Abstract: A crystal oscillator achieves fast start-up by injecting an in-band periodic signal into the crystal oscillator driver circuit. The in-band periodic signal has a frequency that is within a bandwidth of the crystal oscillator. Injection of the in-band periodic signal begins in response to a power-up condition and stops after a predetermined time period corresponding to the amount of time it takes to ensure the crystal driver is achieving full swing.

Abstract: A phase locked loop (PLL) includes a first loop, a second loop, and a lock detector. The first loop locks a feedback signal having a frequency equal to a fraction of a frequency of an output signal to a reference signal in phase. The first loop has a first bandwidth. The second loop locks the feedback signal to the reference signal in frequency and has a second bandwidth. The first bandwidth is higher than the second bandwidth. The lock detector is coupled to the second loop and increases the second bandwidth in response to detecting that the feedback signal is not locked to the reference signal.

Abstract: A phase locked loop (PLL) includes a first loop, a second loop, and a lock detector. The first loop locks a feedback signal having a frequency equal to a fraction of a frequency of an output signal to a reference signal in phase. The first loop has a first bandwidth. The second loop locks the feedback signal to the reference signal in frequency and has a second bandwidth. The first bandwidth is higher than the second bandwidth. The lock detector is coupled to the second loop and increases the second bandwidth in response to detecting that the feedback signal is not locked to the reference signal.

Abstract: A device may generate a clock signal using spread-spectrum clocking. The spread-spectrum clocking may modulate a frequency of the clock signal to produce a plurality of frequencies for the clock signal during a modulation cycle. The device may receive an instruction to disable the spread-spectrum clocking, and may disable the spread spectrum clocking at the end of the modulation cycle.

Abstract: A method and a phase-locked loop (PLL) for generating output clock signals with desired frequencies are described. The PLL is equipped with a ramp generator that increments or decrements a feedback divider value before providing it to a modulator. The modulator modulates the feedback divider value and provides the modulated value to a feedback divider of the PLL for performing frequency division.

Abstract: A device may generate a clock signal using spread-spectrum clocking. The spread-spectrum clocking may modulate a frequency of the clock signal to produce a plurality of frequencies for the clock signal during a modulation cycle. The device may receive an instruction to disable the spread-spectrum clocking, and may disable the spread spectrum clocking at the end of the modulation cycle.

Abstract: The loop bandwidth of a PLL is adjusted based on a difference between the output signal of the PLL and the PLL reference signal. In an embodiment, the DC open loop gain and natural frequency of the PLL are adjusted based on the phase difference between the output signal and the reference signal, so that the loop bandwidth of the PLL is increased when the phase difference is outside a programmable range and is decreased when the phase difference is within the programmable range.

Abstract: A method and a phase-locked loop (PLL) for generating output clock signals with desired frequencies are described. The PLL is equipped with a ramp generator that increments or decrements a feedback divider value before providing it to a modulator. The modulator modulates the feedback divider value and provides the modulated value to a feedback divider of the PLL for performing frequency division.

Abstract: Wafer sort data can be converted to binary data, whereby each integrated circuit of the wafer is assigned a value of one or zero, depending on whether test data indicates the integrated circuit complies with a specification. In addition, each integrated circuit is assigned position data to indicate its position on the wafer. A frequency transform, such as a multidimensional discrete Fourier transform (DFT), is applied to the binary wafer sort data and position data to determine a spatial frequency spectrum that indicates error patterns for the wafer. The spatial frequency spectrum can be analyzed to determine the characteristics of the wafer formation process that resulted in the errors, and the wafer formation process can be modified to reduce or eliminate the errors.