A 0.5-V Linear Neuromorphic Voltage-to-Spike Encoder Using a Bulk-Driven Transconductor
2026-04-10 • Hardware Architecture
Hardware ArchitectureNeural and Evolutionary Computing
AI summaryⓘ
The authors designed a tiny, energy-efficient electronic circuit that converts a voltage input into a series of spikes with a nearly straight-line relationship. They combined special transistor arrangements to keep the voltage-to-current conversion very accurate and stable. Their circuit works at very low power and small size, making it useful for devices that need to quickly translate signals into spikes without using much energy.
voltage-to-spike encoderbulk-driven transconductorDPI neuronLIF neuronlinearizationTSMC 0.18-um CMOScurrent-to-spike conversionultralow powerfiring rateanalog circuit design
Authors
Meysam Akbari, Erika Covi, Kea-Tiong Tang
Abstract
This work introduces an ultralow-power voltage-to-spike encoder that achieves near-linear voltage-to-firing-rate conversion by pairing a linearized bulk-driven transconductor with a DPI-based LIF neuron. A tail-less bulk-driven differential pair improves large-signal linearity, while a translinear linearization network suppresses the dominant sinh nonlinearity and stabilizes the bias-tunable V-to-I gain. The resulting current feeds a DPI front-end that linearizes current-to-spike conversion. Fabricated in TSMC 0.18-um CMOS and operating at VDD = 0.5 V with 2-27 nA reference current, the encoder achieves a deviation of less than 5.6 percent from linearity over 0.1-0.4 V input, consumes 22-180 nW, and occupies 0.0074 mm^2.