A delay circuit includes precharge and discharge transistors configured to receive an input signal. The delay circuit also includes a resistor coupled to the precharge transistor having a negative temperature coefficient to thereby form a node. A capacitive device and an inverter are coupled to the node. The inverter produces an output signal. Responsive to the input signal having a first polarity, the precharge transistor is configured to be turned on and the discharge transistor is configured to be turned off to thereby cause current to flow through the precharge transistor to the capacitive device to thereby charge the capacitive device. Responsive to the input signal having a second polarity, the precharge and discharge transistors are configured to change state to thereby cause charge from the capacitive device to discharge through the resistor and through the discharge transistor. The voltage on the node decays to a level which eventually causes the inverter's output to change state.

A delay circuit includes precharge and discharge transistors configured to receive an input signal. The delay circuit also includes a resistor coupled to the precharge transistor having a negative temperature coefficient to thereby form a node. A capacitive device and an inverter are coupled to the node. The inverter produces an output signal. Responsive to the input signal having a first polarity, the precharge transistor is configured to be turned on and the discharge transistor is configured to be turned off to thereby cause current to flow through the precharge transistor to the capacitive device to thereby charge the capacitive device. Responsive to the input signal having a second polarity, the precharge and discharge transistors are configured to change state to thereby cause charge from the capacitive device to discharge through the resistor and through the discharge transistor. The voltage on the node decays to a level which eventually causes the inverter's output to change state.

An example frequency converter includes a drift canceling loop with a balanced delay and a linear signal path (e.g., linear with respect to frequency scaling, amplitude modulation, and/or phase modulation). One side of the drift canceling loop includes a fixed delay, and the opposite side includes an adjustable, complementary delay. The adjustable, complementary delay facilitates precision matching of the signal delays on each side of the loop over a range of frequencies, which results in a significant improvement in noise cancelation, particularly at large offsets to the carrier, while permitting the use of a higher noise, but very fast tuning course scale oscillator. The linear signal path from the signal generator to an RF output facilitates modulation of the signal by the signal generator. A modular format is an advantageous embodiment of the invention that includes the removal of the frequency synthesizer's low phase noise reference into a separate module.

An example frequency converter includes a drift canceling loop with a balanced delay and a linear signal path (e.g., linear with respect to frequency scaling, amplitude modulation, and/or phase modulation). One side of the drift canceling loop includes a fixed delay, and the opposite side includes an adjustable, complementary delay. The adjustable, complementary delay facilitates precision matching of the signal delays on each side of the loop over a range of frequencies, which results in a significant improvement in noise cancelation, particularly at large offsets to the carrier, while permitting the use of a higher noise, but very fast tuning course scale oscillator. The linear signal path from the signal generator to an RF output facilitates modulation of the signal by the signal generator. A modular format is an advantageous embodiment of the invention that includes the removal of the frequency synthesizer's low phase noise reference into a separate module.

A system and method for efficiently capturing data by sequential circuits across multiple operating conditions are described. In various implementations, an integrated circuit includes multiple signal arrival adjusters both at its I/O boundaries and across its die. The signal arrival adjuster includes two internal timing paths, each with a respective latency. The signal arrival adjuster receives an input signal, and generates an output signal from the a selected one of the first timing path and the second timing path. The signal arrival adjuster sends the output signal to a sequential circuit. The sequential circuit uses the output signal as one of an input data signal and an input clock signal. The selection between the two timing paths within the signal arrival adjuster aids satisfying the setup and hold time requirements of the sequential circuit.

A slicer circuit for use in a N-tap, S-bit symbol look-ahead decision feedback equalizer (DFE) wherein the slicer comprises overflow adders and sign adders, the slicer circuit including a first processing path for generating, based on a signal sample y(n), a most significant bit (MSB) for each of 2.sup.S*N possible output symbols of the DFE, the first processing path including (2.sup.S*N)/2 overflow adder circuits, and a second processing path for generating, based on the signal sample y(n), a least significant bit (LSB) for each of the 2.sup.S*N possible output symbols, the second processing path including 2.sup.S*N sign adder circuits.

The disclosure provides a phase locked loop, PLL, for phase locking an output signal to a reference signal. The PLL comprises a reference path providing the reference signal to a first input of a phase detector, a feedback loop providing the output signal of the PLL as a feedback signal to a second input of the phase detector, a controllable oscillator generating the output signal based on at least a phase difference between reference and feedback signal, a digital-to-time converter, DTC, delaying a signal that is provided at one of the first and second input, a delay calculation path for calculating a DTC delay value. The PLL further comprises a randomization unit for generating and adding a random offset, i.e. a pseudo-random integer, to the delay value. The offset is such that a target output of the phase detector remains substantially unchanged.

The disclosure provides a phase locked loop, PLL, for phase locking an output signal to a reference signal. The PLL comprises a reference path providing the reference signal to a first input of a phase detector, a feedback loop providing the output signal of the PLL as a feedback signal to a second input of the phase detector, a controllable oscillator generating the output signal based on at least a phase difference between reference and feedback signal, a digital-to-time converter, DTC, delaying a signal that is provided at one of the first and second input, a delay calculation path for calculating a DTC delay value. The PLL further comprises a randomization unit for generating and adding a random offset, i.e. a pseudo-random integer, to the delay value. The offset is such that a target output of the phase detector remains substantially unchanged.

A charge pump circuit includes a first charge pump unit and a second charge pump unit. The first charge pump unit pumps an input voltage to output a first pumped voltage according to a first clock signal, a second clock signal and a third clock signal. The second charge pump unit pumps the first pumped voltage to output a second pumped voltage according to the first clock signal, a fourth clock signal and the third clock signal. The first clock signal and the third clock signal are non-overlapping clock signals. A falling edge of the second clock signal leads a rising edge of the first clock signal. A falling edge of the fourth clock signal leads a rising edge of the third clock signal.

A biased impedance circuit, an impedance adjustment circuit, and an associated signal generator are provided. The biased impedance circuit is coupled to a summation node and applies a biased impedance to the summation node. A periodic input signal is received at the summation node. The biased impedance circuit includes a switching circuit for receiving an output window signal, wherein a period of the output window signal is shorter than a period of the periodic input signal. The switching circuit includes a low impedance path and a high impedance path. The low impedance sets the biased impedance to a first impedance when the output window signal is at a first voltage level. The high impedance path sets the biased impedance to a second impedance when the output window signal is at a second voltage level. The first impedance is less than the second impedance.