摘要:
Multiplying digital-to-analog converters (MDACs), which are generally employed in pipelined analog-to-digital converters (ADCs), can have a settling error associated with the MDAC amplifier. Here, a circuit is provided that includes additional amplifiers and a capacitor network that compensates for this settling error. Thus, a more accurate pipelined ADC can now be produced.
摘要:
An offset correction circuit examines a residue signal of a stage of a pipeline analog to digital converter (ADC) to determine whether a parameter which could cause offset error, needs to be adjusted. In an embodiment, the parameter is adjusted until a maximum range of the residue signal equals an expected range. In the described examples, the adjusted parameters include timing offset error (when components of an ADC sample the input signal at different time instances) and a voltage offset error (the threshold voltage at which a sub-ADC in a stage the generated sub-code changes to a next value).
摘要:
An aspect of the present invention reduces droop in the reference signal provided to ADCs. A compensation resistor of appropriate resistance value is provided in the path of the reference signal to minimize the droop.
摘要:
Traditionally, input source follower buffers for analog-to-digital converters (ADCs) lacked sufficiently high linearity. This was due in part to source follower buffers having to drive external capacitive loads by generally providing a signal current to the capacitive load. Here, a buffer is provided that includes a source follower buffer and other biasing circuitry (which provided the signal current). Thus, the overall linearity of the input circuitry (namely, the input buffer) is improved.
摘要:
An apparatus is provided. The apparatus comprises a sample switch, a sampling capacitor, an amplifier, feedback branches, a second hold switch, an N-bit converter pair, a third hold switch, and an M-bit converter pair. The sample receives an input signal and is actuated by a sample signal. The sampling capacitor is coupled to the sample switch. The amplifier has a first input terminal that is coupled to the sampling capacitor. The feedback branches are coupled between the output terminal of the amplifier and the first input terminal of the amplifier, with each feedback branch including a feedback capacitor, and a first hold switch that is coupled to the feedback capacitor. The second hold switch is coupled to the sampling switch. The N-bit converter pair is coupled to the sampling switch and to the second hold switch. The third hold switch is coupled to at least one of the feedback branches, and the M-bit converter pair is coupled to the output terminal of the amplifier and to the third hold switch.
摘要:
An apparatus is provided. The apparatus comprises a sample switch, a sampling capacitor, an amplifier, feedback branches, a second hold switch, an N-bit converter pair, a third hold switch, and an M-bit converter pair. The sample receives an input signal and is actuated by a sample signal. The sampling capacitor is coupled to the sample switch. The amplifier has a first input terminal that is coupled to the sampling capacitor. The feedback branches are coupled between the output terminal of the amplifier and the first input terminal of the amplifier, with each feedback branch including a feedback capacitor, and a first hold switch that is coupled to the feedback capacitor. The second hold switch is coupled to the sampling switch. The N-bit converter pair is coupled to the sampling switch and to the second hold switch. The third hold switch is coupled to at least one of the feedback branches, and the M-bit converter pair is coupled to the output terminal of the amplifier and to the third hold switch.
摘要:
An offset correction circuit examines a residue signal of a stage of a pipeline analog to digital converter (ADC) to determine whether a parameter which could cause offset error, needs to be adjusted. In an embodiment, the parameter is adjusted until a maximum range of the residue signal equals an expected range. In the described examples, the adjusted parameters include timing offset error (when components of an ADC sample the input signal at different time instances) and a voltage offset error (the threshold voltage at which a sub-ADC in a stage the generated sub-code changes to a next value).
摘要:
A switched capacitor environment in which a feedback capacitor of a stage is flipped to be used as a sampling capacitor of the next stage. Due to such use of the feedback capacitor, the noise introduced by the stages is substantially reduced. Such switched capacitors can be used in analog to digital converters (ADC).
摘要:
A resistor (or a component with impedance that does not change) is provided across the output of an amplifier, which minimizes the changes in the amplification factor of an amplification circuit during operation.
摘要:
Using an operational amplifier with a low gain in a closed loop amplifier circuit, and correcting for errors (i.e., deviation from the output of an ideal closed loop amplifier using an operational amplifier with infinite gain) that would result from the use of the operational amplifier with low gain. In an embodiment implemented in relation to an analog to digital converter (ADC), a mathematical operation is performed on the digital code(s) generated by the ADC to generate a corrected code corresponding to an analog sample.