STT-MRAM FPGA Configuration Memory for Instant Startup
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current FPGAs and CPLAs face issues with high leakage power, volatility of SRAM-based memory, requiring external non-volatile storage, long boot-up times, and security concerns due to off-die configuration data storage.
Innovation Solution
Integration of Spin Transfer Torque Random Access Memory (STTRAM) elements within FPGAs and CPLAs for local, non-volatile storage of configuration data, utilizing 1T1R cells with magnetic tunnel junctions for low power and secure, instant startup capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If SRAM-based memory is used for configuration storage in FPGAs, then fast access speed is achieved, but high leakage power and volatility occur
Solution Approach 1:
The patent changes the physical state and material parameters of the memory cell by replacing conventional SRAM with STT-MRAM technology. This involves changing the storage mechanism from volatile flip-flop latching to non-volatile magnetic moment orientation, fundamentally altering the energy consumption characteristics while maintaining fast access speeds.
Solution Approach 2:
The patent employs a hybrid approach by integrating STT-MRAM memory cells with CMOS logic circuits. This composite structure combines the non-volatile, low-leakage properties of magnetic memory with the high-speed switching capabilities of CMOS, achieving both low power consumption and fast configuration access.
2Speed
If SRAM-based memory is used for configuration storage, then fast access is achieved, but data loss occurs when power is removed
Solution Approach 1:
The patent fundamentally changes the stability parameter by transitioning from volatile SRAM to non-volatile STT-MRAM. The magnetic moment orientation in the tunnel magnetoresistive memory cell provides inherent data retention without power, while the read/write mechanisms maintain compatibility with existing FPGA architectures for fast configuration access.
3Stability of the object's composition
If external non-volatile storage is used for configuration data, then data retention is improved, but device complexity and pin count increase
Solution Approach 1:
The patent merges the configuration storage function directly into the FPGA fabric by integrating STT-MRAM memory cells within the logic array. This eliminates the need for separate external non-volatile storage devices and their associated I/O interfaces, reducing overall device complexity while maintaining non-volatile data retention capabilities.
Solution Approach 2:
The integrated STT-MRAM cells serve multiple functions: they act as both configuration storage and on-chip memory for the FPGA logic elements. This multi-functionality eliminates the need for dedicated external storage interfaces and reduces the overall pin count and system complexity.
4Stability of the object's composition
If external non-volatile storage is used for configuration data, then data retention is improved, but programming time on startup increases
Solution Approach 1:
The patent implements preliminary action by pre-storing configuration data directly in the STT-MRAM memory cells integrated within the FPGA fabric before the device is powered on. Since the configuration data is already present in non-volatile memory on-chip, no time-consuming data transfer from external storage is required during startup, enabling instant activation.
5Quantity of substance
If configuration data is stored in off-die memory arrays, then storage capacity is achieved, but security issues occur
Solution Approach 1:
The patent merges the configuration storage function directly into the FPGA fabric by integrating STT-MRAM memory cells within the logic array. This eliminates the need for separate external non-volatile storage devices and their associated I/O interfaces, reducing overall device complexity while maintaining non-volatile data retention capabilities.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
STTRAM-based FPGAs/CPLAs achieve reduced power consumption, instant startup, and enhanced security by eliminating the need for external storage, reducing costs and pin count while ensuring configuration data remains secure on-die.
Implementation Method 1
Spin Transfer Torque Random Access Memory (STTRAM) is a type of non-volatile RAMs
Data Source
AI summary
Disclosed herein are semiconductor device arrays, such as, Field Programmable Gate Arrays (FPGAs) and Complex Programmable Logic Arrays (CPLAs) that use high-density Spin Transfer Torque (STT)-based memory elements. STT-based memory elements can either be stand-alone FPGAs/CPLAs, or can be embedded in microprocessors and/or digital signal processing (DSP) system-on-chip (SoC) to provide design flexibility for implementing low power, scalable, secure and reconfigurable hardware architecture. Because the configuration is stored on the FPGA/CPLA die itself, the need for loading the configuration from external storage every time is eliminated when the device is powered on. In addition to instant startup, eliminating configuration I/O traffic results in power savings and possible pin count reduction. Security is greatly improved by eliminating the need to store configuration data in an external memory.