Research

Four processor generations. Four open-access papers. FPGA validated on AWS F2 and Kria K26.

N4

Coming soon

Deliver-mode spiking inference engine, validated bit-exact against a golden model on AWS F2 (VU47P) at 62.5 MHz. Scaled to 393,216 neurons on a single FPGA; SHD 90.28% measured on chip across the full test set. Edge variant on Kria K26 at 0.378 W total board power. 28 nm ASIC in design; 130 nm compute tile signed off.

393,216 neurons
Validated bit-exact on FPGA (48 cores × 8,192)
90.28% SHD
Full 2,264-sample test set, measured on chip
Bit-exact
Reproduces a golden model every timestep, zero deployment loss
3 neuron models
LIF, CUBA, adLIF, fixed-point
100–300 mW
ASIC power projection at 28 nm
Zero event loss
Measured across 18M+ routed events
32-context TDM
Multiple networks resident, silicon-validated
62.5 MHz
Validated clock on AWS F2 UltraScale+

N4-Edge

Low-power embedded variant. SRAM-only. Targets $5-20 FPGA modules.

2-core build
Measured on Kria K26
0.378 W
Total board power, Kria K26
2.59% LUT
3,036 of 117,120
+3.301 ns WNS
Positive timing slack
15,668 ts/sec
Sustained throughput on F2

Architecture evolution

Each generation extends the ISA and adds hardware capabilities. N1 through N3 have dedicated product pages with full specifications.

N1 N2 N3 N4
Cores 128 128 128 (16 tiles) 48 (FPGA)
Neurons 131K 131K 524K–1M 393,216 (FPGA)
Neuron models 1 (CUBA LIF) 5 7+ (programmable) 3 (LIF, CUBA, adLIF)
Neuron engine Fixed datapath Microcode Microcode + ANN mode Deliver-mode, bit-exact
Weight precision 8-bit fixed 1–16-bit variable 1–16-bit variable 16-bit fixed
Spike formats Binary Binary + graded Binary + graded + compressed Binary + graded
Learning STDP + reward 3-factor + homeostatic Per-tile Readout adaptation (measured)
Synapse formats 3 4 4 + compression Weighted CSR
Memory 1 level 1 level Multi-level On-die SRAM + DDR model store
Virtualization TDM 32-context TDM
FPGA validated VU47P (16-core) VU47P F2 + K26 F2 + K26
ASIC projection 19–38 mW (28 nm) 100–300 mW (28 nm)

Publications

Second generation 18 pages

Catalyst N2: An Open Neuromorphic Processor with Programmable Neuron Microcode

Programmable neuron microcode, variable-precision weights, 3-factor learning with homeostatic plasticity, graded spike payloads.

DOI 10.5281/zenodo.18728256
First generation 13 pages

Catalyst N1: A 131K-Neuron Open Neuromorphic Processor with Programmable Synaptic Plasticity

128 cores, 131,072 CUBA LIF neurons, STDP + reward-modulated plasticity, 14-opcode learning ISA, SHD 90.6%.

DOI 10.5281/zenodo.18727094

Software

The SDK includes three execution backends. The CPU backend is the reference implementation. Every commit is tested against all three.

CPU
Reference implementation. Deterministic, exact integer arithmetic. Ground truth for all comparisons.
GPU (CUDA)
Parallel backend for training. Statistically equivalent to CPU. Differences limited to floating-point operation reordering.
FPGA
PCIe MMIO driver targeting AWS F2 and Kria K26. Bit-exact spike output match against CPU simulator.
Papers
Open access
Zenodo with DOI
N1 RTL
Apache 2.0
Open source
N2+ RTL
BSL 1.1
Proprietary
SDK
BSL 1.1
Proprietary
API client
MIT
Open source