Abstract: Systems and methods for process variation power control in three-dimensional integrated circuits (3DICs) are disclosed. In an exemplary aspect, at least one process variation sensor is placed in each tier of a 3DIC. The process variation sensors report information related to a speed characteristic for elements within the respective tier to a decision logic. The decision logic is programmed to weight output from the process variation sensors according to relative importance of logic path segments in the respective tiers. The weighted outputs are combined to generate a power control signal that is sent to a power management unit (PMU). By weighting the importance of the logic path segments, a compromise voltage may be generated by the PMU which is “good enough” for all the elements in the various tiers to provide acceptable performance.

Abstract: Methods and apparatus for identifying a process corner are provided. Provided is an exemplary method for identifying a process corner of an integrated circuit (IC). The IC has a first asymmetrical ring oscillator (ARO1) including pull-up transistors that have a low threshold voltage (LVT) and pull-down transistors that have a regular threshold voltage (RVT), and has a second asymmetrical ring oscillator (ARO2) including pull-up transistors that have an RVT and pull-down transistors having an LVT. The exemplary method includes applying an ultra-low power supply voltage to the ARO1 and the ARO2 that causes the integrated circuit to operate near a verge of malfunction, measuring an output frequency of the ARO1, measuring an output frequency of the ARO2, calculating a calculated ratio of the output frequency of the ARO1 and the output frequency of the ARO2, and comparing the calculated ratio to a fiduciary ratio to identify the process corner.

Abstract: A switchable supply network for powering multiple digital islands. In one embodiment, a first digital island includes a first power collapsible circuit and a first retention circuit, and a second digital island includes a second power collapsible circuit and a second retention circuit. In a normal mode of operation, the first digital island is provided a first supply voltage and a second digital island is provided a second supply voltage higher than the first supply voltage. In a transition mode the second power collapsible circuit is powered down and the second supply voltage is lowered and provided to the second retention circuit. When the second supply voltage falls below the first supply voltage, the first power collapsible circuit is powered down. The second supply voltage is now provided only to the retention circuits, and is furthered lowered in a retention mode to a final retention voltage.

Abstract: A voltage level shifter to provide an output logic signal in response to an input logic signal, where the input logic signal is in a first voltage domain and the output logic signal is in a second voltage domain. In one embodiment, a voltage boost module provides a boosted voltage in response to the input logic signal going HIGH, where the boosted voltage is sufficient to turn OFF a pull-up transistor operating in the second voltage domain. Contention among pull-down and pull-up transistors may be avoided.

Abstract: Clock distribution schemes with wide operating voltage ranges are disclosed. In one aspect, an operating voltage level or condition within a computing device is sensed. In a first voltage condition, delay elements are used within a clock tree to minimize clock skew. In a second voltage condition, one or more delay and/or clocked elements are bypassed to minimize clock skew at the second voltage condition. In addition to controlling clock skew, power may be conserved by depowering the bypassed elements. Controlling clock skew in this fashion improves operation of a computing device that includes the clock tree and may improve battery life.

Abstract: Clock tree design methods for ultra-wide voltage range circuits are disclosed. In one aspect, place and route software creates an integrated circuit (IC) in an optimal configuration at a first voltage condition. A first clock tree is created as part of the place and route process. Clock skew for the first clock tree is evaluated and minimized through insertion of bypassable delay elements. The delay elements are then removed from the wiring routing diagram. A second voltage condition is identified, and clock tree generation software is allowed to optimize the wiring routing diagram for the second voltage condition. The second clock tree generation software may insert more bypassable delay elements into the wiring routing diagram that allow clock skew optimization at the second voltage condition. The initial bypassable delay elements are then reinserted into the wiring routing diagram and a finished IC is established.

Abstract: The present disclosure relates to inhibiting address transitions in unselected memory banks of solid state memory circuits. Bank selection and address gating circuitry may be used to provide a set of gated address signals to decode circuitry for each memory bank, such that the gated address signals associated with unselected memory banks are prevented from transitioning and the gated address signals associated with a selected memory bank are based on clocking in the status of address signals provided by memory control circuitry.

Abstract: The present invention provides a PLA architecture where the AND plane is implemented with NAND logic. The OR plane may be implemented with various logic, but in one embodiment, the OR plane is implemented with NOR logic. The AND plane may have multiple sequential stages providing hierarchical NAND logic. The NAND logic may be broken into a hierarchy of NAND logic blocks. Each NAND logic block may include one or more series-connected NAND transistor stacks. Each transistor in the transistor stack may receive an input signal representing the product of a PLA clock signal and either a direct PLA input or the complement thereof. As such, the PLA clock is inherently integrated with the input signals that drive the various transistors of the NAND transistor stacks.