Performance-screen ring oscillator with switchable features
AssigneeInternational Business Machines Corporation
InventorsJohn B. DeForge, Kirk D. Peterson, Theresa Newton, Andrew Turner, Terence B. Hook
Life of this patent
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Abstract
A method and performance-screen ring oscillator (PSRO) test structure for designing, testing, and manufacturing a VLSI device. The performance-screen ring oscillator (PSRO) test structure comprises a ring oscillator having a plurality of stages; one or more selectable loads, each selectable load being coupled to an output of a corresponding one of the stages of the ring oscillator; and one or more multiplexers, each multiplexer being coupled to at least one stage of the ring oscillator and being configured to select a configuration of the corresponding selectable load.
Claims15
A performance-screen ring oscillator (PSRO) test structure, the performance-screen ring oscillator (PSRO) test structure comprising:
- a ring oscillator having a plurality of stages;
- two or more selectable loads, each selectable load configured to be selectively coupled to an output of a corresponding stage of the ring oscillator;
- and
- one or more multiplexers, an output of each multiplexer being coupled to an output of at least one stage of the ring oscillator and at least two inputs of each multiplexer being coupled to a corresponding one of the selectable loads, the multiplexer being configured to connect one of the selectable loads to the output of the corresponding stage of the ring oscillator.
A performance-screen ring oscillator (PSRO) test structure, the performance-screen ring oscillator (PSRO) test structure comprising:
- a ring oscillator having a plurality of stages;
- one or more selectable loads, each selectable load being coupled to an output of a corresponding one of the stages of the ring oscillator;
- and
- one or more multiplexers, each multiplexer being coupled to an output of at least one stage of the ring oscillator and being configured to select a configuration of the corresponding selectable load, wherein the selectable load in a first mode is a 180 degree out-of-phase signal.
A performance-screen ring oscillator (PSRO) test structure, the performance-screen ring oscillator (PSRO) test structure comprising:
- a ring oscillator having a plurality of stages;
- one or more selectable loads, each selectable load being coupled to an output of a corresponding one of the stages of the ring oscillator;
- and
- one or more multiplexers, each multiplexer being coupled to an output of at least one stage of the ring oscillator and being configured to select a configuration of the corresponding selectable load, wherein the selectable load in a third mode is alternating current (AC) ground.
A performance-screen ring oscillator (PSRO) test structure, the performance-screen ring oscillator (PSRO) test structure comprising:
- a ring oscillator having a plurality of stages;
- one or more selectable loads, each selectable load being coupled to an output of a corresponding one of the stages of the ring oscillator;
- and
- one or more multiplexers, each multiplexer being coupled to an output of at least one stage of the ring oscillator and being configured to select a configuration of the corresponding selectable load, wherein the selectable load in a fourth mode is a signal having a variable phase.
A performance-screen ring oscillator (PSRO) test structure, the performance-screen ring oscillator (PSRO) test structure comprising:
- a ring oscillator having a plurality of stages;
- one or more selectable loads, each selectable load being coupled to an output of a corresponding one of the stages of the ring oscillator;
- and
- one or more multiplexers, each multiplexer being coupled to an output of at least one stage of the ring oscillator and being configured to select a configuration of the corresponding selectable load, wherein the selectable load in a fifth mode is an electrical float.
Dependencies are inferred from the claim text.