Siwa: A custom RISC-V based system on chip (SOC) for low power medical applications

Abstract This work introduces the development of Siwa, a RISC-V RV32I 32-bit based core, intended as a flexible control platform for highly integrated implantable biomedical applications, and implemented on a commercial 0.18 μm high voltage (HV) CMOS technology. Simulations show that Siwa can outperform commercial micro-controllers commonly used in the medical industry as control units for implantable devices, with energy requirements below the 50 pJ per clock cycle.

[1]  Aaron Stillmaker,et al.  Scaling equations for the accurate prediction of CMOS device performance from 180 nm to 7 nm , 2017, Integr..

[2]  Cynthia A. Chestek,et al.  Enabling Low-Power, Multi-Modal Neural Interfaces Through a Common, Low-Bandwidth Feature Space , 2016, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[3]  Hector Gomez,et al.  A system-on-chip platform for the internet of things featuring a 32-bit RISC-V based microcontroller , 2017, 2017 IEEE 8th Latin American Symposium on Circuits & Systems (LASCAS).

[4]  Wim Dehaene,et al.  A sub 10 pJ/Cycle Over a 2 to 200 MHz Performance Range RISC- V Microprocessor in 28 nm FDSOI , 2018, ESSCIRC 2018 - IEEE 44th European Solid State Circuits Conference (ESSCIRC).

[5]  David Harris,et al.  Integrated circuit design , 2011 .

[6]  Zhihua Wang,et al.  An Energy-Efficient ASIC for Wireless Body Sensor Networks in Medical Applications , 2010, IEEE Transactions on Biomedical Circuits and Systems.

[7]  Luca Benini,et al.  Slow and steady wins the race? A comparison of ultra-low-power RISC-V cores for Internet-of-Things applications , 2017, 2017 27th International Symposium on Power and Timing Modeling, Optimization and Simulation (PATMOS).

[8]  Hassanein H. Amer,et al.  Mitigation of Soft and Hard Errors in FPGA-Based Pacemakers , 2018, 2018 13th International Conference on Computer Engineering and Systems (ICCES).

[9]  Jonathan Rose,et al.  Measuring the Gap Between FPGAs and ASICs , 2006, IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems.

[10]  R. Garcia-Ramirez,et al.  A RISC-V Based Medical Implantable SoC for High Voltage and Current Tissue Stimulus , 2020, 2020 IEEE 11th Latin American Symposium on Circuits & Systems (LASCAS).

[11]  Vaughn Betz,et al.  You Cannot Improve What You Do not Measure , 2018, ACM Trans. Reconfigurable Technol. Syst..

[12]  Luca Benini,et al.  Near-Threshold RISC-V Core With DSP Extensions for Scalable IoT Endpoint Devices , 2016, IEEE Transactions on Very Large Scale Integration (VLSI) Systems.

[13]  Muhammad Waqar,et al.  A Batteryless Sensor ASIC for Implantable Bio-Impedance Applications , 2015, IEEE Transactions on Biomedical Circuits and Systems.

[14]  Luis Rueda,et al.  A 32-bit RISC-V AXI4-lite bus-based microcontroller with 10-bit SAR ADC , 2016, 2016 IEEE 7th Latin American Symposium on Circuits & Systems (LASCAS).

[15]  David Money Harris,et al.  Energy-delay tradeoffs in 32-bit static shifter designs , 2008, 2008 IEEE International Conference on Computer Design.

[16]  David A. Patterson,et al.  An Out-of-Order RISC-V Processor with Resilient Low-Voltage Operation in 28NM CMOS , 2018, 2018 IEEE Symposium on VLSI Circuits.

[17]  Reinaldo Castro-Gonzalez,et al.  RISC-V based sound classifier intended for acoustic surveillance in protected natural environments , 2017, 2017 IEEE 8th Latin American Symposium on Circuits & Systems (LASCAS).

[18]  Zhihua Wang,et al.  A low-power remotely-programmable MCU for implantable medical devices , 2010, 2010 IEEE Asia Pacific Conference on Circuits and Systems.

[19]  Mary Jane Irwin,et al.  Area-time-power tradeoffs in parallel adders , 1996 .

[20]  Andrew Waterman,et al.  The RISC-V Reader: An Open Architecture Atlas , 2017 .

[21]  Guillaume Charvet,et al.  WIMAGINE: Wireless 64-Channel ECoG Recording Implant for Long Term Clinical Applications , 2015, IEEE Transactions on Neural Systems and Rehabilitation Engineering.