Expect a Memory Revolution in 2020—It’s a Big Leap from DDR4 to DDR5

Double data rate five (DDR5), the new generation of synchronous dynamic random-access memory (SDRAM), will provide higher performance, larger bandwidth, faster data transfer, and low power consumption.

The leap from DDR4 and DDR5 is no incremental development. We're looking at a leap from standard frequencies of 2400 MHz to 4800 MHz. According to Samsung, DDR5 memory can send and receive double the data signals in one clock cycle as DDR4, promoting more capacity and faster transfer rates. 

The goal here is to support heavily trafficked datacenters, which are especially burdened because of stay-at-home orders.

 

Chart comparing key specifications of DDR4 and DDR5. Image used courtesy of SK hynix

 

DDR5 is not here yet, but many suppliers have made definitive moves for this technology to unfold over the next two years. 

 

How Does DDR5 Differ From DDR4?

SK hynix recently released a report in which they outlined several anticipated changes from DDR4 to DDR5. 

1. DDR5's memory access is double that of DDR4's because of its architecture, which has 32banks1 structure based on 8 bank groups. 
2. DDR5 also features a burst length (BL)2 of 16 whereas DDR4's is 8. 
3. Unlike DDR4, which can't perform other operations while refreshing, DDR5 allows concurrent bank access with a "Same Bank Refresh" function.
4. DDR5 features a Decision Feedback Equalization (DFE) circuit that slashes reflective noise during a channels' operation, boosting the speed per pin.
5. DDR5 has an operating voltage of 1.1 V while DDR4 has an operating voltage of 1.2 V; this change represents a 20% reduction in power consumption per bandwidth.

 

Infographic of the advantages of DDR5. Image (modified) used courtesy of SK hynix

 

Micron: the Trailblazer of DDR5

Micron has been redefining memory and storage solutions for the last 40 years and was among the first suppliers to roll out promises of DDR5 in January. Micron’s stated purpose for the next-gen SDRAM was to relieve data center servers. They are also targeting mobile devices. 

 

Micron’s LPDDR5 DRAM for mobile apps is built for 5G. Image used courtesy of Micron

 

Micron’s low power (LP) DDR5 DRAM will be integrated into Motorola’s new edge+ smartphone, bringing the "full potential of the 5G experience" to consumers. Motorola says the new smartphone will have a high-resolution camera, bold display, and high bandwidth for streaming entertainment.

The LPDDR5's high speed and low power consumption will allow mobile and automotive devices to keep up with AI technology, autonomous driving, 5G networks, and camera innovations. 

 

Renesas Supports DDR5 Modules With Sensor

Renesas Electronics Corporation recently announced a new precision temperature sensor, the TS5111, built specifically to support DDR5 memory modules. Renesas’s TS5111 sensor will provide warning flags that will exercise memory refresh, a crucial step for chip manufacturers. Without memory refresh function, the stored data would eventually be lost. 

The sensor measures at 0.8 mm x 1.3 mm, features a data transfer rate of up to 12.5 MHz, and includes a 1.8 V and 1.1 V power supply input.

 

Renesas’s portfolio of memory interface products includes DDR5 RCD, PMIC, SPD Hub, and TS devices. Image used courtesy of Renesas

 

DDR5 has the key characteristics fit for an aerospace-bound sensor: precision, low power, and a small footprint. Aeropropulsion and crew vehicles require such a sensor to accurately measure and monitor fluctuations in temperature. 

 

Keysight Releases Design and Test Tools for DDR5

Keysight Technologies is also paving a path for more widespread DDR5 adoption. Keysight recently introduced "the world’s first design and test workflow solution" for DDR5 memory solutions at DesignCon 2020. The new solution is said to reduce product development time for DDR5 dynamic random-access memory (DRAM) systems.

Because DDR5 runs at double the data rate of DDR4, hardware designers face a shrinking design margin in which they can address jitter, crosstalk, and reflection. DDR5 DRAM recovers these heavily distorted signals with decision feedback equalization (DFE), which are unlike conventional measurement and simulation procedures of previous DDR iterations.

 

Keysight's DDR5 complete design and test solution. Image used courtesy of Keysight Technologies

 

Keysight aims to reduce downtime and allow developers to meet product deadlines by introducing new transmitter test tools, tests for loopback bit-error-rate (BER), and logic analysis for debugging DDR5 traffic transactions.

 

Samsung Levels Up from DDR4 to DDR5

With DDR5, Samsung developers aim to restructure the memory’s architecture, making it capable of handling bandwidth-per-core requirements of modern-day CPUs.

 

Samsung’s DDR5 allows up to 4,800 Mbps in data transfer. Image used courtesy of Samsung

 

The DDR5 synchronous dynamic random-access memory (SDRAM) is designed to help the overwhelming workloads that are present in data center servers. Samsung says DDR5 SDRAM increases reliability, availability, and serviceability (RAS) that typical data centers require.

Samsung plans to integrate DDR5 with its latest TSV-8 layer technology, a challenging packaging method that will utilize DDR5’s ability to contain twice the number of stacks compared to DDR4. 

 

What's Next for DDR5?

In a report cited in SK hynix's coverage of DDR5, the International Data Corporation (IDC) claims that DDR5 will account for "22% of the total DRAM market in 2021 and 43% in 2022." SK hynix has announced that it plans to ramp up DDR5 memory chip production this year.

Samsung’s DDR5/LPDDR5 will also hit mass production within the second half of this year heading into 2021. 

 

Samsung’s 4th gen 10nm-class (1a) EUV-based 16Gb DDR5/LPDDR5 mass production set to begin in 2021. Image used courtesy of Samsung

 

The company claims it will strengthen its collaboration with leading IT customers and semiconductor vendors as it accelerates the transition from DDR4 to DDR5 for highly-anticipated mobile devices. While we won't see the full effects of this shift from DDR4 to DDR5 for another few months, these outlooks show promise that we're in store for a memory revolution.

 

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Do you find yourself constrained by current SDRAM parameters? How do you work around those limitations? Share your experiences in the comments below.