March 24, 2011 -- The need to provide more functionality at lower cost in small portable devices is driving the demand for more processors on a single chip. Market research firm In-Stat cites MCUs, DSPs, applications processors, and baseband processors among those now being integrated. This trend is creating new demand for embedded anti-fuse, one-time programmable (OTP) non-volatile memory (NVM) intellectual property (IP). NVM OTP IP is becoming desirable to contain microcode storage such as boot loaders, protocol stacks, embedded control programs and data storage such as encryption keys, personal identification numbers (PINs), and event recording (time stamps, counter values, sensor data, etc.).
One application for embedded NVM OTP is to contain boot code, which can range in size from 8kBytes to 512kBytes for applications processors. NVM OTP is particularly attractive in this instance because of the added security it provides. The memory is impervious to conventional means of reverse engineering: de-processing and scanning electron microscope, providing a much superior protection compared to any metal/via ROM or fuse or poly fuse technology.
Bringing the boot code on-chip as opposed to storing it off-chip and loading it into embedded SRAM on initialization has the added benefit of reducing total bill-of-material cost by eliminating an unnecessary chip and saving on the order of $0.10. If the code is currently stored in embedded flash or EPROM, using NVM OTP instead eliminates the added mask layers these embedded devices add to the total chip manufacturing cost.
For baseband processors handling Bluetooth, 802.11, FM, CDMA, GSM, among others depending on geography, NVM OTP is providing protocol stack storage for each of these communications standards. The memory is also desirable for fixing problems that show up in final silicon. For example, if the design team determines that the Bluetooth radio is interfering with the 802.11 radio after tape-out, instead of a design re-spin, the problem might be solved by fixes to the microcode in NVM OTP memory. Using the Kilopass latest 4-MByte Gusto offering, for example, chip designers can accommodate several microcode fixes over the life of the product.
One application where NVM OTP is proving particularly useful is in compliance testing. When a bug is encountered during compliance testing and the device has burned-in ROM, the chip must be fixed and the compliance test repeated, resulting in a time-to-market delay of several months. With NVM OTP, the bug is patched and the compliance test resumes without any delay.
The other compelling force driving increased adoption of NVM OTP is process technology evolution. Kilopass NVM OTP is manufactured in a standard CMOS process making it available on each new process generation as soon as the process is ready for commercial production. Kilopass NVM OTP scales with advanced process nodes resulting in increased capacities for a given die area with each new process generation. This provides larger cost-effective on-chip storage and facilitates new applications.
By Edward Cheng.
Edward Cheng is the Field Marketing and Applications Manager at Kilopass, Inc.. Prior to Kilopass, Edward was the Sr. Staff Applications Engineer at Telegent Systems, supporting customers and teams on areas of software integration, RF hardware design, and system bring-up and debug.
Go to the Kilopass Technology, Inc. website to learn more.