Development Of High-Speed Storage Card Based On PXIe Bus

In the field of the current test, with the continuous development of automatic test system, the data storage requirements are also put forward the new challenges. Data transfer rate can be up from hundreds of MB to GB/s, data storage capacity is as high as hundreds of GB or TB level. This paper has developed a solid state memory card, based on PXIe bus and eMMC memory chips.This paper presents a design of memory card, based on analyzing of technical requirements, application situation and the existing technical reserves. This design uses PCIe and USB3.0 as the data transfer interface, and uses eMMC as storage medium.This design uses FPGA of Cyclone V GX series as the main controller, which has the Hard IP for PCIe and the IP core of SGDMA, which makes it easier to realize chain DMA. The Samsung 32 GB e MMC chip is used as the storage chip. Eight parallel use of it can increase the capacity up to 256 GB. This design uses four DDR2 SDRAM to make up with cache. The capacity of cache is 2GB. The theory of speed is 3.2GB/s, which solves the problem of the mismatch between the memory chip and the data transmission interface.Due to high frequency, when designing PCB, this paper first does the simulation of the signal integrity by using the model of IBIS in Allegro PCB SI software, then does the simulation for the signals of DDR and e MMC, to ensure signal transmission meeting requirment in theory, which saves designing time. When designing logic, this paper uses the method of high-speed logic. To communicate with external device, the paper uses source-synchronous constraining and analyzing, and adjusts the phase between clock and data to ensure the data valid window. By comparing the effects of different logic implementation methods on the timing of the same function, the design code is optimized to ensure that the logic operation is stable.Test results show that, this storage card can realize continuous reading and writing in 600MB/s. it satisfied the design requirement. It accumulates valuable experience for the following design and further development, and has a high value of application.