source is coupled between the gate terminal of the first MOS transistor. The second current source is coupled between the first power supply voltage and the output node.

Description

field of invention [0001] The present invention relates to analogue circuits, and more particularly to regulated common-source-common-shelf amplifier circuits having stable operating characteristics at voltages below 1 volt, and CMOS analogue circuits comprising the same. Background technique [0002] Recently, as electronic devices are rapidly becoming lighter and thinner to satisfy mobility and portability in a mobile environment, there has been a trend of designing a system-on-chip SoC. [0003] Due to the demand for the ability to store a large amount of data and multi-functionality, the integration of semiconductor integrated circuits has become higher, and there is an increasing demand for low-power circuits to reduce battery power consumption. Consequently, most circuits are required to operate at less than 1 volt due to the ever-decreasing operating voltage. [0004] However, due to limitations in resolution and circuit structure, analog circuits require higher volt...

AI Technical Summary

Problems solved by technology

However, no such advances have been made in the search for ensuring large output impedance and large swing range

[0006] Increased leakage current across gate terminal and channel length variation by scaling down oxide thickness and channel length makes it difficult to achieve sufficient voltage gain

In addition, the low operating voltage makes it difficult to ensure the full output swing range of the cascode circuit

[0007] A regulated cascode amplifier circuit operating in the weak inversion region has been proposed to solve the above problems, but it has not been widely used due to problems related to unstable operation

Images