• Skip to primary navigation
  • Skip to main content
  • Skip to footer
  • English
  • Investor Relations
  • Resource Library
  • Newsroom
  • Blog
  • Careers
  • Support Center
Rambus Logo

Rambus

At Rambus, we create cutting-edge semiconductor and IP products, spanning memory and interfaces to security, smart sensors and lighting.

  • Products
      • All
          • Memory Interface Chips
          • DIMM Chipsets
          • DDR5 DIMM Chipset
          • DDR4 NVRCD
          • DDR4 Register Clock Driver
          • DDR4 Data Buffer
          • CXL Memory Interconnect Initiative
          • Interface IP
          • Memory PHYs
          • GDDR6 PHY
          • HBM3 PHY
          • HBM2E PHY
          • DDR4 PHY
          • More…
          • SerDes PHYs
          • PCIe 6.0 PHY
          • PCIe 5.0 PHY
          • 32G C2C PHY
          • 32G PHY
          • 28G PHY
          • More…
          • Digital Controllers
          • Memory Controllers
          • CXL & PCI Express Controllers
          • MIPI Controllers
          • Video Compression and Forward Error Correction Cores
          • Security IP
          • Root of Trust Solutions
          • Security Protocol Engines
          • Inline Cipher Engines
          • Crypto Accelerator Cores
          • DPA Countermeasures
          • Software Protocols & Crypto Toolkits
          • Anti-Counterfeiting
          • Provisioning and Key Management
      • Memory Interface Chips
        • DIMM Chipsets
          • DDR5 DIMM Chipset
          • Non-Volatile DDR4 Registering Clock Driver
          • DDR4 Register Clock Driver
          • DDR4 Data Buffer
          • DDR3 Register Clock Driver
          • DDR3 Isolation Memory Buffer
        • CXL Memory Interconnect Initiative

        • Made for high speed, reliability and power efficiency, our DDR3, DDR4, and DDR5 DIMM chipsets deliver top-of-the-line performance and capacity for the next wave of computing systems. Learn more about our Memory Interface Chip solutions
      • Interface IP
          • Memory PHYs
            • GDDR6 PHY
            • HBM3 PHY
            • HBM2E PHY
            • DDR4 PHY
            • DDR4 Multi-modal PHY
            • DDR3 PHY
          • SerDes PHYs
            • PCIe 6.0 PHY
            • PCIe 5.0 PHY
            • PCIe 4.0 PHY
            • 32G C2C PHY
            • 32G PHY
            • 28G PHY
            • 16G PHY
            • 12G PHY
            • 6G PHY
          • Digital Controllers
            • HBM3 Controller
            • HBM2E Controller
            • GDDR6 Controller
            • LPDDR5 Controller
            • CXL 2.0 Controller
            • PCIe 6.0 Controller
            • PCIe 5.0 Controller
            • MIPI CSI-2/DSI-2 Controllers
            • Video Compression and Forward Error Correction Cores
            • More…

        • With their reduced power consumption and industry-leading data rates, our line-up of memory interface IP solutions support a broad range of industry standards with improved margin and flexibility. Learn more about our Interface IP solutions
      • Security IP
          • Root of Trust Solutions
          • Security Protocol Engines
            • MACsec Engines
            • IPsec, TLS, SSL Multi-Protocol Engines
            • High Speed Public Key Accelerator
          • Inline Cipher Engines
          • Crypto Accelerator Cores
            • DPA Resistant Cores
            • Basic Crypto Blocks
          • Anti-Counterfeiting
            • CryptoFirewall Cores
            • Circuit Camouflage Technology
          • DPA Countermeasures
            • DPA Resistant Cores
            • DPA Resistant Software Libraries
            • DPA Workstation Platform
          • Software Protocols & Crypto Toolkits
            • IPsec Toolkit
            • FIPs Cryptographic Libraries
            • MACsec Toolkit
            • IoT Security Framework
          • CryptoMedia
            • Content Protection Core
            • Content Protection Services
          • Provisioning and Key Management
            • CryptoManager Provisioning
            • CryptoManager Device Key Management

        • From chip-to-cloud-to-crowd, Rambus secure silicon IP helps protect the world’s most valuable resource: data. Securing electronic systems at their hardware foundation, our embedded security solutions span areas including root of trust, tamper resistance, content protection and trusted provisioning. Learn more about our Security IP offerings
  • Markets
      • AI & Machine Learning
        • Speed and Security for the Artificial Intelligence & Machine Learning Revolution
          • Products
          • SerDes PHYs
          • Memory PHYs
          • Digital Controllers
          • Memory Interface Chips
          • Root of Trust
          • Crypto Accelerator Cores
          • Protocol Engines
          • Provisioning and Key Management
          • AI & Machine Learning
      • Automotive
        • Providing Performance & Security for the Connected Car
          • Products
          • Memory PHYs
          • SerDes PHYs
          • Digital Controllers
          • Root of Trust
          • PKE Engine
          • MACsec Engines
          • Crypto Accelerator Cores
          • Provisioning and Key Management
          • Explore Automotive
      • Data Center
        • Optimizing capacity, connectivity and capability of the cloud
          • Products
          • SerDes PHYs
          • Memory PHYs
          • Digital Controllers
          • Memory Interface Chips
          • Root of Trust
          • MACsec Engines
          • Software Protocols
          • Provisioning and Key Management
          • See Data Center
      • Edge
        • Catching a tidal wave of data
          • Products
          • Memory PHYs
          • SerDes PHYs
          • Digital Controllers
          • Root of Trust
          • Crypto Accelerator Cores
          • Protocol Engines
          • Software Protocols
          • Discover Edge
      • Government
        • Securing Mission-critical Systems
          • Products
          • Root of Trust
          • Protocol Engines
          • Anti-Tamper Cores
          • Provisioning and Key Management
          • DPA Workstation Platform
          • SerDes PHYs
          • Memory PHYs
          • Digital Controllers
          • See Government
      • IoT
        • Making IoT Data Safe & Fast
          • Products
          • Root of Trust
          • TLS Toolkits
          • Provisioning and Key Management
          • Memory PHYs
          • SerDes PHYs
          • Digital Controllers
          • Explore IoT
  • Resources
    • Inventions
    • Buying Guide
    • Resource Library
      • Webinars
      • Product Selector
  • About
      • Corporate Overview
      • Leadership
      • Inventors
      • Careers
      • Locations
      • Investor Relations
      • Newsroom
      • Blog
      • Events
      • Partnerships
      • Certifications
      • Corporate Responsibility
      • Contact
Home > Inventions > Memory + Interfaces > Fully Differential Memory Architecture

Fully Differential Memory Architecture

As data rates continue to increase, signal and power integrity are increasingly difficult to maintain in memory systems with single-ended signaling topologies. To enhance signal integrity and noise immunity across all communications between the memory PHY and the DRAM devices, Rambus implemented a Fully Differential Memory Architecture (FDMA) using a point-to-point topology, for data, clock, and command/address (C/A) channels. FDMA inherently reduces interference noise from simultaneous switching outputs (SSO) and crosstalk. Further, it reduces the EMI that would otherwise be generated in a single-ended system operating at the same data rate or frequency. With these advantages, FDMA enables very high-speed data transmission supported by full-speed operation of C/A channels.

  • Enables low-power, high-performance memory systems
  • Simplifies system design
  • Increases system reliability through improved noise immunity

What is a Fully Differential Memory Architecture?

Fully Differential Memory Architecture example - Differential signaling circuit diagram

Differential signaling uses two wires for each signal (bit). A complementary signal is transmitted on one line or the other using a small DC current. The current is passed through a resistor on each line to generate a voltage, the difference being measured at the receiver. Depending on the polarity, the signal is interpreted as a “1” or “0”. SSO noise, a function of the cumulative value of the total amount of current change, is reduced because the same amount of current is generated regardless of the bit’s value.

A further advantage of differential signaling is that for a given voltage at the transmitter, twice the voltage difference is measured at the receiver (the difference in voltage between the two wires in the current loop). This compares with single-ended signaling that exhibits the same voltage at the transmitter and receiver (the difference between the voltage on the wire and ground). Twice the voltage at the receiver means it takes twice as much noise to exceed the threshold of a valid voltage level.

In addition, differential signaling has superior noise immunity when compared to single-ended signaling due to its inherent common mode noise rejection. Any voltage noise that couples into one wire of a pair is likely to couple into the other. Because the difference between the two signals is measured at the receiver, the common noise components are effectively cancelled out. In addition to being less susceptible to noise, differential signal pairs create less EMI than single-ended signals. This is because changes in signal level in the two wires create opposing electromagnetic fields that superimpose and cancel each other out, reducing crosstalk and spurious emissions.

Who Benefits?

FDMA offers a scalable architecture for delivering memory system bandwidth performance up to and beyond one terabyte per second. It supports a lower operating power at any given data rate since lower voltage levels than those required in a single-ended system can be used to maintain sufficient signal integrity. Further, FDMA simplifies overall system design and increases reliability by harnessing differential signaling advantages of superior noise immunity and lower EMI generation.

Footer

About

  • Corporate Overview
  • Leadership
  • Careers
  • Locations
  • Investor Relations
  • News
  • Corporate Responsibility

Products

  • Memory PHYs
  • SerDes PHYs
  • Digital Controllers
  • Server DIMM Chipsets
  • Root of Trust Solutions
  • Provisioning and Key Management
  • Protocol Engines
  • Crypto Accelerator Cores
  • Software Protocols
  • DPA Countermeasures
  • Anti-Counterfeiting
  • CryptoMedia

Markets

  • AI & Machine Learning
  • Automotive
  • Data Center
  • Edge
  • Government
  • IoT
  • Pay TV

Resources

  • Resource Library
  • Webinars
  • Inventions
  • Buying Guide
  • Contact

Copyright © 2023 Rambus.com. All Rights Reserved. Privacy Policy | Trademark & Guidelines

  • Facebook icon
  • Twitter icon
  • YouTuve icon
  • LinkedIn icon
  • Blog icon