98 IEEE cIrcuIts and systEms magazInE sEcOnd quartEr 2018 Iadn (a) Σ Iin Vim Iout + Σ Vim I ∈ [-VR, VR] Iout = f (Iin) Analogue Processing Circuitry + Vim ∈ [Vmin, Vmax] + Vzero Vim (b) Dim = 0 ⇒ Vim = Vmin Dim = 1 ⇒ Vim = Vmax Binary to Analogue Conversion Vim ≤ Vzero ⇒ Dim = 0 Vim > Vzero ⇒ Dim = 1 Analogue to Binary Conversion Active Pixel I/O LDMs HitAndMiss LLU Local Analogue Memories Vim Vzero - Image Q-Eye Interface Image I/O Binary-to-Analog Conversion Analog-to-Binary Conversion Image Shifter Figure 6. (a) concept of vision sensor with cVIs front-end; (b) architecture of a q-Eyetm cell [19], [20], [27]. MAC LAMs Resistive Grid Optical Sensor Global References Iddn Dim Dim Dout Dim ∈ {0, 1} Dout = g (Din) Digital Processing Circuitry Din Dim ∈ {0, 1} Local Digital Memories