Abstract: A chip includes a first modulator configured to receive a first internal signal, and convert the first internal signal into a first output signal including a first pattern, and a second modulator configured to receive a second internal signal, and convert the second internal signal into a second output signal including a second pattern distinct from the first pattern. The chip also includes an observation pad, and a merge circuit coupled to the observation pad, wherein the merge circuit is configured to merge the first output signal and the second output signal into a merged output signal, and output the merged output signal to the observation pad, wherein the merged output signal includes the first pattern and the second pattern, and the first pattern and the second pattern are spaced apart in the merged output signal.

Abstract: In certain aspects, a system includes a first clock source configured to generate a first clock signal, a second clock source configured to generate a second clock signal, a clock path, and an OR gate having a first input, a second input, and an output, wherein the output of the OR gate is coupled to the clock path. The system also includes a first clock gating circuit coupled between the first clock source and the first input of the OR gate, and a second clock gating circuit coupled between the second clock source and the second input of the OR gate.

Abstract: A memory interface circuit includes a first receiver coupled to a differential data strobe signal and a second receiver that has a first input coupled to a reference voltage source and a second input coupled to one of the pair of complementary signals. A qualification circuit is configured to detect a preamble transmission in the differential data strobe signal based on timing provided by an output of the first receiver when the memory interface circuit is in a first operating state, detect the preamble transmission in the differential data strobe signal based on timing provided by an output of the second receiver when the memory interface circuit is in a second operating state, and assert a preamble detection signal when the preamble transmission is detected. A gating circuit is configured to provide a receive clock signal when the preamble detection signal is asserted.

Abstract: A memory interface circuit includes a first receiver coupled to a differential data strobe signal and a second receiver that has a first input coupled to a reference voltage source and a second input coupled to one of the pair of complementary signals. A qualification circuit is configured to detect a preamble transmission in the differential data strobe signal based on timing provided by an output of the first receiver when the memory interface circuit is in a first operating state, detect the preamble transmission in the differential data strobe signal based on timing provided by an output of the second receiver when the memory interface circuit is in a second operating state, and assert a preamble detection signal when the preamble transmission is detected. A gating circuit is configured to provide a receive clock signal when the preamble detection signal is asserted.

Abstract: In some aspects, an electronic device may detect a start of a voltage ramp transition period associated with changing a voltage at which an integrated circuit operates from a first voltage to a second voltage, wherein changing the voltage from the first voltage to the second voltage causes changes to one or more parameters that impact performance associated with the integrated circuit during the voltage ramp transition period. The electronic device may trigger, responsive to detecting the start of the voltage ramp transition period, a dynamic calibration mode that compensates for the changes to the one or more parameters that impact the performance associated with the integrated circuit during the voltage ramp transition period. The electronic device may exit the dynamic calibration mode responsive to detecting an end of the voltage ramp transition period. Numerous other aspects are described.

Abstract: A memory interface circuit has a first differential receiver having a first input coupled to a first reference voltage source, a second differential receiver configured to receive a differential data strobe signal in a pair of complementary signals, a third differential receiver having a first input coupled to a second reference voltage source and a second input configured to receive one of the pair of complementary signals, a clock generation circuit configured to generate a read clock signal based on an output of the second differential receiver and using a qualifying signal output by the third differential receiver to qualify one or more edges in the read clock signal and a data capture circuit clocked by the read clock signal and configured to capture data from the output of the first differential receiver using the one or more edges in the read clock signal.

Abstract: In certain aspects, a system includes a first clock source configured to generate a first clock signal, a second clock source configured to generate a second clock signal, a clock path, and an OR gate having a first input, a second input, and an output, wherein the output of the OR gate is coupled to the clock path. The system also includes a first clock gating circuit coupled between the first clock source and the first input of the OR gate, and a second clock gating circuit coupled between the second clock source and the second input of the OR gate.

Abstract: A memory interface circuit has a first differential receiver having a first input coupled to a first reference voltage source, a second differential receiver configured to receive a differential data strobe signal in a pair of complementary signals, a third differential receiver having a first input coupled to a second reference voltage source and a second input configured to receive one of the pair of complementary signals, a clock generation circuit configured to generate a read clock signal based on an output of the second differential receiver and using a qualifying signal output by the third differential receiver to qualify one or more edges in the read clock signal and a data capture circuit clocked by the read clock signal and configured to capture data from the output of the first differential receiver using the one or more edges in the read clock signal.

Abstract: A method for clock switching includes propagating a first clock signal through a first clock path, propagating a second clock signal through a second clock path, generating a first delay control signal based on the first clock signal, and generating a second delay control signal based on the second clock signal. The method also includes, in a first mode, coupling the first clock path to a delay circuit and inputting the first delay control signal to a control input of the delay circuit. The method also includes, in a second mode, coupling the second clock path to the delay circuit and inputting the second delay control signal to the control input of the delay circuit.