English

VitaLLM: A Versatile and Tiny Accelerator for Mixed-Precision LLM Inference on Edge Devices

Hardware Architecture 2026-05-04 v1

Abstract

We present VitaLLM, a mixed precision accelerator that enables ternary weight large language models to run efficiently on edge devices. The design combines two compute cores, a multiplier free TINT core for ternary-INT projections and a BoothFlex core that reuses a radix-4 Booth datapath for both INT8×\timesINT8 attention and ternary-INT-sustaining utilization without duplicating arrays. A predictive sparse attention mechanism employs a leading-one (LO) surrogate with a comparison-free top-KK selector to prune key/value (KV) fetches by roughly 1K/M1-K/M for MM cached tokens, confining exact attention to KK candidates. System-level integration uses head-level pipelining and an absmax-based quantization barrier to standardize cross-core interfaces and overlap nonlinear reductions with linear tiles. A 16 nm silicon prototype at 1 GHz/0.8 V achieves 72.46 tokens/s in decode and 0.88 s prefill (64 tokens) within 0.214 mm^2 and 120 KB on-chip memory, while reducing KV traffic and improving utilization in ablations. These results demonstrate practical BitNet b1.58 (3B) inference on edge-class platforms and provide a compact blueprint for future mixed-precision LLM accelerators.

Keywords

Cite

@article{arxiv.2605.00320,
  title  = {VitaLLM: A Versatile and Tiny Accelerator for Mixed-Precision LLM Inference on Edge Devices},
  author = {Zi-Wei Lin and Tian-Sheuan Chang},
  journal= {arXiv preprint arXiv:2605.00320},
  year   = {2026}
}

Comments

accepted in ISCAS 2026

R2 v1 2026-07-01T12:44:39.286Z