This disclosure provides a charging-steering amplifier circuit and the control method thereof. The charging-steering amplifier circuit includes a charging-steering differential amplifier and a sample and hold circuit. The charging-steering amplifier circuit operates in a reset phase or in an amplifying phase to amplify a differential input signal. The control method includes steps of: in the reset phase, obtaining a common mode voltage of the differential input signal according to the differential input signal; in the reset phase, providing the common mode voltage to one of the charging-steering differential amplifier and the sample and hold circuit; in the reset phase, sampling the differential input signal by the sample and hold circuit to generate a voltage signal; and in the amplifying phase, inputting the voltage signal to the charging-steering differential amplifier.

This disclosure provides a charging-steering amplifier circuit and the control method thereof. The charging-steering amplifier circuit includes a charging-steering differential amplifier and a sample and hold circuit. The charging-steering amplifier circuit operates in a reset phase or in an amplifying phase to amplify a differential input signal. The control method includes steps of: in the reset phase, obtaining a common mode voltage of the differential input signal according to the differential input signal; in the reset phase, providing the common mode voltage to one of the charging-steering differential amplifier and the sample and hold circuit; in the reset phase, sampling the differential input signal by the sample and hold circuit to generate a voltage signal; and in the amplifying phase, inputting the voltage signal to the charging-steering differential amplifier.

Telescopic amplifier circuits are disclosed. In an embodiment, a telescopic amplifier includes an input stage for receiving differential input signals, an output stage for outputting differential output signals at the drains of a first output transistor and a second output transistor, a tail current transistor coupled to sources of a first input transistor and a second input transistor, a common mode feedback circuit coupled to the differential output signals and outputting a common mode output signal, and a circuit element coupled between the common mode output signal and a gate of the tail current transistor. In an embodiment the circuit element is a resistor. In another embodiment the circuit element is a source follower transistor. In additional embodiments a phase margin of the common mode feedback open loop gain of the amplifier is determined by the value of the resistor. Additional embodiments are disclosed.

An operational amplifier circuit includes: a first differential amplifier section containing a P-type differential pair of P-type transistors; a second differential amplifier section containing an N-type differential pair of N-type transistors; an intermediate stage connected with outputs of the first and second differential amplifier sections and containing a first current mirror circuit of P-type transistors, and a second current mirror circuit of N-type transistors; and an output stage configured to amplify an output of the intermediate stage in power. The first differential amplifier section includes a first current source and a first capacitance between sources of the P-type transistors of the P-type differential pair and a positive side power supply voltage. The second differential amplifier section includes a second current source and a second capacitance between sources of the N-type transistors of the N-type differential pair and a negative side power supply voltage.

An amplifier includes a first stage amplifier circuit configured to receive an input voltage and a first multi-stage amplifier circuit and a second multi-stage amplifier circuit branching off from an output terminal of the first stage amplifier circuit and each including a second stage and a third stage. Each of the first multi-stage amplifier circuit and the second multi-stage amplifier circuit may be configured to sample a voltage corresponding to a first bias current corresponding to the second stage and a voltage corresponding to a second bias current corresponding to the third stage in a first phase, and bias the second stage with the voltage corresponding to the first bias current and bias the third stage with the voltage corresponding to the second bias current in a second phase.

Telescopic amplifier circuits are disclosed. In an embodiment, a telescopic amplifier includes an input stage for receiving differential input signals, an output stage for outputting differential output signals at the drains of a first output transistor and a second output transistor, a tail current transistor coupled to sources of a first input transistor and a second input transistor, a common mode feedback circuit coupled to the differential output signals and outputting a common mode output signal, and a circuit element coupled between the common mode output signal and a gate of the tail current transistor. In an embodiment the circuit element is a resistor. In another embodiment the circuit element is a source follower transistor. In additional embodiments a phase margin of the common mode feedback open loop gain of the amplifier is determined by the value of the resistor. Additional embodiments are disclosed.

Telescopic amplifier circuits are disclosed. In an embodiment, a telescopic amplifier includes an input stage for receiving differential input signals, an output stage for outputting differential output signals at the drains of a first output transistor and a second output transistor, a tail current transistor coupled to sources of a first input transistor and a second input transistor, a common mode feedback circuit coupled to the differential output signals and outputting a common mode output signal, and a circuit element coupled between the common mode output signal and a gate of the tail current transistor. In an embodiment the circuit element is a resistor. In another embodiment the circuit element is a source follower transistor. In additional embodiments a phase margin of the common mode feedback open loop gain of the amplifier is determined by the value of the resistor. Additional embodiments are disclosed.

An operational amplifier circuit includes: a first differential amplifier section containing a P-type differential pair of P-type transistors; a second differential amplifier section containing an N-type differential pair of N-type transistors; an intermediate stage connected with outputs of the first and second differential amplifier sections and containing a first current mirror circuit of P-type transistors, and a second current mirror circuit of N-type transistors; and an output stage configured to amplify an output of the intermediate stage in power. The first differential amplifier section includes a first current source and a first capacitance between sources of the P-type transistors of the P-type differential pair and a positive side power supply voltage. The second differential amplifier section includes a second current source and a second capacitance between sources of the N-type transistors of the N-type differential pair and a negative side power supply voltage.

A fully differential switched capacitor amplifier receives a differential analog signal from a differential input terminal, amplifies the differential analog signal, and outputs an amplified signal from a differential output terminal. The fully differential switched capacitor amplifier includes: a sampling capacitor that respectively samples the differential analog signal input from the differential input terminal; a differential input switch connected to a path for inputting the differential analog signal between the differential input terminal and the sampling capacitor; a fully differential amplifier that amplifies the differential analog signal input to the sampling capacitor; and a differential input resistor connected between the differential input switch and the sampling capacitor.