摘要:
An analog/digital converter for converting an analog signal to a digital output code includes a local digital analog converter including a segmented array. The segmented array includes upper and lower segments of conversion elements selectively operable by respective digital command codes for respectively varying, according to binary weighted contributions, the voltages of first and second common nodes and the voltage of a second common node. A logic unit generates the digital command codes for controlling the local digital/analog converter according to a successive approximation technique for producing the digital output code. The converter includes a redistributor for modifying the command codes for redistributing the modified command codes between the lower segment and the upper segment, while making use of at least one auxiliary conversion element provided in the upper segment.
摘要:
The described analog-digital converter comprises quantization means having an input for receiving an analog quantity to be converted, a register having an output for providing a digital quantity corresponding to the analog quantity, a timing pulse generator and logic means connected to the quantization means, the register and the timing pulse generator and capable of responding to a conversion request signal by activating the quantization means in such a manner as to make them carry out predetermined operations timed by the timing pulses and load into the register the digital quantity to be provided at the output. With a view to permitting the converter to function even when a system clock is not available, the timing pulse generator, which is incorporated in the integrated circuit that comprises the rest of the converter, comprises an oscillator capable of being started/stopped by a binary signal applied to its activation input and the logic means are capable of generating a stop signal of the oscillator and comprise means for generating the binary signal to be applied to the activation input of the oscillator. This signal assumes a first or a second binary state corresponding, respectively, to activation and deactivation of the oscillator in response to, respectively, the conversion request signal and the stop signal of the oscillator.
摘要:
The described analog-digital converter comprises quantization means having an input for receiving an analog quantity to be converted, a register having an output for providing a digital quantity corresponding to the analog quantity, a timing pulse generator and logic means connected to the quantization means, the register and the timing pulse generator and capable of responding to a conversion request signal by activating the quantization means in such a manner as to make them carry out predetermined operations timed by the timing pulses and load into the register the digital quantity to be provided at the output. With a view to permitting the converter to function even when a system clock is not available, the timing pulse generator, which is incorporated in the integrated circuit that comprises the rest of the converter, comprises an oscillator capable of being started/stopped by a binary signal applied to its activation input and the logic means are capable of generating a stop signal of the oscillator and comprise means for generating the binary signal to be applied to the activation input of the oscillator. This signal assumes a first or a second binary state corresponding, respectively, to activation and deactivation of the oscillator in response to, respectively, the conversion request signal and the stop signal of the oscillator.
摘要:
A method of operating an SAR-type analog-to-digital converter to match the dynamic range of an input voltage signal to be converted with the full scale range of the converter, the converter including at least one array of binary weighted capacitors. The method includes the step of obtaining a digital gain code that represents the ratio between the full scale range and the dynamic range of the voltage signal to be converted, applying the voltage signal to be converted to the capacitor array so as to charge with the voltage signal to be converted only those array capacitors having the same binary weights as the bits of the gain code that have a selected binary value, and selectively coupling the capacitors of the array to one of a first and second predetermined reference voltage terminals according to an SAR technique, to obtain an output digital code corresponding to the input voltage signal.
摘要:
An analog/digital converter for converting an analog signal to a digital output code includes a local digital analog converter including a segmented array. The segmented array includes upper and lower segments of conversion elements selectively operable by respective digital command codes for respectively varying, according to binary weighted contributions, the voltages of first and second common nodes and the voltage of a second common node. A logic unit generates the digital command codes for controlling the local digital/analog converter according to a successive approximation technique for producing the digital output code. The converter includes a redistributor for modifying the command codes for redistributing the modified command codes between the lower segment and the upper segment, while making use of at least one auxiliary conversion element provided in the upper segment.
摘要:
A circuit for selectively converting at least one analog signal into corresponding digital codes. The circuit includes a management block having a plurality of inputs, each adapted for receiving a respective request signal carrying a request to convert the at least one analog signal. The management block is adapted to assign a priority level to the request signals based upon the input where the request signals are received, and is further operative to select one of the request signals based upon the assigned priority level and output a conversion start-up signal corresponding to the selected request signal. The circuit has a conversion block for receiving east one analog signal input and is connected to the management block to receive the conversion start-up signal as input, and start up conversion of the at least one analog signal.
摘要:
The described converter comprises switched-capacitor quantization means for receiving an analog quantity to be converted, a register for a digital quantity corresponding to the analog quantity, a timing pulse generator and logic means capable of responding to a conversion request signal by activating the quantization means in such a way that they will carry out predetermined operations timed by the timing pulses and load in the register the digital quantity to be furnished as output. With a view to saving electric energy during the conversion and reducing the noise induced by the generator, the generator comprises means for modifying the duration and/or the frequency of the timing pulses in response to regulation signals emitted by the logic means. Also described is a method of using the converter that comprises the following phases: loading of the analog quantity in the quantization means, memorization of the loaded analog quantity and identification in the course of successive attempts in accordance with SAR technique of the bits of the digital code corresponding to the analog quantity to be converted. The duration and/or the frequency of the timing pulses are modified during at least one of the phases indicated above in response to regulation signals emitted by the logic means.
摘要:
A system includes analog supply circuitry providing first and second analog potentials. A switch module assumes first or second states to enable and inhibit transfer of an analog electrical signal from a source module to a user module based upon a driving electrical signal. A driving device drives, based upon the driving electrical signal, a control terminal of the switch module, allowing the switch module to assume the first or second state. The driving device allows the switch module to make a first driving transition from the first state to the second state, and a second driving transition from the second state to the first state. The driving device alternately connects the control terminal to a first reference potential, during the first state, and to a second reference potential, during the second state. The driving device connects the control terminal of the switch module to a third reference potential electrically distinct from the first and the second analog potentials, during each of the time intervals associated to the first or second driving transitions of the switch module.
摘要:
An electrical circuit for conversion from differential to single-ended includes a differential amplifier stage and first and second buffer circuits. The differential amplifier stage includes a first and a second input; and a first and a different second charging circuit that can be operatively coupled, respectively, with an output of the conversion circuit and with an auxiliary output. Each of the first and second buffer circuits is functionally arranged between one of said outputs and between one of said charging circuits. The buffer circuits being configured so as to substantially equalize relative impedances seen towards said outputs.
摘要:
A current steering digital-analog converter for converting a digital code into an analog signal, the converter including a substrate of semiconductor material, an array of current generators integrated in the substrate, a common summation node and switches controllable on the basis of the digital code for connecting and disconnecting the current generators to and from the common summation node. The current generators are adapted to provide the common summation node with currents having a multiple value according to a power of two compared to a unit current value provided to the summation node by a current generator of the array of generators. The current generator is divided into a base number of modular current generation elements in parallel to one another at least equal to two.