Embedded Systems Conference
Breaking News
Comments
Oldest First | Newest First | Threaded View
rick merritt
User Rank
Author
Memory stacks
rick merritt   11/5/2013 2:02:22 PM
NO RATINGS
I am hungry to hear what folks are doing with Micron and SK Hynix memory cubes/stacks. How is this different from 2.5-D stacks with a processor and memory on an interposer? What are the trade offs?

krisi
User Rank
Author
0.064mm2 sram cell
krisi   11/5/2013 4:18:18 PM
NO RATINGS
Amazing small cell size...looks like Moore's law still holds

chipmonk0
User Rank
Author
Re: Memory stacks
chipmonk0   2/11/2014 3:26:57 PM
NO RATINGS
Everyone seems to be backing off from putting a stack of memory chips directly on top of a processor ( per the original JEDEC wide I/O spec ) because of yield, logistics, KGD, thermal -- whatever.

But at least by stacking DRAM chips w/ TSVs they are shrinking the distance btwn individual chips on DIMMs and just about eliminating sync-ing / latency due to chip to chip propagation delay.

both Micron HMC and now HBM ( its a JEDEC std. not just SK Hynix ) put the memory stack off the processor but on the same PCB, or substrate / interposer be it organic / Si. So the resut is either 2-d or 2.5-d with the memory in 3-d, not a pure 3-d

Micron's HMC memory chip stack includes a controller logic chip - all vertically connected by Thru Si Vias (TSVs). The stack sits off the CPU and is connected to it by SerDes.

At least right now, its aimed at the high end, FPGAs, Network Controllers that sort of thing

A certain mass market GPU vendor did n't like this configuration ( not willing to pay for the controller chip )

SK Hynix must have heard that complaint.

So their HBM is just a stack of memory ( w/ the controller chip optional ) all hooked up by TSVs, sits off the CPU / GPU, connected to it by parallel I/O with regular drivers ( as it stands now ) with the bandwidth 20 % slower at 128 GBps.

 



Top Comments of the Week
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Life
Frankenstein's Fix, Teardowns, Sideshows, Design Contests, Reader Content & More
Max Maxfield

March 28 is Arduino Day -- Break Out the Party Hats!
Max Maxfield
6 comments
Well, here's a bit of a conundrum. I just received an email from my chum David Ashton who hails from the "Unfinished Continent" Down Under. David's message was short and sweet; all he said ...

Bernard Cole

A Book For All Reasons
Bernard Cole
1 Comment
Robert Oshana's recent book "Software Engineering for Embedded Systems (Newnes/Elsevier)," written and edited with Mark Kraeling, is a 'book for all reasons.' At almost 1,200 pages, it ...

Martin Rowe

Leonard Nimoy, We'll Miss you
Martin Rowe
5 comments
Like many of you, I was saddened to hear the news of Leonard Nimoy's death. His Star Trek character Mr. Spock was an inspiration to many of us who entered technical fields.

Rich Quinnell

Making the Grade in Industrial Design
Rich Quinnell
16 comments
As every developer knows, there are the paper specifications for a product design, and then there are the real requirements. The paper specs are dry, bland, and rigidly numeric, making ...

Special Video Section
After a four-year absence, Infineon returns to Mobile World ...
A laptop’s 65-watt adapter can be made 6 times smaller and ...
An industry network should have device and data security at ...
The LTC2975 is a four-channel PMBus Power System Manager ...
In this video, a new high speed CMOS output comparator ...
The LT8640 is a 42V, 5A synchronous step-down regulator ...
The LTC2000 high-speed DAC has low noise and excellent ...
How do you protect the load and ensure output continues to ...
General-purpose DACs have applications in instrumentation, ...
Linear Technology demonstrates its latest measurement ...
10:29
Demos from Maxim Integrated at Electronica 2014 show ...
Bosch CEO Stefan Finkbeiner shows off latest combo and ...
STMicroelectronics demoed this simple gesture control ...
Keysight shows you what signals lurk in real-time at 510MHz ...
TE Connectivity's clear-plastic, full-size model car shows ...
Why culture makes Linear Tech a winner.
Recently formed Architects of Modern Power consortium ...
Specially modified Corvette C7 Stingray responds to ex Indy ...
Avago’s ACPL-K30T is the first solid-state driver qualified ...
NXP launches its line of multi-gate, multifunction, ...
Radio
LATEST ARCHIVED BROADCAST
EE Times Senior Technical Editor Martin Rowe will interview EMC engineer Kenneth Wyatt.
Flash Poll