Abstract: DDR PHY interface bit error testing and training is provided for Double Data Rate memory systems. An integrated circuit comprises a bit error test (BERT) controller that provides a bit pattern; and a physical interface having a plurality of byte lanes. A first byte lane is connected by a loopback path to a second byte lane and the BERT controller writes the bit pattern that is obtained using the loopback path to evaluate the physical interface. The evaluation comprises (i) a verification that the bit pattern was properly written and read; (ii) a gate training process to position an internal gate signal; (iii) a read leveling training process to position both edges of a strobe signal; and/or (iv) a write bit de-skew training process to align a plurality of bits within a given byte lane.

Abstract: DDR PHY interface bit error testing and training is provided for Double Data Rate memory systems. An integrated circuit comprises a bit error test (BERT) controller that provides a bit pattern; and a physical interface having a plurality of byte lanes. A first byte lane is connected by a loopback path to a second byte lane and the BERT controller writes the bit pattern that is obtained using the loopback path to evaluate the physical interface. The evaluation comprises (i) a verification that the bit pattern was properly written and read; (ii) a gate training process to position an internal gate signal; (iii) a read leveling training process to position both edges of a strobe signal; and/or (iv) a write bit de-skew training process to align a plurality of bits within a given byte lane.

Abstract: A core including a write logic IP block, a read logic IP block, a master delay IP block and an address and control IP block. The write logic IP block may be configured to communicate data from a memory controller to a double data rate (DDR) synchronous dynamic random access memory (SDRAM). The read logic IP block may be configured to communicate data from the double data rate (DDR) synchronous dynamic random access memory (SDRAM) to the memory controller. The master delay IP block may be configured to generate one or more delays for the read logic IP block. The address and control logic IP block may be configured to control the write logic IP block and the read logic IP block. The core is generally configured to couple the double data rate (DDR) synchronous dynamic random access memory (SDRAM) and the memory controller.

Abstract: A method for calibrating a data valid window including the steps of: (A) setting a base delay of one or more datapaths to a predetermined value, (B) determining an optimum offset delay value for each of the one or more datapaths based upon actual memory accesses and (C) delaying a read data strobe signal based upon the base delay and the optimum offset delay value for each of the one or more datapaths.

Abstract: A method for calibrating read data strobe gating including the steps of: (A) performing a coarse timing adjustment configured to determine a coarse delay setting that produces invalid data, (B) performing a medium timing adjustment configured to adjust a medium delay setting and the coarse delay setting until valid data is detected, (C) performing a fine timing adjustment configured to adjust the medium delay setting and a fine delay setting until valid data is detected and (D) adding one-half cycle to a gating delay determined by the coarse, the medium and the fine delay settings.

Abstract: An apparatus comprising a first circuit, a second circuit and a third circuit. The first circuit may include a plurality of first multiplexers and one or more second multiplexers configured to generate a first intermediate enable signal in response to (i) an input enable signal, (ii) a first clock signal operating at a first data rate and (iii) a plurality of first select signals. The plurality of first multiplexers each present an output to each of the one or more second multiplexers. The second circuit may be configured to generate a second intermediate enable signal in response to (i) the first intermediate enable signal, (ii) a second clock signal operating at a second data rate and (iii) a second select signal. The third circuit may be configured to generate a third intermediate enable signal in response to (i) the second intermediate enable signal, (ii) a control input signal and (iii) a third select signal. The third intermediate enable signal may be configured to control a read operation of a memory.

Abstract: An apparatus comprising a first circuit and a second circuit. The first circuit may be configured to read and write data through a plurality of input/output lines. The second circuit may include a plurality of sections. Each section may be configured to present a control signal to a load output line and receive a feedback of the control signal through a load input line. The load input line and the load output line of each of the sections may be connected to a load circuit configured to match a respective memory load connected to each of the plurality of input/output lines.

Abstract: A macro cell is provided for an integrated circuit design having an input-output (IO) region with a plurality of IO buffer cells physically dispersed with other cells in IO slots along an interface portion of the IO region. The macro cell includes a plurality of macro cell IO signal slots that are physically dispersed so as to substantially align with the IO buffer cells in the interface portion. The macro cell also includes an interface definition having a plurality of interface IO signal nets, which are routed to corresponding ones of the plurality of macro cell signal slots. The macro cell is adapted to be instantiated as a unit in the integrated circuit design.