Qualcomm Incorporated

Rambus Inc.

Farrukh Aquil

Frederick Abbott Ware

Amir Amirkhany

Dinesh D Patil

Kambiz Kaviani

Yong Xu

Vaishnav Srinivas

Boris Andreev

Michael Drop

Philip Michael Clovis

Mahalingam Nagarajan

Vikas Mahendiyan

Ravindra Arvind Khedkar

Patrick Isakanian

Vinod Chamarty

Edwin Jose

Satish Krishnamoorthy

Sean Sweeney

Trang Nguyen

Joon Young Park

Xin Kang

Vishal Mishra

In some aspects, an electronic device may receive a clock signal having a first frequency. The electronic device may receive, for a chip select training operation, a chip select signal having a pattern including high pulses and low pulses. The electronic device may perform, for a sampling window, the chip select training operation using the clock signal and the chip select signal, wherein the sampling window includes a quantity of pulses of the chip select signal. The electronic device may provide, via a first data in or out (DQ) pin, an indication of a first result of the chip select training operation for the high pulses of the chip select signal. The electronic device may provide, via a second DQ pin, an indication of a second result of the chip select training operation for the low pulses of the chip select signal. Numerous other aspects are described.

Enhanced chip select signal training

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.

Read data capture for a high-speed double data rate interface

Embodiments generally relate to a memory device. In one embodiment, the memory device includes a clock receiver circuit that receives an external clock signal and provides an internal clock signal. The memory device also includes a delay-locked loop circuit (DLL) having an input, and a circuit that receives the internal clock signal. The circuit selects which pulses of the internal clock signal are applied to the input of the DLL, such that no more than two clock pulses selected from at least three consecutive pulses of the external clock signal are applied to the input of the DLL during a predetermined interval. In another embodiment, a method includes receiving an external clock signal at a clock receiver circuit, receiving an internal clock signal from the clock receiver circuit, and selecting which pulses of the internal clock signal are applied to an input of a DLL, where no more than two clock pulses selected from at least three consecutive pulses of the external clock signal are applied to the input of the DLL during a predetermined interval.

Optimizing power in a memory device

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.

Clock qualifier enhancement for external double data rate memory interfaces

Methods and apparatuses for improve clocking scheme to reduce power consumption are presented. The apparatus includes a host configured to communicate with a memory via a link. The host is further configured to receive a first clock from the memory; to receive, based on the first clock, data from the memory, in a first mode of a read operation; to generate a second clock, the second clock being generated independent of the first clock; and to receive, based on the second clock, data from the memory, in a second mode of the read operation.

Clocking scheme to receive data

Signal timing drift in a synchronous dynamic random access memory (SDRAM) system may be compensated for by performing write signal timing training using a multi-purpose command (MPC) first-in-first-out (FIFO) write and MPC FIFO read at periodic intervals interspersed with mission-mode SDRAM traffic. The test result samples obtained from the write signal timing training may be analyzed independently of mission-mode SDRAM traffic. The mission-mode timing of the SDRAM data bit signals relative to the SDRAM write clock signal may be adjusted based on the analysis.

System and method for compensating for SDRAM signal timing drift through periodic write training

Micro-idle power in a subsystem of a portable computing device may be actively managed based on client voting. Each client vote may include a client activity status indication and a client latency tolerance indication. Votes are aggregated to provide an aggregate client latency tolerance, which may be used to obtain a set of micro-idle time values. Micro-idle timers in the subsystem may be set to associated micro-idle time values. The micro-idle timers determine whether one or more of the micro-idle time values have elapsed. A power management policy associated with each micro-idle time value determined to have elapsed may be applied to a portion of the subsystem.

Active power management in a computing device subsystem based on micro-idle duration

Systems and methods are disclosed for configuring dynamic random access memory (DRAM) in a personal computing device (PCD). An exemplary method includes providing a shared command access (CA) bus in communication with a first DRAM and a second DRAM. A first command from a system on a chip (SoC) is received at the first DRAM and the second DRAM. A decoder of the first DRAM determines whether to mask a mode register write (MRW) in response to the received first command. A second command containing configuration information is received vie the shared CA bus at the first DRAM and the second DRAM. Responsive to the determination by the decoder of the first DRAM, the received MRW is either ignored or implemented by the first DRAM.

Systems and methods for individually configuring dynamic random access memories sharing a common command access bus

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San Diego, CA, United States of America

Farrukh Aquil