摘要:
Methods and apparatus for calibration and temperature compensation of oscillators having mechanical resonators are described. The method(s) may involve measuring the frequency of the oscillator at multiple discrete temperatures and adjusting compensation circuitry of the oscillator at the various temperatures. The compensation circuitry may include multiple programmable elements which may independently adjust the frequency behavior of the oscillator at a respective temperature. Thus, adjustment of the frequency behavior of the oscillator at one temperature may not alter the frequency behavior at a second temperature.
摘要:
A double sampled switched capacitor architecture as described herein includes an amplifier having two separate inputs corresponding to two separate amplifier sections. The amplifier uses a first differential transistor pair for the first amplifier section, a second differential transistor pair for the second amplifier section, a first tail current bias arrangement for the first differential transistor pair, and a second tail current bias arrangement for the second differential transistor pair. The tail current bias arrangements are driven by a bias switching architecture that alternately activates one tail current bias arrangement while at least partially deactivating the other tail current bias arrangement. The amplifier and bias switching architecture cooperate to eliminate gain error that would otherwise be caused by a common parasitic capacitance shared by a single amplifier section.
摘要:
A method for placing tiles in an integrated circuit has matched devices that includes the steps of (1) calculating a metal spacing for tiles to be placed adjacent to the matched device in the integrated circuit; (2) calculating a lateral spacing for tiles to be placed adjacent to the matched device in the integrated circuit; (3) placing tiles about the matched device based on the metal spacing and the lateral spacing; (4) performing a density test in an area around the matched device; and (5) if a density test is not satisfied in the area around the matched device, dividing the matched device into at least two subdevices and repeating, with respect to each subdevice, the steps of calculating a metal spacing, calculating a lateral spacing, and placing tiles about each subdevice. The method is further adaptable to various kinds of matched devices including poly resistors, diffused resistors, double-poly capacitors, metal-insulator-metal capacitors, and fringe capacitors.
摘要:
Methods and apparatus for calibration and temperature compensation of oscillators having mechanical resonators are described. The method(s) may involve measuring the frequency of the oscillator at multiple discrete temperatures and adjusting compensation circuitry of the oscillator at the various temperatures. The compensation circuitry may include multiple programmable elements which may independently adjust the frequency behavior of the oscillator at a respective temperature. Thus, adjustment of the frequency behavior of the oscillator at one temperature may not alter the frequency behavior at a second temperature.
摘要:
Methods and apparatus for tuning devices having resonators are described. Phase shifters are included in the circuits and used to shift the phase of the output signal(s) of the resonators. In some implementations, the phase shifters are configured in a feedback loop with the resonators. One or more of the apparatus described herein may be implemented as part, or all, of a microelectromechanical system (MEMS).
摘要:
Methods and apparatus for tuning devices having resonators are described. Phase shifters are included in the circuits and used to shift the phase of the output signal(s) of the resonators. In some implementations, the phase shifters are configured in a feedback loop with the resonators. One or more of the apparatus described herein may be implemented as part, or all, of a microelectromechanical system (MEMS).
摘要:
A switched-capacitor gain stage suitable for use with a pipelined analog to digital converter (“ADC”) is capable of processing two or more input channels. The analog input voltages from the multiple channels are concurrently sampled (every other clock phase), and the gain stage processes the samples using a double sampling technique, generates residual voltage samples (every clock phase), and generates digital outputs for the multiple channels in an alternating manner. The gain stage provides equal input loading for the input stages, which enhances the performance of the ADC.
摘要:
The present invention provides a method for tiling an integrated circuit having a critically matched device such as a transistor. The method obtains an advantage of automatically improving metallic density over critically matched devices thus yielding improved CMP. The method may include the steps of: identifying critically matched devices in the integrated circuit; placing metal tiles over the critically matched device; performing a density test around each critically matched device; and if a density test is not satisfied around a critically matched device, placing at least one metal strip over a critically matched device.
摘要:
A pixel signal amplification circuit (200) receives a signal from a pixel element. A first semiconductor switch (225a) is connected to the pixel element and transfers a reset value of the pixel signal to a first storage capacitor (C1). A second semiconductor switch (235a) is also connected to the pixel element and transfers a sampled pixel signal to a second storage capacitor (C3). A differential voltage amplifier (OP1) generates an amplified signal of the difference between the values stored on the first and second storage capacitors (C1 and C3).