The present invention relates to a digital-analog conversion method and device for adjusting a reference current to be used in a digital-analog conversion, by using a common mode feedback device, and the digital-analog conversion method of the present invention comprises the steps of: generating a reference current by receiving a reference voltage; converting a digital signal into an analog signal by receiving the generated reference current; detecting a common mode voltage, which is the average value of a both-end voltage of the converted analog signal; comparing the detected common mode voltage with the reference voltage; generating a feedback signal on the basis of the comparison result; and adjusting the reference current according to the generated feedback signal.

A DAC design uses a passive reconstruction filter. The reconstruction filter includes a notch filter and series peaking filter (low pass filter with peaking in the signal passband). The notch filter provides notch filtering at the DAC clock frequency. The peaking filter increases signal bandwidth while attenuating frequency contents at harmonics of the DAC clock frequency. The notch filter can be an LC notch filter with at least one notch inductor Ln and at least one notch capacitor Cn. The peaking filter can be a series peaking inductor Ls (shunted with a filter capacitor Cp). In a differential configuration, the passive reconstruction filter can be configured with LC notch filters (with Ln notch inductors), and the peaking filter can be Ls peaking inductors coupled in series to the LC notch filters. The Ln notch inductors, Ls peaking inductors can be mutually wound as single inductors. For an example direct conversion RF transmit chain, IQ signal paths are implemented with differential DAC designs including passive reconstruction filters.

A single-ended receiver includes an internal voltage generation circuit to set a first internal reference voltage (Vref). A model voltage generation circuit is configurable to receive an external reference voltage to be calibrated during an initial calibration. The model voltage generation circuit is configurable to track an offset value for voltage-temperature (VT) drift and the offset value is applied to the internal voltage generation circuit to calibrate the internal Vref during a periodic calibration of the single-ended receiver.

A single-ended receiver includes an internal voltage generation circuit to set a first internal reference voltage (Vref). A model voltage generation circuit is configurable to receive an external reference voltage to be calibrated during an initial calibration. The model voltage generation circuit is configurable to track an offset value for voltage-temperature (VT) drift and the offset value is applied to the internal voltage generation circuit to calibrate the internal Vref during a periodic calibration of the single-ended receiver.

A digital to analog conversion circuit, DAC, comprises a number of serializing lanes, each serializing lane comprising at least two bit inputs, and each serializing lane being configured to output the two bit inputs serially via a serialized output port at a predetermined first clock rate. The DAC further comprises a number of non-serializing lanes, each non-serializing lane comprising at least two bit inputs and each non-serializing lane being configured to output the two bit inputs in parallel each via a separate parallel output port, at a second clock rate, which is half the clock rate of the first clock rate, and a current switching network comprising a bit input port for every one of the serialized output ports and for every one of the parallel output ports and being configured to produce a output current, based on the signals received via the bit input ports.

Methods, apparatus and articles of manufacture (e.g., physical storage media) to calibrate interpolating string digital-to-analog converters are disclosed. Example methods disclosed herein to calibrate a digital-to-analog converter (DAC) include determining a first calibration codeword based on a first nonlinearity error value measured at an output of the DAC when a most-significant-bit (MSB) portion of an input codeword is applied to an input of the DAC. Such disclosed example methods also include determining a second calibration codeword based on a second measured nonlinearity error value measured at the output of the DAC when a least-significant-bit (LSB) portion of the input codeword is applied to the input of the DAC. Such disclosed example methods further include combining the first calibration codeword and the second calibration codeword to determine a third calibration codeword to be accessed by the DAC to calibrate the output of the DAC when the input codeword is applied to the DAC.

A layout method for a current source array. A digital-to-analog converter (DAC) includes a plurality of complementary metal-oxide-semiconductor (CMOS) devices. Current sources for the CMOS devices are uniformly arranged in a one-dimensional array. The spacing between the current sources in the one-dimensional array is determined using a golden ratio.

A layout method for a current source array. A digital-to-analog converter (DAC) includes a plurality of complementary metal-oxide-semiconductor (CMOS) devices. Current sources for the CMOS devices are uniformly arranged in a one-dimensional array. The spacing between the current sources in the one-dimensional array is determined using a golden ratio.

Systems and methods according to one or more embodiments are provided for a high speed digital to analog upconverter that provides for converting a plurality of parallel digital data bits to an analog output signal. In one example, a system includes a decoder circuit configured to receive a plurality of decoder input data bits and provide a plurality of decoded parallel digital data bits. The system also includes a mixer circuit configured to combine each of the decoded parallel digital data bits with a conversion clock signal to provide frequency shifted digital data bits, wherein the frequency shifted digital data bits are time misaligned with each other. The system also includes a synchronizer circuit configured to time align the frequency shifted digital data bits. The system further includes a switching network configured to generate an analog output signal in response to the time aligned frequency shifted digital data bits.

Systems and methods according to one or more embodiments are provided for a high speed digital to analog upconverter that provides for converting a plurality of parallel digital data bits to an analog output signal. In one example, a system includes a decoder circuit configured to receive a plurality of decoder input data bits and provide a plurality of decoded parallel digital data bits. The system also includes a mixer circuit configured to combine each of the decoded parallel digital data bits with a conversion clock signal to provide frequency shifted digital data bits, wherein the frequency shifted digital data bits are time misaligned with each other. The system also includes a synchronizer circuit configured to time align the frequency shifted digital data bits. The system further includes a switching network configured to generate an analog output signal in response to the time aligned frequency shifted digital data bits.