editor's blog
Subscribe Now

Keeping DDR Performance Fresh

DDR memory timing is tricky business. Especially with later versions of the standard, the timing for each memory on a module has to be carefully determined; there’s no such thing as just issuing a read or write to all the chips together. A further problem, however, is that the timing is subject to change based on a number of factors, including environmental conditions and wear-out.

Some companies address this by doing a power-up calibration that involves reading and writing to figure out the optimal timing. But things can still drift as the system warms up or the box gets moved into the sun or the environment changes for any of a number of other reasons.

Uniquify, a company whose business has morphed from ASIC design services into an IP company (with further evolution underway) has earned a patent on dynamic recalibration – the ability to keep tuning the timing during use. The prior barrier had been the fact that writing to the memory for calibration purposes is destructive. That’s not a problem at startup, before anyone has started using memory, but while the system is running, the application has control of the memory, and there is little appetite for setting a bit of it aside for use only by calibration.

Uniquify’s approach was to use application memory, but copy and store the current contents of the calibration location, do the calibration, and then replace the contents so that the application never notices it missing. The timing of this recalibration can be set to coincide with refresh or at some other designer-defined interval.

The calibration looks both for drift in the timing window as well as changes to the width of that window. Each recalibration finds the edges of the window and recenters the strobe. But if the window closes, then a specific error is flagged.

You can find out more in their latest release.

Leave a Reply

featured blogs
Sep 22, 2021
3753 Cruithne is a Q-type, Aten asteroid in orbit around the Sun in 1:1 orbital resonance with the Earth, thereby making it a co-orbital object....
Sep 21, 2021
Placing component leads accurately as per the datasheet is an important task while creating a package footprint symbol. As the pin pitch goes down, the size and location of the component lead play a... [[ Click on the title to access the full blog on the Cadence Community si...
Sep 21, 2021
Learn how our high-performance FPGA prototyping tools enable RTL debug for chip validation teams, eliminating simulation/emulation during hardware debugging. The post High Debug Productivity Is the FPGA Prototyping Game Changer: Part 1 appeared first on From Silicon To Softw...
Aug 5, 2021
Megh Computing's Video Analytics Solution (VAS) portfolio implements a flexible and scalable video analytics pipeline consisting of the following elements: Video Ingestion Video Transformation Object Detection and Inference Video Analytics Visualization   Because Megh's ...

featured video

Digital Design Technology Symposium

Sponsored by Synopsys

Are you an SoC designer or manager facing new design challenges driven by rapidly growing and emerging vertical segments for HPC, 5G, mobile, automotive and AI applications?

Join us at the Digital Design Technology Symposium.

featured paper

Detect. Sense. Control: Simplify building automation designs with MSP430™ MCU-based solutions

Sponsored by Texas Instruments

Building automation systems are critical not only to security, but worker comfort. Whether you need to detect, sense or control applications within your environment, the right MCU can make it easy. Using MSP430 MCUS with integrated analog, you can easily develop common building automation applications including motion detectors, touch keypads and e-locks, as well as video security cameras. Read more to see how you can enhance your building automation design.

Click to read more

featured chalk talk

Thermocouple Temperature Sensor Solution

Sponsored by Mouser Electronics and Microchip

When it comes to temperature monitoring and management, industrial applications can be extremely demanding. With temperatures that can range from 270 to 3000 C, consumer-grade temperature probes just don’t cut it. In this episode of Chalk Talk, Amelia Dalton chats with Ezana Haile of Microchip technology about using thermocouples for temperature monitoring in industrial applications.

More information about Microchip Technology MCP9600, MCP96L00, & MCP96RL00 Thermocouple ICs