IT Home News on March 6, JEDEC, the solid-state technology association, today officially released the JESD239 GDDR7 video memory standard (Graphics Double Data Rate), JESD239 GDDR7 provides twice the bandwidth of GDDR6, up to 192 GB S per device.
According to reports, the JESD239 GDDR7 is the first JEDEC standard DRAM to use a Pulse Amplitude Modulation (PAM) interface for high-frequency operation. Its PAM3 interface improves the signal-to-noise ratio (SNR) for high-frequency operation while improving energy efficiency. By using 3 levels (+1,0,-1) to transmit 3 bits on 2 cycles, while the traditional NRZ (non-return-to-zero) interface transmits 2 bits on 2 cycles, PAM3 provides a higher data transfer rate per cycle, resulting in improved performance.
Other advanced features of the JESD239 GDDR7 include:
A core-independent LFSR (Linear Feedback Shift Register) training mode with eye masking and error counters improves training accuracy while reducing training time.
The number of independent channels has doubled from 2 in GDDR6 to 4 in GDDR7.
Supports 16 Gbit to 32 Gbit density, including support for 2-channel mode to double system capacity.
Meet the market demand for RAS (reliability, availability, serviceability) by incorporating the latest data integrity features, including on-chip ECC with real-time reporting (ODECC), data poisoning, error checking and sanitization, and command address parity with command blocking (CAPARBLK).
"The JESD239 GDDR7 marks a significant step forward in high-speed memory design," said Mian Quddus, Chairman of the Board of Directors of JEDEC. With the shift to PAM3 signaling, the memory industry has a new way to scale the performance of GDDR devices and push for the evolution of high-performance applications. ”
"GDDR7 is the first GDDR to not only focus on bandwidth, but also address the needs of the RAS market by incorporating the latest data integrity features that enable GDDR devices to better serve existing markets such as cloud gaming and computing, and extend to AI," said Michael Litt, chair of the JEDEC GDDR subcommittee. ”
IT Home learned from the announcement that AMD, Micron, Nvidia, Samsung, and SK hynix have all expressed support for the standard. In addition, both Samsung and Micron have development plans for the next generation of GDDR7 modules. Samsung is aiming for 32 Gbps speeds, achieving 16x performance improvement; And Micron is also targeting 24 GB+ 32 Gbps chips. Micron also said in its latest roadmap that by 2026, it will launch up to 36 Gbps and 24Gb+ graphics memory chips.