摘要:
In an integrated circuit, a layer including a plurality of conductive wires is described. A first wire, having sidewalls, is tapered from a proximal end which has a first width to a distal end which has a second width, to reduce width from the first width to the second width, and the first wire also has a substantially vertical surface. A second wire, spaced apart from the first wire, also has a substantially vertical surface. The first wire and the second wire are each horizontally disposed along side each other forming a part of a sidewall capacitor between facing sidewalls. Capacitors are created between the first substantially vertical surface and the second substantially vertical surface, the capacitors are respectively associated with capacitances and with a plurality of loads, the plurality of loads is progressively reduced responsive to a progressive reduction of the capacitances as associated with the first wire taper.
摘要:
A clock signal is monitored to detect a transition from a first logic state to a second logic state. Once this transition is detected, subsequent transitions of the clock signal are ignored for a predetermined time period during which signal interference is most significant. After lapse of the predetermined time period, the clock signal is again monitored to detect subsequent state transitions. In some embodiments, the clock signal is delayed using a delay circuit to produce a delayed clock signal which is used to force the clock signal to the second logic state for a predetermined time period. In one embodiment, the predetermined time period is user-selectable via one or more selectable taps on the delay circuit.
摘要:
A first wire having sidewalls of an integrated circuit is tapered from the proximal end to the distal end to reduce width from the first width to the second width. A second wire, spaced apart from the first wire, the second wire has sidewalls. The first wire and the second wire are each horizontally disposed along side each other forming a part of a sidewall capacitor between facing sidewalls. The sidewall capacitor capacitance is progressively reduced responsive to the first wire taper.
摘要:
An integrated circuit fabricated in a multiple oxide process can be used to provide a temperature-insensitive circuit. The temperature-insensitive circuit can be a ring oscillator; this ring oscillator can be used as a low-cost integrated reference frequency to monitor and to modify the behavior of the integrated to produce the desired results. In some embodiments, the reference oscillator output can be compared to second oscillator output where the second oscillator performance is temperature-sensitive. The comparison result can be monitored and processed to power down the integrated circuit.
摘要:
A method of and apparatus for generating a spread spectrum clock signal on an integrated circuit are provided. A target frequency generated by a ring oscillator can be modulated by varying a supply voltage to the ring oscillator, thereby changing the target frequency. In one embodiment, the supply voltage is generated by an analog multiplexer that can be digitally controlled. A fixed voltage source can provide an input signal to the analog multiplexer. In one embodiment, the fixed voltage source can be implemented with a unity gain amplifier.
摘要:
A method of implementing a design on a programmable logic device (PLD) includes generating a database that identifies correspondence between resources and programming frames of the PLD. A first PLD design is compiled, wherein the first design uses a first set of resources in a first manner. Costs associated with using the first set of resources of the first design in the first manner are reduced. A second PLD design is then compiled, applying the reduced costs associated with using the first set of resources. A second set of resources required to compile the second design is identified, wherein the second set of resources is not used in the same manner as the first set of resources. A set of programming frames associated with the second set of resources is identified. Costs associated with using a third set of resources associated with the set of programming frames are increased.
摘要:
Method and apparatus are described for duty cycle determination and adjustment. More particularly, an output signal is sampled and provided to duty cycle check circuitry which characterizes the duty cycle of the sampled output signal. This characterization may be provided to a wafer prober or integrated circuit tester to determine whether duty cycle is within an acceptance range. Alternatively, the duty cycle indicator signal may be provided to drive adjustment circuitry. In response to duty cycle not being within an acceptance range, drive adjust circuitry provides a drive adjustment signal to adjust duty cycle at an output buffer by turning on one or more p-channel drive transistors, one or more n-channel drive transistors, or a combination of both. Moreover, wells may be biased responsive to a detected duty cycle in order to correct the duty cycle.
摘要:
A die having a bypass capacitor is stacked on another die having an active circuit. The active circuit draws a spike of current, for example, during a switching period of a voltage on its output lead from one digital logic level to another digital logic level. The bypass capacitor provides a portion of the spike of current through a conductive plug that extends from a plate of the bypass capacitor to a power lead of the active circuit. The length of the conductive plug is reduced by extending the conductive plug from the bypass capacitor to the active circuit orthogonally to the planar orientation of the dice. Reducing the length of the conductive plug reduces the resistance and inductance of the conductive plug and, in turn, reduces the drop in voltage between the voltage on the bypass capacitor and the voltage on the power lead of the active circuit.
摘要:
Method and apparatus are described for providing memory cells enhanced for resistance to single event upsets. In one embodiment, transistors are coupled between cross coupled inverters of a latch, thus in a small area providing both single-event-upset resistivity most of the time, and high speed during writing to the memory cell. Alternatively, inductors coupled between inverters of a latch may be used.
摘要:
The supply voltage to which a delay circuit's buffer stages are coupled is adjusted in response to changes in temperature according to a predetermined relationship to maintain a substantially constant buffer stage gate delay over temperature variations. Decreasing gate delays resulting from decreases in temperature are offset by decreasing the supply voltage, which in turn increases gate delays. Conversely, increasing gate delays resulting from increases in temperature are offset by increasing the supply voltage, which in turn decreases gate delays. In some embodiments, a control circuit is connected to the reference voltage circuit that supplies VCC to the delay circuit, and adjusts VCC in response to temperature to maintain substantially constant gate delay over temperature. In one embodiment, the control circuit includes a microprocessor and a look-up table containing desired supply voltage versus temperature mappings. In another embodiment, the control circuit is formed as part of an existing bandgap reference circuit associated with the reference voltage circuit, and therefore consumes minimal silicon area.