Abstract:
A pseudo-differential switched-capacitor circuit using integrator-based common-mode stabilization technique is disclosed. A pseudo-differential switched-capacitor circuit with the differential floating sampling (DFS) technique has a common-mode gain value of one (1). An integrator is electrically coupled to the differential positive/negative outputs of the DFS circuit, and the integrator feeds back integrator output to the DFS circuit by detecting common-mode voltage disturbance at the differential positive output (Vout+) and negative output (Vout−), thereby stabilizing output common-mode level of the differential positive output (Vout+) and negative output (Vout−) at a desirable level.
Abstract:
A metal-oxide-metal (MOM) capacitor able to reduce area of capacitor arrays is revealed. The MOM capacitor mainly includes at least three parallel conducting layers. Each parallel conducting layer consists of a first conductive plate, a second conductive plate disposed around the first conductive plate. There is a preset distance between the first conductive plate and the second conductive plate. The first conductive plates are electrically connected by at least one first via while the second conductive plates are electrically connected by at least one second via. Thereby, while being applied to capacitor arrays, the second conductive plates of the two adjacent MOM capacitors are connected together and shared with each other, so as to significantly reduce area of the capacitor array, improve circuit density and further optimize the layout efficiency of the chip design.
Abstract:
A SAR ADC, used for converting an analog input into an N-bit digital output in a conversion phase, includes: three comparators, each two capacitor sub-arrays, coupled to the three comparators respectively, wherein the two capacitor sub-arrays are used for sampling the analog input and providing two inputs for the corresponding comparator; and an SAR logic, coupled to the three comparators and the three capacitor arrays, for, in each conversion sub-phase, coupling two selected capacitors of each capacitor sub-array to a set of determined reference levels, coupling two capacitors, which were selected in a preceding conversion sub-phase, of each capacitor sub-array to a set of adjusted reference levels obtained based on a set of data outputted from the three comparators in a preceding conversion sub-phase, and then generating two bits of the N-bit digital output by encoding a set of data outputted from the three comparators.
Abstract:
A capacitance mismatch calibrating method for a successive approximation register ADC which includes at least one array of capacitors is provided. The method includes the following steps: firstly, at least two compensating capacitors are configured. A capacitor from the array of capacitors is selected as a capacitor-under-test. Then, the terminal voltages on the terminals of the array of capacitors and on the terminals of the compensating capacitors are determined. A first comparison voltage is outputted based on the determined terminal voltages. Afterwards, a sequence of comparisons is controlled based on the first comparison voltage and a second comparison voltage to output a sequence of corresponding digital bits. Finally, a calibration value is calculated to calibrate the value of a capacitor-under-test according to the digital bits.
Abstract:
A pseudo-differential switched-capacitor circuit using integrator-based common-mode stabilization technique is disclosed. A pseudo-differential switched-capacitor circuit with the differential floating sampling (DFS) technique has a common-mode gain value of one (1). An integrator is electrically coupled to the differential positive/negative outputs of the DFS circuit, and the integrator feeds back integrator output to the DFS circuit by detecting common-mode voltage disturbance at the differential positive output (Vout+) and negative output (Vout−), thereby stabilizing output common-mode level of the differential positive output (Vout+) and negative output (Vout−) at a desirable level.
Abstract:
A pseudo-differential switched-capacitor circuit, which can be applied to various signal processing circuits, employs a floating sampling technique and an integrator feedback loop for isolating a common mode voltage disturbance and restraining a charge injection effect. The pseudo-differential switched-capacitor circuit includes a differential floating sampling circuit that has a pseudo-differential architecture, and an integrator for reducing the charge injection effect within the differential floating sampling circuit.
Abstract:
The present invention is directed to a multiplying digital-to-analog converter (MDAC) and its method. First ends of capacitors are electrically coupled to an inverting input node of an amplifier, wherein two of the capacitors are alternatively configured as a feedback capacitor. Each capacitor is composed of at least two sub-capacitors. Second ends of capacitors are electrically coupled to an input signal via a number of sampling switches, and the second ends of the capacitors are electrically coupled to DAC voltages respectively via a number of amplifying switches. A sorting circuit is configured to sort the sub-capacitors, wherein the sorted sub-capacitors are then paired in a manner such that variance of mismatch among the sub-capacitors is thus averaged.
Abstract:
An analog-to-digital converter (ADC) for pipelined ADCs or cyclic ADCs is disclosed. The ADC includes at least one pair of two stages connected in series, and the two stages have different bits of resolution. An amplifier is shared by the pair of two stages such that the two stages operate in an interleaved manner. Accordingly, this stage-resolution scalable opamp-sharing technique is adaptable for pipelined ADC or cyclic ADC, which substantially reduces power consumption and increases operating speed.
Abstract:
A method of fabricating a dielectric layer is described. A twelve-inch wafer having at least three metallic layers thereon is provided. A dielectric layer is formed over the twelve-inch wafer by performing a high-density plasma process. The high-density plasma process includes applying a total bias radio frequency (RF) power and a total source radio frequency (RF) power. Furthermore, the ratio between the total bias RF power and the total source RF power is about 0.7 to 2.5.
Abstract:
A method for operating a SAR assisted pipelined ADC includes enabling a SAR ADC in a current stage circuit for converting an input analog voltage into a digital code during a first time interval, resetting an operational amplifier of an MDAC in the current stage circuit during the first time interval, maintaining the SAR ADC of the current stage circuit in an enabled state for outputting during a second time interval, and enabling the MDAC in the current stage circuit during the second time interval. The method also includes enabling the SAR ADC in the current stage circuit for sampling during a third time interval and connecting the output terminal of the MDAC in the current stage circuit to the input terminal of the next stage circuit during the third time interval. The first, second, and third time intervals are continuous and do not overlap each other.