In this paper, we propose MRIMA, as a novel MRAM-based In-Memory Accelerator for non-volatile, flexible, and efficient in-memory computing. MRIMA transforms current Spin Transfer Torque Magnetic Random Access Memory (STT-MRAM) arrays to massively parallel computational units capable of working as both non-volatile memory and in-memory logic. Instead of integrating complex logic units in cost-sensitive memory, MRIMA exploits hardware-friendly bit-line computing methods to implement complete Boolean logic functions between operands within a memory array in a single clock cycle, overcoming the multi-cycle logic issue in contemporary Processing-In-Memory (PIM) platforms. We present practical case studies to demonstrate MRIMA’s acceleration for binary-weight and low bit-width Convolutional Neural Networks (CNN) as well as data encryption. Our device-to-architecture co-simulation results on CNN acceleration demonstrate that MRIMA can obtain 1.7× better energy-efficiency and 11.2× speed-up compared to ASICs, and, 1.8× better energy-efficiency and 2.4× speed-up over the best DRAM-based PIM solutions. As an AES in-memory encryption engine, MRIMA shows 77% and 21% lower energy consumption compared to CMOS-ASIC and recent domain wall-based design, respectively.
PIMA-logic: a novel processing-in-memory architecture for highly flexible and energy-efficient logic computation
In this paper, we propose PIMA-Logic, as a novel Processing-in-Memory Architecture for highly flexible and efficient Logic computation. Insteadof integrating complex logic units in cost-sensitive memory, PIMA-Logic exploits a hardware-friendly approach to implement Boolean logic functions between operands either located in the same row or the same column within entire memory arrays. Furthermore, it can efficiently process more complex logic functions between multiple operands to further reduce the latency and power-hungry data movement. The proposed architecture is developed based on Spin Orbit Torque Magnetic Random Access Memory (SOT-MRAM) array and it can simultaneously work as a non-volatile memory and a reconfigurable in-memory logic. The device-to-architecture co-simulation results show that PIMA-Logic can achieve up to 56% and 31.6% improvements with respect to overall energy and delay on combinational logic benchmarks compared to recent Pinatubo architecture. We further implement an in-memory data encryption engine based on PIMA-Logic as a case study. With AES application, it shows 77.2% and 21% lower energy consumption compared to CMOS-ASIC and recent RIMPA implementation, respectively.
- Award ID(s):
- Publication Date:
- NSF-PAR ID:
- Journal Name:
- 55th Annual Design Automation Conference
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- 1 to 6
- Sponsoring Org:
- National Science Foundation
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