Patent classifications
H03M7/165
SELF-ORGANIZED ENCODER ARCHITECTURES INCLUDING BLIND INPUT SWAPPING SUPPORT
Some embodiments include an encoder to convert a thermometer code into a binary code output information or a Gray code output information. The encoder supports blind input swapping, such that it provides correct output information without prior knowledge of the input swapping. Some embodiments also include a truth table that has additional rows to describe output information when input information at inputs of the encoder is swapped. The encoder includes symmetrical logic functions with respect to information at its inputs as building blocks.
DWA CIRCUIT AND DA CONVERSION APPARATUS
A DWA circuit includes: a thermometer conversion unit configured to convert an input digital signal into a thermometer code; a shift amount storage unit configured to store a shift amount; a shift unit configured to cyclically shift the thermometer code; an arrangement conversion unit configured to supply, to an analog output circuit, an output control code obtained by converting a bit arrangement of a shifted code; and an update unit configured to update the shift amount, in which the shifted code includes a plurality of unconverted bit fields, the output control code includes a plurality of converted bit fields, and the arrangement conversion unit is configured to perform arrangement conversions on a plurality of bits having a same position in a bit field in the plurality of unconverted bit fields, to arrange the plurality of bits in a same converted bit field among the plurality of converted bit fields.
TRANSFORMATION APPARATUS, ENCODING APPARATUS, DECODING APPARATUS, TRANSFORMATION METHOD, ENCODING METHOD, DECODING METHOD, AND PROGRAM
Provided is a technique for converting an integer value sequence for encoding/decoding which allows an integer value sequence having a distribution including small values other than a zero value and greatly biased to small values to be encoded with a small average bit number. Provided are: a unary coding unit which subjects an input sequence of non-negative integer values to unary coding to obtain a unary code sequence; a bit reversing unit which replaces a bit value ‘0’ with a bit value ‘1’ and a bit value ‘1’ with a bit value ‘0’ in the bits in the unary code sequence to obtain a replaced code sequence; and a unary decoding unit which subjects the replaced code sequence to unary decoding to obtain a sequence of non-negative integer values.
Analog to digital converter including differential VCO
An analog to digital converter is provided. The analog to digital converter includes: an arithmetic operator combining an analog input signal with a feedback signal; a loop filter filtering an output signal of the arithmetic operator; a quantizer quantizing an output signal of the loop filter to output a digital signal; and a feedback converting the digital signal to output a feedback signal, in which the quantizer includes: a plurality of VCOs each receiving a positive output signal and a negative output signal of the loop filter and outputting VCO signals; a plurality of samplers receiving the VCO signals output from the plurality of VCOs, respectively and outputting sampled signals; and a phase detector detecting a phase difference in the sampled signals output from the plurality of samplers, respectively, to detect a phase difference in two VCO signals output from the plurality of VCOs, respectively.
Phase rotator non-linearity reduction
A phase rotator receives control signals and thermometer coded signals that specifies the phase of an output signal. The phase rotator may be used, for example, by a clock and data recovery (CDR) circuit to continually rotate the phase of a clock to compensate for phase/frequency mismatches between received data and the clock. The control signals determine the phase quadrant (i.e., 0°-90°, 90°-180°, etc.) of the output signal. The thermometer coded signals determine the phase of the output signal within a quadrant by steering a set of bias currents between two or more nodes. The set of bias currents are selected to reduce the non-linearity between the thermometer coded value and the phase of the output signal.
Anti-aliasing techniques for time-to-digital converters
Systems, apparatuses, and methods for implementing an anti-aliasing technique for a time-to-digital converter are described. A pulse generator generates a pulse with a width that is representative of a voltage level of a supply voltage. A buffer chain receives the pulse from the pulse generator. A first sum is calculated by adding together a number of one bits in a first portion of the buffer chain. Also, a second sum is calculated by adding together a number of one bits in a second portion of the buffer chain. Then, a third sum is calculated by adding the first sum to the second sum if the first sum is saturated. Otherwise, the third sum is equal to the first sum if the first sum is not saturated. The third sum is used as a representation of the voltage level of the supply voltage.
TIME TO DIGITAL CIRCUITRY WITH ERROR PROTECTION SCHEME
A time to digital circuit may provide a time measurement of an event, or a time measurement of a duration between multiple events. Various electronic devices may include one or more time to digital circuits. A time to digital circuit may include circuitry to use Thermometer Code for measuring the duration of the time. For example, the time to digital circuit may generate alternating signals using a ring oscillator when receiving an indication of an event. Moreover, the time to digital circuit may convert the alternating signals to a consistent signal with only one transition between high and low signals in multiple consecutive signals. Furthermore, the time to digital circuit may correct erroneous signal values of the consistent signals when multiple transitions between high and low signals in multiple consecutive signals occurs.
DIGITAL-TO-ANALOG CONVERSION CIRCUIT AND RECEIVER INCLUDING THE SAME
A digital-to-analog conversion circuit includes a first digital-to-analog converter (DAC) and a second DAC. The first DAC includes a first current generation circuit (CGC) and a first current-to-voltage converter. The first CGC generates a first current based on a first digital code received through a first terminal to provide the first current to an output node. The second DAC includes a second CGC and a second current-to-voltage converter. The second CGC generates a second current based on a second digital code received through a second input terminal to provide the second current to the output node. The first current-to-voltage converter and the second current-to-voltage converter convert a sum of the first current and the second current to a an analog voltage corresponding to a sum of the first digital code and the second digital code, and output the analog voltage at the output node.
DOUBLE DATA RATE (DDR) QUAD SWITCHED MULTIBIT DIGITAL TO ANALOG CONVERTER AND CONTINUOUS TIME SIGMA-DELTA MODULATOR
A quad signal generator circuit generates four 2.sup.N-1 bit control signals in response to a 2.sup.N-1 bit thermometer coded signal. A digital-to-analog converter (DAC) circuit has 2.sup.N-1 unit DAC elements, with each unit DAC element including four switching circuits controlled by corresponding bits of the four 2.sup.N-1 bit control signals. Outputs of the 2.sup.N-1 unit DAC elements are summed to generate an analog output signal. The quad signal generator circuit controls a time delay applied to clock signals relative to the 2.sup.N-1 bit thermometer coded signal and a time delay applied to the 2.sup.N-1 bit thermometer coded signal relative to the delayed clock signals in logically generating the four 2.sup.N-1 bit control signals. The analog output signal may be a feedback signal in a sigma-delta analog-to-digital converter (ADC) circuit that includes a multi-bit quantization circuit operating to quantize a filtered loop signal to generate the 2.sup.N-1 bit thermometer coded signal.
TECHNIQUES TO EXTERNALLY CONTROL AMPLIFIER GAIN
Techniques for setting a gain of an amplifier circuit in which the external resistor of the amplifier circuit is used to determine an internal gain setting to select. A voltage across the external resistor can be compared to an on-chip reference, and then used to program the desired gain. The techniques can mitigate or eliminate the need for a high-accuracy external resistor and can allow substantial improvements in initial gain accuracy and gain drift for existing boards and/or systems with only a bill of material change.