Test circuit to isolate HCI degradation

A system for synchronizing switching events, the system comprising:

• a controller;
• a clock generator communicatively coupled to the controller;
• and
• a delay chain communicatively coupled to the controller;
• wherein the delay chain is configured to perform a plurality of first delay chain switching events in response to an input to the delay chain;
• wherein the controller is configured to initiate a synchronization phase comprising:
• enabling the clock generator to provide as an input to the delay chain a clock generator output at a synchronization frequency and a synchronization duty cycle, wherein the clock generator output passing through the delay chain synchronizes the plurality of delay chain switching events to occur at the synchronization frequency and the synchronization duty cycle resulting in an output frequency of the delay chain and an output duty cycle of the delay chain being synchronized to the synchronization frequency and the synchronization duty cycle of the clock generator output;
• and
• a synchronization/stress phase comprising further enabling the clock generator to provide to the delay chain the clock generator output for a duration that is sufficient to stress the delay chain;
• wherein the controller is further configured to initiate a reconfigure phase comprising reconfiguring the delay chain to operate as a ring oscillator.

A system for synchronizing switching events, the system comprising:

• a controller;
• a clock generator communicatively coupled to the controller;
• and
• a delay chain communicatively coupled to the controller;
• wherein the delay chain is configured to perform a plurality of delay chain switching events in response to an input to the delay chain;
• wherein the controller is configured to initiate a synchronization/stress phase comprising:
• enabling the clock generator to provide as an input to the delay chain a clock generator output at a synchronization frequency and a synchronization duty cycle, wherein the clock generator output passing through the delay chain synchronizes the plurality of delay chain switching events to occur at the synchronization frequency and the synchronization duty cycle resulting in an output frequency of the delay chain and an output duty cycle of the delay chain being synchronized to the synchronization frequency of the clock generator output and the synchronization duty cycle of the clock generator output, wherein the clock generator output is provided to the delay chain for a duration that is sufficient to stress the delay chain;
• wherein the controller is further configured to initiate a reconfigure phase comprising:
• reconfiguring the delay chain to operate as a ring oscillator;
• wherein, prior to the synchronization phase, a frequency of the plurality of delay chain switching events is less than the synchronization frequency.

A method for synchronizing switching events, the method comprising:

• initiating, using a controller, a synchronization phase comprising:
• enabling a clock generator to provide as an input to a delay chain a clock generator output at a synchronization frequency, wherein the clock generator output passing through the delay chain synchronizes a plurality of first delay chain switching events to occur at the synchronization frequency resulting in a frequency of an output of the delay chain being synchronized to the synchronization frequency of the clock generator output;
• and
• initiating, using the controller, a reconfigure phase comprising reconfiguring the delay chain to operate as a ring oscillator;
• wherein reconfiguring the delay chain to operate as the ring oscillator comprises coupling the output of the delay chain to an input of the delay chain;
• wherein the ring oscillator is configured to perform a plurality of ring oscillator switching events at a ring oscillator frequency that is independent of the synchronization frequency.