Multiplying digital-to-analog converter (MDACs) are implemented in pipelined ADCs to generate an analog output being fed to a subsequent stage. A switched capacitor MDAC can be implemented by integrating a capacitor digital-to-analog converter (DAC) with charge pump gain circuitry. The capacitor DAC can implement the DAC functionality while the charge pump gain circuitry can implement subtraction and amplification. The resulting switched capacitor MDAC can leverage strengths of nanometer process technologies, i.e., very good switches and highly linear capacitors, to achieve practical pipelined ADCs. Moreover, the switched capacitor MDAC has many benefits over other approaches for implementing the MDAC.

A pipeline ADC architecture with suitable feedback can implement noise shaping. By feeding back the residue generated by the last residue generating stage to selected locations in the pipeline ADC, the delays in a pipeline ADC can create a finite impulse response (FIR) filtered version of the quantization error. The FIR filtered quantization error is added to the signal and evaluated by the pipeline ADC, which results in spectral shaping of the quantization noise. Unlike a conventional pipeline ADC, the output of the backend stage is scaled and filtered by a noise transfer function (NTF) of the residue generating stages prior to combining the output with other outputs of the pipeline ADC. The processing of the shaped quantization noise by the backend stage results in further noise suppression.

A method of incorporating Programmable Gain Amplifier (PGA) function into pipelined ADC for wide input range. The power consumption is saved without adding extra stage to reduce input range. The ADC input range can be adjusted on the fly using resistor bank and capacitor bank to achieve optimal system performance.

A pipelined analog-to-digital converter (ADC) circuit includes a first ADC stage and a residue stage coupled to the first ADC stage. The residue stage includes a dynamic integrator configured to provide transconductance, wherein the dynamic integrator includes a boost circuit configured to boost an output impedance of the transconductance.

In accordance with an embodiment, a method for monitoring a data converter configured to convert data using a calibration determined by a calibration data record includes calibrating the data converter in order to determine a corresponding multiplicity of time associated calibration data records at a multiplicity of different times; and determining a state of the data converter based on comparing at least one of the multiplicity of time associated calibration data records with a comparison data record.

A switched-capacitor gain stage circuit and method include an amplifier connected to an input sampling circuit with sampling switched capacitors for coupling an input voltage and a first or second reference voltage to one or more central nodes during a sampling phase and for coupling the one or more central nodes to an amplifier input during a gain phase, wherein a reference loading circuit uses a plurality of sampling switched capacitors connected in a switching configuration to selectively couple a first reference voltage and/or a second reference voltage to the central node by pre-charging the plurality of sampling switched capacitors with the first and second reference voltages during the sampling phase, and by coupling each of the first and second reference voltages to at least one of the plurality of sampling switched capacitors when connected to the central node during the gain phase.

A pipelined analog-to-digital converter (ADC) and a residue amplifier used in the ADC. An ADC includes a capacitive digital-to-analog converter (CDAC), a residue amplifier, and a switched capacitor circuit. The residue amplifier is coupled to the CDAC. The residue amplifier includes a first complementary transistor pair and a first tail current circuit. The first complementary transistor pair is coupled to a first output of the CDAC, and includes a high-side transistor and a low-side transistor. The first tail current circuit is coupled to the high side transistor. The switched capacitor circuit is coupled to inputs of the CDAC and to the first tail current circuit. The switched capacitor circuit is configured to generate a voltage to bias the first tail current circuit with compensation for common mode voltage at the inputs of the CDAC.

A pipelined analog-to-digital converter (ADC) using a multiplying digital-to-analog converter (MDAC) and two sub-range analog-to-digital converters (sub-range ADCs) is disclosed. The MDAC samples an analog input and performs multiplication on the sampled analog input based on control bits. The first sub-range ADC provides the MDAC with the control bits. The second sub-range ADC is coupled to the MDAC for conversion of a multiplied signal output from the MDAC. The first sub-range ADC samples the analog input to generate the control bits for the MDAC as well as pre-estimated bits for the second sub-range ADC. The second sub-range ADC operates based on the pre-estimated bits and thereby a first section of digital bits are generated by the second sub-range ADC. A second section of digital bits are provided by the first sub-range ADC. The first and second sections of digital bits represent the analog input

Pipelined analog-to-digital converters (ADCs) include a flash ADC that reduces noise tones in power supply current drawn by the flash ADC. A pipelined analog-to-digital converter (ADC) includes a flash ADC and error correction circuitry coupled to the flash ADC. The flash ADC includes a plurality of latched comparators and a plurality of driver circuits. Each of the latched comparators includes an inverting output and a non-inverting output. Each of the driver circuits is coupled to one of the latched comparators, and includes an input terminal and an output terminal. In a first subset of the driver circuits the input terminal is coupled to the inverting output of one of the latched comparators. In a second subset of the driver circuits the input terminal is coupled to the non-inverting output of one of the latched comparators.

A pipelined analog-to-digital converter has an analog signal input. A first input sample-and-hold circuit is connected to the analog signal input. An amplifier is connected to an output of the first input sample-and-hold circuit. A second input sample-and-hold circuit has an input connected to the analog signal input in parallel to the first input sample-and-hold circuit. An AD/DA conversion path is connected to an output of the second input sample-and-hold circuit. A first output sample-and-hold circuit has an input connected to an output of the amplifier. A second output sample-and-hold circuit has an input connected to the output of the amplifier. The amplifier, the first output sample-and-hold circuit, the second input sample-and-hold circuit, and the AD/DA conversion path are part of a converter stage and outputs of the converter stage are inputs to a following converter stage.