Patent classifications
H03M1/0604
Interleaving ADC error correction methods for Ethernet PHY
A receiver circuit includes an interleaved ADC, a first delay circuit, a second delay circuit, a first processing channel, a second processing channel, and an interleaving ADC timing error detector circuit. The interleaved ADC includes a first ADC and a second ADC in parallel. The first delay circuit delays a first clock signal provided to the first ADC. The second delay circuit delays a second clock signal provided to the second ADC. The first processing channel processes data samples provided by the first ADC, and includes a first slicer. The second processing channel processes data samples provided by the second ADC, and includes a second slicer. The interleaving ADC timing error detector circuit controls delay of the first delay circuit and the second delay circuit based on an output signal of the first slicer, and an output signal or an input signal of the second slicer.
ANALOG-TO-DIGITAL CONVERTER
An analog-to-digital converter (ADC) includes a coarse ADC that receives an analog input voltage, generates a first digital signal based on the analog input voltage using a successive approximation register (SAR) method, and outputs a residual voltage remaining after the first digital signal is generated. The ADC further includes an amplifier that receives the residual voltage and a test voltage, generates a residual current by amplifying the residual voltage by a predetermined gain, and generates a test current by amplifying the test voltage by the gain. The ADC further includes a fine ADC that receives the residual current and generates a second digital signal based on the residual current using the SAR method, and an auxiliary path that receives the test current and generates a gain correction signal based on the test current. The gain of the amplifier is adjusted based on the gain correction signal.
Leakage compensation for analog decoded thermometric digital-to-analog converter (DAC)
A method of converting an N-bit digital code into analog output currents includes switchably connecting a first number of PN junctions to a positive output terminal and a second number of PN junctions to a negative output terminal based on the N-bit digital code; and switchably connecting a plurality of additional PN junctions to the positive output terminal and the negative output terminal based on the N-bit digital code, including connecting a first number of additional PN junctions to the positive output terminal based on the N-bit digital code and connecting a second number of additional PN junctions to the negative output terminal based on the N-bit digital code such that a first sum of the first number of PN junctions and the first number of additional PN junctions is equal to a second sum of the second number of PN junctions and the second number of additional PN junctions.
LOW INTEGRAL NON-LINEARITY DIGITAL-TO-TIME CONVERTER FOR FRACTIONAL-N PLLS
An apparatus includes a first digital-to-time converter (DTC) and a second DTC. The first DTC includes a sequence of delay stages. Each of the delay stages adds a delay to an input signal based on a control signal. Each delay stage includes a comparator and a capacitor coupled to an input of the comparator and to ground. The second DTC is coupled in parallel to the first DTC. The second DTC adds a delay to the input signal based on a complement of the control signal.
Error extraction method for foreground digital correction of pipeline analog-to-digital converter
An error extraction method for foreground digital correction of a pipeline analog-to-digital converter including: acquiring a transmission curve of a pipeline analog-to-digital converter, and controlling an input signal to be within a sub-segment 0 of the transmission curve; during extraction of error information of an ith pipeline stage, setting a magnitude of the input signal according to Formula (I); locking the outputs of all previous-stage comparators in the i.sup.th pipeline stage of the pipeline analog-to-digital converter; and completing, according to original output code of the pipeline analog-to-digital converter, error extraction by means of adaptive iteration, stage-by-stage, sequentially from a last stage to a first stage of a pipeline. During quantization of error value, the invention performs, by means of a fitting-based adaptive algorithm, foreground extraction of a capacitance mismatch error, a gain bandwidth error, and a kickback error in each stage of the pipeline, without any additional circuit.
ANALOG-TO-DIGITAL CONVERTER CIRCUIT
There is provided an analog-to-digital converter circuit including: a first converter circuit generating a first digital code by performing analog-to-digital conversion on the basis of an input voltage; a second converter circuit generating a second digital code by performing, on the basis of the input voltage and the first digital code, analog-to-digital conversion over a voltage range wider than that. of a least significant. bit of the first converter circuit; an error detector detecting a conversion error of the analog-to-digital conversion on the basis of the first and second digital codes, thereby generating error data indicating a bit having a conversion error and the kind of the conversion error; and a calibration circuit estimating an error factor on the basis of the first and second digital codes and the error data, and performing calibration of a circuit relevant to the estimated error factor on the basis of an estimation result.
RESISTOR DAC GAIN CORRECTION
Systems and techniques for Digital-to-Analog Converter (DAC) gain correction are described herein. A digital-to-analog converter (DAC) circuit can include a switch bridge circuit having a first leg and a second leg that define respective mutually exclusive first and second DAC signal paths. The DAC circuit can further include a first compensation circuit configured to provide a first compensation current to the first leg of the switch bridge to compensate for a current defect caused by a voltage drop across a portion of the first DAC signal path. The DAC circuit can also include a second compensation circuit configured to provide a. second compensation current to a second leg of the switch bridge to compensate for a voltage drop across a portion of the second DAC signal path. The DAC circuit can be included in a larger circuit such as a continuous time sigma delta (CTSD) analog-to-digital converter (ADC).
ANALOG-TO-DIGITAL CONVERTER
An analog-to-digital converter according to one or more embodiments is disclosed that converts an analog input to a digital converted value by repeating a conversion data generation operation by a conversion data generator, a potential generation operation by a capacitance DAC, and a comparison operation by a comparator for a resolution bit, the analog-to-digital converter. a comparator operation signal generation circuit predicts the time when a potential generated by the capacitance DAC becomes settled based on a charging or discharging time to a capacitance element whose characteristics are equal to those of the capacitance used in the capacitance DAC, and generates a comparator operation signal to allow the comparator to start the comparison operation.
Cascode Class-A Differential Reference Buffer Using Source Followers for a Multi-Channel Interleaved Analog-to-Digital Converter (ADC)
A reference buffer has many legs each with an upper transistor, a lower transistor, and a resistor or current source as a tail device in series. The source or emitter of the upper (lower) transistor generates an upper (lower) reference voltage. This source follower transistor configuration has a low output impedance and high current. The gate or base of the upper (lower) transistors are driven by a first (second) control node. A control leg has an upper transistor, a lower transistor, and a tail device in series. The source and gate, or emitter and base, are connected together for the upper and lower transistors and generate the upper and lower control nodes. Alternately, the gate or base of the upper (lower) transistor is driven by an op amp receiving an upper (lower) bandgap voltage and the upper (lower) control node as negative feedback.
SIGMA DELTA ANALOG-TO-DIGITAL CONVERTER AND METHOD FOR ELIMINATING IDLE TONES OF SIGMA DELTA ANALOG-TO-DIGITAL CONVERTER
A Sigma Delta analog-to-digital converter (ADC) and a method for eliminating idle tones of the Sigma Delta ADC are provided. The Sigma Delta ADC includes a loop filter, a quantizer, an adder and a digital-to-analog converter (DAC). The loop filter performs filtering on a difference between an analog input signal and an analog feedback signal to generate a filtered signal. The quantizer is coupled to the loop filter, and generates a digital output signal according to the filtered signal. The adder is coupled to the quantizer, and adds a digital dithering signal to the digital output signal to generate a digital feedback signal. The DAC is coupled to the loop filter, and generates the analog feedback signal according to the digital feedback signal.