Accuracy bootstrapping

An analog-to-digital converter implemented using accuracy bootstrapping for calibration, comprising:

• a plurality of analog-to-digital converter stages coupled together;
• switching circuitry for reconfiguring said plurality of converter stages so that any one can be first in a serial chain, followed by the remainder of said plurality of converter stages;
• control circuitry operable to cause any one of said stages to output signals indicative of values of one or more of the fixed elements within said stage;
• sequencing circuity operable for causing a first stage in the serial configuration of converter stages to output signals indicative of the value of fixed components within it, and causing the resulting output to be input to the remaining stages in said serial configuration of stages, the remaining stages taking a measurement indicative of the value of the fixed components within said first stage.

An integrated circuit implementing an analog-to-digital converter, comprising:

• a plurality of analog-to-digital converter stages, each having a digital code as an output, each having an analog output, serially coupled together;
• switching circuitry for reconfiguring said plurality of converter stages so that any one can be first in a serial chain, followed by the remainder of said plurality of converter stages;
• control circuitry operable to cause any one of said stages to selectively output signals indicative of the values of one or more fixed elements within said stage;
• storage circuitry for storing said digital codes, and for mapping said digital codes onto adjustable coefficients;
• computing circuitry for computing said adjustable coefficients and storing new values in said storage circuitry;
• sequencing circuitry coupled to said control, storage and computing circuitry and operable for causing a first stage in the serial configuration of converter stages to output the value of fixed components within it, causing the resulting measurement made on the said value to be stored, causing the said stored measurement to be used for computing a new adjustable coefficient, and operable for storing said new adjustable coefficient.

A method for implementing a system having improved accuracy and fast calibration, comprising the steps of:

• providing a series of stages, each implementing a transfer function using fixed and adjustable elements, the series of stages coupled together and implementing a desired system transfer function;
• providing control circuitry operable to reconfigure the series of stages, so that any one stage may be selectively placed first in the series, and the remaining stages may be placed after the one stage;
• providing storage circuitry operable to store adjustable parameters for each of said series of stages;
• providing circuitry operable to cause any one of said stages to output signals indicative of the value of fixed elements within said one of said stages;
• providing computation circuitry operable to compute new values for the adjustable elements within any one of said stages;
• configuring the series of said stages so that any one selected stage is placed first, and the remaining stages follow the said one selected stage;
• controlling the output of said selected stage so that the remaining series of stages measure the output indicative of the value of one of the fixed elements of said selected stage;
• storing the measurement of the fixed element value output by the selected stage;
• again controlling the output of the selected stage and measuring until measurements indicative of all of the fixed values have been stored;
• computing new adjustable element values for the adjustable elements in the selected stage, and updating the adjustable elements by storing those values;
• replacing the selected stage with another one of said stages, and repeating the last four stops;
• continuing the last five steps until the adjustable elements of all stages have been updated.

A method for implementing an analog-to-digital converter having improved accuracy and fast calibration, comprising the stops of:

• providing a plurality of analog-to-digital converter stages, each having a transfer function, each having a digital code as an output, coupled together to implement a system transfer function;
• providing switching circuitry for reconfiguring said plurality of converter stages so that any one can be first in a chain, followed by the remainder of said plurality of converter stages;
• providing control circuitry operable to cause any one of said stages to output signals indicative of the transfer function within said stage;
• providing sequencing circuity coupled to said converter stages for reconfiguring said converter stages;
• configuring said converter stages to select one of said stages as the first stage, the remaining stages coupled to said first stage and each other;
• causing the said first stage to output one or more values indicative of the characteristics of the transfer function within it;
• using the remaining stages to measure the transfer function characteristics of said first stage;
• selecting another stage to be the first stage;
• reconfiguring the configuration of the converter stages of the system, and repeating the last three steps until the characteristics of the transfer function of each of said plurality of converter stages have been measured.

A system physically realizing a transfer function and having improved accuracy and fast calibration, comprising:

• a plurality of stages, each having one or more transfer functions defining a predetermined relationship between inputs and outputs, said plurality of stages coupled together to implement the system transfer function;
• control logic for selectively reconfiguring said stages so that the output of any one of said stages is coupled to the input of at least one other of said stages;
• and
• operable to allow any one of said stages to be configured as the first stage in a sequence made up of at least one other of said stages, the first stage outputting responses in response to selective excitation at its input, the remaining stages capturing said output responses from said first stage as a measurement of one or more of the transfer functions of said first stage.

An analog-to-digital converter implemented using accuracy bootstrapping for calibration, comprising:

• a plurality of analog-to-digital converter stages coupled together;
• switching circuitry for reconfiguring said plurality of converter stages so that any one can be first in a serial chain, followed by the remainder of said converter stages;
• control circuitry operable to cause any one of said stages to output signals indicative of the values of the fixed elements within said stage;
• and
• sequencing circuity operable for causing a first stage in the serial configuration of converter stages to output signals indicative of the value of fixed components within it, the remaining stages taking a measurement of said output signals which is indicative of the value of the fixed components within said first stage.

A method for implementing a system having improved accuracy and fast calibration, comprising the steps of:

• providing a series of stages, each implementing a transfer function using fixed and adjustable elements, the series of stages coupled to implement a desired system transfer function;
• providing control circuitry operable to reconfigure the series of stages, so that any one stage may be selectively placed first in the series, the remaining stages following;
• providing storage circuitry operable to store adjustable parameters for said series of stages;
• providing circuitry operable to cause one or more of said stages to output signals indicative of the value of said fixed elements within said stages;
• configuring the series of said stages so that any one selected stage is placed first, and the remaining stages follow the said one selected stage;
• controlling the output of said selected stage so that the remaining series of stages measure the output indicative of the value of one or more of the fixed elements of said selected stage;
• storing the measurement of the fixed element values output by the selected stage;
• computing new adjustable element values for the adjustable elements in the selected stage, and updating the adjustable elements values;
• replacing the selected stage with another one of said stages, and repeating the last four steps;
• and
• continuing the last five steps until the adjustable elements of all stages have been updated.