An analog-to-digital conversion device includes: a switch connected to input units through signal lines to receive external voltages selecting and outputting one external voltage; an S/H circuit holding a voltage corresponding to an output of the switch; a converter performing AD conversion based on the voltage; and a controller determining the external voltage selected by the switch and performing a disconnection determination whether a disconnection occurs in the signal line. In the disconnection determination, the controller controls the switch to select a reference voltage different from the external voltage before controlling the switch to select the external voltage to be determined, and performs the disconnection determination based on a voltage difference between the reference voltage and the external voltage after controlling the switch to select the external voltage.

In some examples, a device includes an analog-to-digital converter (ADC) configured to receive an analog signal and output digital codes based on values of the analog signal. The device also includes a plurality of counters, where each counter of the plurality of counters is configured to increment in response to a respective digital code outputted by the ADC.

Described herein are apparatus and methods for low speed characterization of a high-speed signal. A circuit includes a sub-sampling circuit configured to sub-sample a high-speed signal received from a device, a reconstruction loop circuit configured to reconstruct a low-speed signal from the sub-sampled high-speed signal, a low pass filter configured to filter the reconstructed low-speed signal, a discrete time low pass filter configured to mitigate skew rate requirements of the filtered low-speed signal for a digitization circuit, a continuous time low pass filter configured to smooth the skew rate mitigated low-speed signal and the digitization circuit is configured to generate a digital representation of the smoothed low-speed signal for characterization by a characterization device, and shape a noise associated with the smoothed low-speed signal outside a frequency range of interest of the smoothed low-speed signal.

A method is described that is performed by a calibration system. The method includes determining a set of perturbation values for configuring an analog-to-digital converter of the calibration system; generating a set of digital test values for determining the accuracy of the analog-to-digital converter; and applying the set of perturbation values to the set of digital test values to generate a set of modified test values, wherein the set of perturbation values are digital values that are applied to the set of digital test values in the digital domain.

In some examples, a device includes an analog-to-digital converter (ADC) configured to receive an analog signal and output digital codes based on values of the analog signal. The device also includes a plurality of counters, where each counter of the plurality of counters is configured to increment in response to a respective digital code outputted by the ADC.

A comparator offset calibration system having a comparator offset evaluator and a switched-capacitor network is disclosed, which is in an analog and digital dual domain structure. The comparator offset evaluator receives digital data from an analog-to-digital conversion module, evaluates an offset of a comparator of the analog-to-digital conversion module based on the received digital data, and outputs an evaluated result. The switched-capacitor network processes the evaluated result to generate a control signal. The analog-to-digital conversion module adjusts the offset of the comparator according to the control signal.

A switching circuit for checking an analog input circuit of an A/D converter is shown. The switching circuit comprises the analog circuit and a comparator circuit. The analog input circuit is configured to generate a first derived signal S1 and a second derived signal S2 from an analog input signal SE of the analog input circuit. The first derived signal S1 and the second derived signal S2 are input signals for the comparator circuit, but only the first derived signal S1 is an input signal for the A/D converter. The comparator circuit is configured to check whether a deviation of the derived signals S1, S2 from each other lies within a tolerance range TOL and to output an output signal SA depending on the check, which may be further evaluated.

An analog-to-digital conversion device includes: a switch connected to input units through signal lines to receive external voltages selecting and outputting one external voltage; an S/H circuit holding a voltage corresponding to an output of the switch; a converter performing AD conversion based on the voltage; and a controller determining the external voltage selected by the switch and performing a disconnection determination whether a disconnection occurs in the signal line. In the disconnection determination, the controller controls the switch to select a reference voltage different from the external voltage before controlling the switch to select the external voltage to be determined, and performs the disconnection determination based on a voltage difference between the reference voltage and the external voltage after controlling the switch to select the external voltage.

A constant current source, a stable time base and a capacitor are used to self-check operation of an analog-to-digital convertor (ADC) by charging the capacitor for a pre-determined amount of time to produce a voltage thereon. This voltage will be proportional to the amount of time that the capacitor was charged. Multiple points on the ADC transfer function can be verified in this self-check procedure simply by varying the amount of time for charging of the capacitor. Relative accuracy among test points may then be easily obtained. Absolute accuracy may be obtained by using an accurate clock reference for the time base, a known current source and capacitor value.

A method and apparatus for characterizing an A/D converter are provided. The A/D converter is configured to convert an input signal into a digital output signal. The method and apparatus may provide: applying an input signal to the A/D converter that in a first phase at least includes a gradient of a rising exponential function with Euler's number as the base, and in a further phase has a profile of a falling exponential function with Euler's number as the base, integrating a digital output signal associated with the A/D converter during the first phase to provide a first sum, integrating the digital output signal associated with the A/D converter during the further phase to provide a second sum, and calculating from the first sum and the second sum at least a gain error of the A/D converter and/or a zero point error of the A/D converter.