Ddr sdram controller pdf

We created such basic system using a xyloem board as part of our validation process. The double data rate architecture is essentially a 2nprefetch architecture with an interface designed to transfer two data words per clock cycle at the io pins. Ddr sdram, as the first generation of ddr memory, the prefetch buffer is 2bit, which is the double of sdr sdram. Ddr sdram controller architecture ddr sdram controller module receives addresses and control signals from the bus master. Double data rate, column address strobe cas, synchronous dynamic ram. The ddr sdram controller is located in between the ddr sdram and bus. Double data rate interfaces advantages time of flight clock skew pin count bandwidth disadvantage synchronization clk data sdr d0 d1 d2 d3 d4 d5 d6 d7 ddr clk. Ddr sdram, also retroactively called ddr1 sdram, has been superseded by ddr2 sdram, ddr3 sdram and ddr4 sdram. The ddr sdram controller architecture is shown in figure 2. Double data rate ddr sdram specification, jedec standard jesd79e, may 2005. As a result, more and more designers are turning to doubledatarate ddr sdram interfaces such as ddr, ddr2, and.

Functional description the ddr sdram controller block diagram, illustrated in figure 1, consists of four functional modules. All signals are synchronous to the system clock and outputs are registered at the output of the sdram controller core. Unfortunately, they are not as easy to control as static memories, so an sdram controller is often used. The ddr3 sdram architecture is based on prefetch architecture with the design of two data words over clock cycle. Dimm implementations have expanded from unregistered dimms to include registered dimms and fbdimms fully. The work concentrates on the relative study of two memory controllers viz. Ddr3 sdram is the third generation of the ddr sdram family, and offers improved power, higher data bandwidth, and enhanced signal quality with multiple ondie termination odt selection and output driver impedance control while maintaining partial backward compatibility with the existing ddr2 sdram standard. The ddr sdram uses a double data rate architecture to achieve highspeed operation. The component consists of a ddr sdram controller core with configurable options and. Select device instantiate phy and controller in a quartus ii project. Double data rate synchronous dynamic randomaccess memory, officially abbreviated as ddr sdram, is a double data rate ddr synchronous dynamic randomaccess memory sdram class of memory integrated circuits used in computers. Anup et al, ijcsit international journal of computer. Using the sdram memory on alteras de2 board with verilog. Mpc603e series e300 core superscalar architecture datasheet search, datasheets, datasheet search site for electronic components and semiconductors, integrated circuits, diodes and other semiconductors.

The ddr sdram is an enhancement to the traditional. In this paper, the implementation has been done in verilog hdl by using xilinx ise 9. The project also contains a simple push button interface for testing on the dev board. A low power ddr sdram controller design international journal. The core accepts commands using a simple local interface and translates them to the command sequences required by mobile. The controller generates command signals and based on these signals the data is either read or written to a particular memory location. Using the sdram memory on alteras de2 board with verilog design. This is a very a simple sdram controller which works on the de0 nano. The ddr synchronous dynamic random access memory sdram controller implements the controls for an external memory bus interface using the dual data rate ddr version 2 protocol and electrical interface that adheres to the jedec standard jesd792f nov. What is the difference between sdram, ddr1, ddr2, ddr3 and. Design and implementation of ddr sdram controller using. Microsoft powerpoint 050929 an introduction to sdram and memory controllers. Xilinx xapp709 ddr sdram controller using virtex4 fpga.

The detailed design and operation of its individual sub blocks is described. For our controller, we target what is probably the simplest sdram available. The phy layer consists of me mory initialization logic, and addresscommanddata io. The memory controller accepts commands using local interface and translates them to the command sequences required by. A single read or write access for the ddr sdram effectively consists of a single 2nbitwide, one. Our work will focus on asic design methodology of double data rate ddr sdram controller that is located between the ddr sdram and bus master.

Newer variants of sdram are ddr or ddr1, ddr2 and ddr3. Dram tutorial isca 2002 bruce jacob david wang university of maryland since drams inception, there have been a stream of changes to the design, from fpm to edo to burst edo to sdram. The operations of ddr sdram controller is to simplify the sdram command interface to the standard system read write interface and also optimization of the access time of readwrite cycle. Pdf implementation of ddr sdram controller using verilog. Synchronous dram sdram has become a mainstream memory of choice in design due to its speed. In this paper, the overall architecture of the ddr4 sdram controller is proposed. Ddr simply use sophisticated circuit techniques to achieve high speed. The ddr3 sdram is the nextgeneration ddr sdram memory technology which features faster speed, mitigated sso, and reduced routing due. Keywords ddr sdram controller, readwrite data path, cadence rtl compiler. The new controller enables virtex6 users to capitalize on the improved capacity, performance and power efficiency of the latestgeneration ddr sdram technology. Sdram synchronous dram is a generic name for various kinds of dynamic random access memory dram that are synchronized wit. To add the sdram, in the window of figure 3 select memories and memory controllers sdram sdram controller and click add. A summary of the ddr memory controller standardwait, there isnt one.

The altmemphy megafunction is an interface between a memory controller and the. In particular, sdrams are very popular memories due to their high speed and low cost. Ddr and ddr2 sdram controller with altmemphy ip user. Design and implementation of high speed ddr sdram controller. Lattice semiconductor ddr sdram controller 2 since the ddr sdram controller takes care of activatingprecharging the banks, user only needs to issue simple readwrite commands. The ddr synchronous dynamic ram is an enhancement to the conventional sdram running at bus speed over 75mhz. Mobile ddr sdram controller core northwest logics mobile double data rate ddr sdram controller core is designed for use in applications requiring high memory throughput, high clock rates and full programmability. Keystone architecture ddr3 memory controller users guide literature number. The ddr sdram controller is located in between the ddr sdram and bus master. Coreddr ddr sdram controller product summary intended use ddr sdram controller for standard sdram chips and dimms key features interfaces to external ram supports up to 1024 mb of memory synchronous interface highperformance access logic allows cascading of read and write requests enabling up to 100% throughput. Ddr3 sdram 1 use a double data rate to achieve a high speed synchronous dynamic random access memory operations with eight register bank 2.

The fact that the sdram controller is dualported makes the design straightforward the pcfx2 is the writing agent, and the video controller is the reading agent. Ddr sdram controllers are faster and efficient master. March 2009 altera corporation ddr and ddr2 sdram controller compiler user guide the performance of the entire system and in general the ddr or ddr2 sdram controller depends upon the number of masters and slaves connected to the avalon memorymapped avalonmm interface, which degrades as the number of masters and slaves connected to it. You can replace the ddr or ddr2 sdram controller encrypted control logic in the example design with your own custom logic, which allows.

Table shows maximum performance results for the ddr and ddr2 sdram highperformance controllers using the quartus ii software, version 9. Ddr sdram memory controller ahb core memory controller dqeven dqodd ahb buss ddr sdram command write data read data command write data command read data read data. Design and simulation of ddr3 sdram controller for high. Ddr controller provides a synchronous command interface to the ddr sdram memory along with several control signals. Designware enhanced universal ddr memory controller. The basic operations of ddr sdram controller are similar to that of sdr single data rate sdram.

It supports data transfers on both edges of each clock cycle, effectively doubling the. Its primary benefit is the ability to operate the external data bus twice as fast as ddr sdram. Pdf irjet design and vlsi verification of ddr sdram. Functional diagram of ddr sdram controller 2 the memory controller has three modules. Ddr sdram controller megacore function user guide gettingabout this core about this core the ddr sdram controller is optimized for altera cyclone, stratix, 1 stratix gx, and apex ii devices. The controller consists of a high performance timing and control state machine.

Altera corporation ddr sdram controller white paper 3 ddr sdram controller description ddr sdram controller interface signals the ddr sdram controller interface signals are shown in table 2 interface signals. Ddr sdram memory controller reference design xapp851 v1. On the surface, a ddr sdram component is simply a readwrite memory. Design and vlsi implementation of ddr sdram controller for. The lattice double data rate ddr3 synchronous dynamic random access memory sdram controller is a generalpurpose memory controller that interfaces with industry standard ddr3 memory devicesmodules compliant with jesd793, ddr3 sdram standard, and provides a generic command interface to user applications.

Xilinx xapp851 ddr sdram controller using virtex5 fpga. Both sdram and ddr ram are memory integrated circuits used in computers. It has a user interface at one side and the memory at the other side. Pdf asic implementation of ddr sdram memory controller. Design guidelines for implementing ddr and ddr2 sdram interfaces in cyclone iii devices figure 1. The ddr and ddr2 sdram controller with altmemphy intel fpga ip core work in conjunction with the altmemphy physical interface ip function. The msc711x memory controller supports double data rate synchronous dynamic random access memory ddr sdram devices, which are designed to be a high data rate migration path from the standard single data rate sdr memory devices. Sdram synchronous dram, ddr double data rate sdram, ddr2 double data rate 2 sdram, and ddr3 double data rate 3 sdram. In reality, however, modern ddr sdrams are complex devices. The transition from ddr4 to ddr5 represents far more than a typical ddr sdram generational change. A summary of the ddr memory controller standardwait.

Abstract this project work is a working implementation of high speed ddr double data rate sdram controller. Second generation of ddr memory ddr2 scales to higher clock. Implementation of ddr sdram controller using verilog hdl. Therefore only ddr sdram controller is described in following sections. The controllers has similar architecture is shown in fig. The ddr sdram memory controller is a configurable high performance memory controller for systems requiring access to external ddr sdram memory devices or ddr dimm modules with lowest latency and highest throughput. The advanced features available in these devices allow you to interface direct ly to ddr sdram. Ddr and ddr2 sdram controllers with altmemphy ip user guide 1. Deepali sharma et al, ijcsit international journal of. Ddr3 runs at a frequency between 800mhz to 1600 mhz. Design flow for implementing external memory interfaces in cyclone iii devices note to figure 1. Xperts corner improving ddr sdram efficiency with a. To perform more operations per clock cycle ddr sdram uses double data rate architecture. Second generation of ddr memory ddr2 scales to higher clock frequencies.

Pdf synchronous dram sdram has become a mainstream memory of choice in design due to its speed, burst access and pipeline. Pdf design and vlsi implementation of ddr sdram controller. Fpga implementation of double data rate ddr sdram controller. Now days, ddr sdram double data rate synchronous dynamic random access memory has become the most popular class of memory used in computers due to its high speed, burst access and pipeline feature. The designware enhanced universal memory controller umctl2 is fully configurable controller that allows designers to generate a ddr controller that is optimized for latency, bandwidth, and area. This application note examines the basics of ddr, provides general boardlevel design guidelines for using the msc711x. Ddr5 demonstrates a major step forward that has completely overhauled the overall ddr architecture with one primary goal.