Intel Corporation

Intel Coproration

Yongping Fan

Ian A Young

Kuan-Yueh Shen

Gennady Goltman

Jeffrey E Smith

David E Duarte

Jing Li

You Li

Dan Zhang

Fangxing Wei

Jeffrey William Waldrip

Prantik K Nag

Hyung Seok Kim

Hong H Chan

Dongseok Shin

Bo Xiang

A low power hybrid reverse (LPHR) bandgap reference (BGR) and digital temperature sensor (DTS) or a digital thermometer, which utilizes subthreshold metal oxide semiconductor (MOS) transistors.

Low power hybrid reverse bandgap reference and digital temperature sensor

A low power hybrid reverse (LPHR) bandgap reference (BGR) and digital temperature sensor (DTS) or a digital thermometer, which utilizes subthreshold metal oxide semiconductor (MOS) transistor and the PNP parasitic Bi-polar Junction Transistor (BJT) device to form a reverse BGR that serves as the base for configurable BGR or DTS operating modes. The LPHR architecture uses low-cost MOS transistors and the standard parasitic PNP device. Based on a reverse bandgap voltage, the LPHR can work as a configurable BGR. By comparing the configurable BGR with the scaled base-emitter voltage, the circuit can also perform as a DTS with a linear transfer function with single-temperature trim for high accuracy.

A frequency doubler (tripler, or quadrupler) employs current re-use coupled oscillator technique to enhance phase noise without increasing current consumption. Frequency doubler uses coupling between two oscillators running at different frequencies; a first oscillator is running at the target frequency and a second oscillator is running at half the frequency. The coupling between the two oscillators is via a transformer having a primary transformer coil and a secondary transformer coil. The first oscillator comprises a differential inductor, coarse/fine tuning capacitor arrays, and an n-type trans-conductor (GM). A virtual ground node of the n-type GM is coupled to one side of the primary transformer coil and the other side of the primary coil is coupled to the center tap of the secondary coil. The second oscillator comprises the secondary coil, coarse/fine tuning capacitor arrays, n-type GM, frequency tracking loop (FTL) and 2-harmonic LC filter network.

Coupled frequency doubler with frequency tracking loop

Described is a low power and low jitter phase locked loop (PLL) or delay locked loop (DLL) with digital leakage compensation. The compensation is provided by an apparatus which comprises: a circuitry to generate a pulse with a digitally controlled pulse width, wherein the pulse width is proportional to a static phase error of a PLL or a DLL; and a charge pump coupled to the circuitry, wherein the charge pump is to receive the pulse and to source or sink current to or from a node according to the pulse width.

Low power and low jitter phase locked loop with digital leakage compensation

An apparatus is provided which comprises: an oscillator to generate a first clock having a first frequency; a divider coupled to the oscillator, wherein the divider is to generate a second clock having a second frequency; and a current reference generator comprising a switched capacitor circuitry which is to receive the second clock directly or indirectly.

Apparatus and method for generating stable reference current

Described is a phase-locked loop with lower power charge pump. The phase-locked loop comprises: a phase frequency detector to compare a reference clock and a feedback clock and generate a pulse based on the comparison, a charge pump to provide a charge signal corresponding to the pulse, a bias generator to provide biasing for the charge pump, wherein the bias generator is operable to receive a bias enable signal from the phase frequency detector and the bias generator is disabled when the bias enable signal is not asserted, a loop filter coupled to the output of the charge pump to provide a control signal responsive to the charge signal, and a voltage-controlled oscillator (VCO), wherein the oscillating frequency of the VCO is controlled by the control signal.

Phase-locked loop with lower power charge pump

Described is an apparatus to lower power of a charge pump. The apparatus comprises: a first delay unit to receive a reference clock, the first delay unit to provide a delayed reference clock to a first sequential unit; a second delay unit to receive a feedback clock, the second delay unit to provide a delayed feedback clock to a second sequential unit; a first logic unit to receive the reference and feedback clocks, the logic unit to perform a logical OR operation on the received reference and feedback clocks, and to generate a trigger signal for a third sequential unit; and a second logic unit to receive outputs of first and second sequential units, and to generate an output coupled to the third sequential unit.

Apparatus to reduce power of a charge pump

In some embodiments, provided are AFC circuits and methods for calibrating a second setting of an oscillator while a first setting is controlled by a temperature compensated control.

Temperature compensated PLL calibration

In some embodiments, disclosed is an AC amplitude detector to compare the magnitude of an AC signal against a detector threshold level and to provide an indication as to whether the AC magnitude is larger or smaller than the detector threshold level.

Clock amplitude detection

A temperature compensation apparatus may include a sense circuit configured to produce a sense voltage that is dependent on temperature and a temperature compensation circuit configured to receive the sense voltage and produce a temperature compensation control signal to control a compensation capacitor array of an oscillator. The temperature compensation circuit may be configured to calibrate the control signal to have a first value at a first temperature. The temperature compensation circuit may also be configured to calibrate a trimming level (e.g., slope) of the control signal.

Temperature compensation for oscillator

A loop filter is described. The loop filter has first and second inputs and an output. A loop filter capacitor is coupled to the loop filter output. Sample switches are coupled to the second loop filter input. A voltage divider is coupled to reset switches. Switched capacitors are coupled to sample switches, the reset switches, the loop filter capacitor, and the loop filter output.

Digitally switched capacitor loop filter

A mixed signal circuit architecture is disclosed for automatic frequency control and digital temperature compensation in an LC-PLL system. Some embodiments allow for high-volume manufacturing of products such as microprocessors and chipsets, and other circuits that employ LC-PLL technology. In some embodiments, various capacitor loadings can be selected to compensate for variation associated with process, voltage, temperature, and reference frequency. In addition, a multi-leg capacitor bank can be selectively used to further compensate for temperature variation post-lock, in accordance with some embodiments. A programmable timer can be used in some embodiments to allow for loop settling prior to assessing parameters of interest.

Automatic frequency control architecture with digital temperature compensation

A phase interpolator includes a first circuit to generate a first signal having a first phase delay and a second signal having a second phase delay and a phase mixer. The phase mixer is coupled to receive the first and second signals from the first circuit. The phase mixer includes multiple current drivers each including a current driver input coupled to selectively delay one of the first or second signals and a current driver output coupled to output a phase delayed signal. The current driver outputs of the current drivers are coupled together to combine the phase delayed signals from the current drivers to generate an output phase delayed signal having a phase interpolated from the first and second signals.

Phase interpolator

Disclosed are circuits and methods to control the amplitude of a signal generated by a VCO.

VCO amplitude control

A phase locked loop with a voltage controlled oscillator, where the voltage controlled oscillator includes a feedback loop and delay cells connected in a ring. Each delay cell has a biased pMOSFET to provide pull-up current and a biased nMOSFET to provide pull-down current. For each delay cell, the gate of the biased nMOSFET is biased by the control voltage provided by the phase locked loop, and the gate of the biased pMOSFET is biased at a bias voltage provided by the feedback loop. The biasing of the pMOSFETs is adjusted so that the pull-up and pull-down currents for each delay cell are matched, thereby providing a 50% duty cycle and good jitter performance over process, supply voltage variations, and temperature variations. Because only the feedback loop has non-zero static current, low power is expected. Other embodiments are described and claimed.

Growing community of inventors

Portland, OR, United States of America

Yongping Fan