Abstract: Embodiments of the present invention disclose operational amplifiers which demonstrate good settling behavior with minimum over-shoot or ringing for improving settling behavior. The amplifiers include one or more amplification stages connected to form a symmetric structure. The amplification stage includes a boosting amplifier, a MOS transistor and a compensation capacitor. The MOS transistor can be an NMOS transistor and a PMOS transistor. Using this scheme pole-zero doublets are rearranged in a manner to improve the transient settling response.

Abstract: A continuous time common mode feedback module is capable of operating in a wide range of input voltages. The common mode feedback module includes a common mode detector and an amplifier for computing and amplifying the difference of a reference voltage and a common mode voltage of a first input signal and a second input signal. The common-mode feedback module includes a common mode resolver and a control voltage generating module coupled to each other to provide a common mode feedback voltage. The common mode feedback module provides a good linearity and a wide bandwidth, without compensation requirements. The common mode feedback module also provides small process corner dependence of bias current and a common mode offset.

Abstract: Embodiments of the present invention provide a low voltage continuous time common mode feedback (CMFB) module, for low voltage operational amplifiers, providing good linearity, wide bandwidth and low systematic offset. The common mode feedback module includes a controlling module and an initializing module. The controlling module and the initializing module are parallel common mode feedback loops. The controlling module is a main CMFB loop and the initializing module is an auxiliary CMFB loop and both the loops work simultaneously. The controlling module and the initializing module receive a first differential input voltage and a second differential input voltage supplied by differential outputs of a main differential amplifier. Both the CMFB loops are low gain amplifiers in order to provide operation as linear as possible over the entire differential output operating range of the main differential amplifier.