Friday, June 22, 2018
Search
  
Submit your own News for
inclusion in our Site.
Click here...
Breaking News
FCC to Seek for Flexible Use of C-band and 6GHz Airwaves
AMD Presents Modular Routing Design for Chiplet-based Systems
Software Business Continues to Work For BlackBerry
Apple Turns to the U.S. Patent Office to Invalidate Qualcomm Patents
Samsung Patents Bezel-less, Notch-free Smartphone Design
China is Home to Most Smartphone Vendors
VidCon 2018: Youtube Announces Memberships, Merchandise as Alternatives to Ads
Chatting With Google Assistant Gets More Natural
Active Discussions
Which of these DVD media are the best, most durable?
How to back up a PS2 DL game
Copy a protected DVD?
roxio issues with xp pro
Help make DVDInfoPro better with dvdinfomantis!!!
menu making
Optiarc AD-7260S review
cdrw trouble
 Home > News > General Computing > Toshiba...
Last 7 Days News : SU MO TU WE TH FR SA All News

Wednesday, February 12, 2014
Toshiba Low Leakage SRAM Enables Fast Wake-up from a Deep Sleep Mode


Toshiba has developed an eXtremely Low Leakage 65nm SRAM (XLL SRAM) suitable for back-up RAM in low power MCU that achieves a fast wake-up time from a deep sleep mode.

Presented at the 2014 IEEE International Solid-State Circuits Conference in San Francisco, California, on February 11, the new SRAM can retain data for over 10 years with a single battery charge.

There is strong demand for long battery discharge times in low power systems, including wearable devices, healthcare tools and smart meter. Although there are many challenges to reduce power of MCU used in these systems, with advances in the process generation, increasing of leakage current becomes problem as well as active power consumption. Reducing leakage current in RAM, which retains data during stand-by, is particularly important.

A typical MCU reduces power dissipation with a deep sleep mode, where stand-by current is under 1µA. However, this makes it impossible for typical SRAM to retain data, as SRAM require a stand-by current much higher than 1?A. As a result, data reloading takes a long time when the system wakes up from a deep-sleep mode. Use of FRAM as back-up RAM eliminates this reload problem, but FRAM is much slower and consumes more active power than SRAM and also needs more process cost.

Toshiba has developed an eXtremely Low Leakage SRAM (XLL SRAM) that has a leakage rate a thousand times lower than that of conventional SRAM; 27fA leakage current per bit when fabricated in 65nm process. This level is lower than that found in published data for SRAM beyond 65nm technology. The new SRAM can retain data for over 10 years with a single battery charge, in a back-up memory with a capacity of around 100Kbyte.

MOSFET fabricated with recent process technology has higher gate leakage, gate induced drain leakage (GIDL) and channel leakage. Toshiba has developed a low leakage transistor with thick gate oxide, long channel length and optimum source drain diffusion profile to reduce these leakage factors, and adopt it in the SRAM memory cell. The company has developed several leakage reduction circuits. One is a source bias circuit to apply reverse back-bias to NMOS of memory cell, and another cuts off the supply voltage to peripheral circuits during data retention.

The low leakage transistor is larger than conventional transistor, increasing the overall cell area. Toshiba secured a 20% reduction in cell size compared to area designed by original design rule of this device under the condition of 1.2V supply voltage. Generally, large transistor circuits have higher active power dissipation. Toshiba has suppressed this by adopting "Quarter Array Activation Scheme (QAAS)" and "Charge Shared Hierarchical BitLine (CSHBL)" power reduction circuits.

An SRAM with a 7ns read access time is fast enough to be used as working RAM in low power MCU and for use as back-up RAM in deep-sleep mode because of its extremely low leakage current. As the system eliminates data reloading, the wake-up time from deep sleep mode is boosted.

Toshiba plans to use the SRAM in a product released in 2014, and expects to see wide use in coming battery-driven products.




Previous
Next
LG Confirms LG G2 Mini Coming        All News        Samsung to Unveil New Bent Smartphones This Year
Samsung Joins IBM In OpenPower Alliance     General Computing News      Firefox To Show Ads On New Tab Page Tiles

Get RSS feed Easy Print E-Mail this Message

Related News
Toshiba Delivers RM5 vSAS Series SSDs Targeting SATA Applications
Value-Optimized Toshiba RC100 NVMe SSDs Now Available
Sharp to buy Toshiba's PC Business
Sharp close to Buying Toshiba's PC Business
Bain Capital to Support Toshiba Memory's Future Acquisitions
Toshiba Completes $18bn Sale of Flash Memory Unit
Toshiba Introduces New XS700 Series of Portable SSDs
Toshiba's Twin-Field Quantum Key Distribution Extends the Limit of Intercity Secure Communications
Toshiba Confirms Approval of $18 billion Chip Unit Sale by China
China Finally Approves Toshiba's Plan to Sell Its Memory Chip Unit: report
Toshiba Weighs Memory Chip Unit Options
Toshiba Releases New Surveillance, Video Streaming Laptop and Desktop Hard Drives

Most Popular News
 
Home | News | All News | Reviews | Articles | Guides | Download | Expert Area | Forum | Site Info
Site best viewed at 1024x768+ - CDRINFO.COM 1998-2018 - All rights reserved -
Privacy policy - Contact Us .