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Edward Choi

Korea Advanced Institute of Science and Technology · Engineering

About the Lab

Professor Edward Choi's research lab specializes in energy-efficient computing architectures for machine learning workloads, with a focus on compute-in-memory (CIM) systems using SRAM and embedded non-volatile memory (eNVM). The lab develops mixed-signal and digital-in-memory computing techniques to enable high-throughput, low-energy inference of deep neural networks (DNNs) in edge devices. Key innovations include charge-domain computation, hybrid digital-phase domain processing, and novel data formats like two’s-complement with skewing to mitigate analog nonidealities and process variations. The lab also pioneers on-chip neural processing for neuromorphic applications, such as spike sorting using analog CIM-based autoencoders.

compute-in-memoryenergy efficiencyneural network inferenceSRAM-based CIManalog mixed-signal computing

Research Overview

Papers
18
Total Citations
78
Papers (5y)
18
Primary Field
Engineering

Research Output Trend

Figures are computed from collected data and may differ slightly.

Publications per year (5y)
18total
2022
2023
2024
2025
2026
Citations per year (5y)
78total
20222023202420252026

Selected Papers

15
1
Article|25 citations·2022
SRAM-Based Computing-in-Memory Macro With Fully Parallel One-Step Multibit Computation
Edward Choi, Injun Choi, Chanhee Jeon, Gichan Yun, Donghyeon Yi, Sohmyung Ha, Ik‐Joon Chang, Minkyu Je
SJR Q1IEEE Solid-State Circuits Letters

In this letter, we present a multi-bit SRAM computing-in-memory (CIM) macro with enhanced energy efficiency for edge devices tasking machine learning (ML) deep neural networks (DNN). The proposed CIM macro computes matrix-vector multiplications (MVM) in an efficient “one-step" method reducing the energy consumption and control complexity. Furthermore, the proposed method computes not only the multiplications of a single weight but also the multi-bit weight with bit-shifting in the charge domain

Electrical and Electronic EngineeringEngineering
2
Article|21 citations·2022
A 133.6TOPS/W Compute-In-Memory SRAM Macro with Fully Parallel One-Step Multi-Bit Computation
Edward Choi, Injun Choi, Chanhee Jeon, Gichan Yun, Donghyeon Yi, Sohmyung Ha, Ik‐Joon Chang, Minkyu Je
2022 IEEE Custom Integrated Circuits Conference (CICC)

Over the years, SRAM-based compute-in-memory (CIM) structures have shown ways to perform deep neural network (DNN) computations in the mixed-signal domain with high energy efficiency but suffer from the tradeoff and limitations in their accuracy arising from analog nonidealities. Recently, circuit techniques were developed to support multi-bit analog computations in SRAM-based CIM macro [1], [2], which computes multiplication and accumulation by using transistor currents. However, the transistor

Electrical and Electronic EngineeringEngineering
3
Article|10 citations·2023
A 333TOPS/W Logic-Compatible Multi-Level Embedded Flash Compute-In-Memory Macro with Dual-Slope Computation
Edward Choi, Injun Choi, Vincent Lukito, Dong-Hwi Choi, Donghyeon Yi, Ik‐Joon Chang, Sohmyung Ha, Minkyu Je

Computing-in-memory (CIM) has been an ongoing prominent research area for easing the energy efficiency of machine learning tasks in edge devices. Recently, embedded non-volatile memory (eNVM) CIM architectures have been popular as an edge device, where it can turn off their supply during standby for low power consumption. However, most eNVMs (e.g., MRAMs and RRAMs) require the use of specialized technologies and are mostly used as single-level cell (SLC) data storage [2], [3]. In the technologie

Electrical and Electronic EngineeringEngineering
4
Article|9 citations·2022
An SRAM-Based Hybrid Computation-in-Memory Macro Using Current-Reused Differential CCO
Injun Choi, Edward Choi, Donghyeon Yi, Yoontae Jung, Hoyong Seong, Hyuntak Jeon, Soon-Jae Kweon, Ik‐Joon Chang, Sohmyung Ha, Minkyu Je
SJR Q1IEEE Journal on Emerging and Selected Topics in Circuits and Systems

This work presents a 4 kb 8T-SRAM computation-in-memory (CIM) macro based on hybrid computation using digital in-memory-array computing (DIMAC) and phase-domain near-memory-array computing (PNMAC). By employing multiple local dual-column arrays (LDCAs), bit-wise multiplications are computed digitally in memory with high energy efficiency and throughput. The PNMAC performs the summation and accumulation in parallel with a high dynamic range by using a proposed steering-DAC-based differential curr

Electrical and Electronic EngineeringEngineering
5
Article|5 citations·2024
Skew-CIM: Process-Variation-Resilient and Energy-Efficient Computation-in-Memory Design Technique With Skewed Weights
Donghyeon Yi, Seoyoung Lee, Injun Choi, Gichan Yun, Edward Choi, Jong-Hee Park, Jonghoon Kwak, Sung‐Joon Jang, Sohmyung Ha, Ik‐Joon Chang, Minkyu Je
SJR Q1IEEE Transactions on Circuits and Systems I Regular Papers

In analog-mixed-signal (AMS) compute-in-memory (CIM) systems, the two’s-complement (2SC) format provides better area efficiency than the sign-and-magnitude (SNM) one. However, the 2SC format exacerbates the challenges of AMS-CIM systems, suffering from significant DNN accuracy drop under process variations and high computation currents from activating multiple WLs. In the 2SC format, ‘0’ and ‘1’ are nearly balanced for all logical-order bits, unlike ‘0’-skewed higher-order bits in the SNM format

Electrical and Electronic EngineeringEngineering
6
Article|2 citations·2024
A -Based Spike Sorting SoC with End-to-End Implementation of Event-Driven Binary Autoencoder Neural Network in Analog CIM Achieving 94.54% Accuracy and 3.11W/ch
Edward Choi, Vincent Lukito, Injun Choi, Seoyoung Lee, Ik‐Joon Chang, Sohmyung Ha, Minkyu Je

The proposed <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta$</tex>-based spike sorting (SS) SoC is the first on-chip implementation of an analog computing-in-memory (CIM) binary autoencoder neural network (B-AENN) feature extraction with enhanced spike detection adopting <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta$</tex>-spikes, resulting in the highest on-chip SS classification acc

Hardware and ArchitectureComputer Science
7
Article|2 citations·2024
AR-CIM: A 460.22TOPS/W SRAM-based Analog Reconfigurable Computing-in-Memory Macro with 1/2/4/8-Bit Variable Precision
Bo‐Ran Choi, Edward Choi, Donghyeon Yi, Jiho Chun, Sohmyung Ha, Ik‐Joon Chang, Minkyu Je

This work presents an SRAM-based analog reconfigurable computing-in-memory macro with 409.6-GOPS throughput and 460.22-TOPS/W energy efficiency. The proposed reconfigurable macro supports $1 / 2 / 4 / 8 \mathrm{~b}$ inputs and $1 / 2 / 4 / 8 \mathrm{~b}$ signed weights while maintaining 100% memory utilization. Furthermore, we propose (i) a dual-domain DAC to achieve high-precision input with low area overhead and (ii) an input-sense-and-skip SAR ADC, which reduces the average power overhead by

Electrical and Electronic EngineeringEngineering
8
Article|1 citations·2026
Opioid Use as a Predictor of Pancreas Transplant Outcomes
Youngmin Ko, Eunbyeol Cho, Hye Eun Kwon, Hye Eun Kwon, Jin‐Myung Kim, S SHIN, Young Hoon Kim, Edward Choi, ByungHyun Choi, Hyunwook Kwon, Hyunwook Kwon
SJR Q2Clinical Transplantation

BACKGROUND: Posttransplant opioid dependence has been linked to adverse outcomes in solid organ transplantation, but its impact on pancreas transplantation is underexplored. METHODS: This retrospective study analyzed 193 PTA/PAK recipients from Asan Medical Center (AMC) (2010-2022) and externally validated results in 77 recipients from Pusan National University Yangsan Hospital (PNUYH) (2015-2022). Posttransplant opioid dependence was defined as ≥ 10 opioid prescriptions between 3 and 12 months

SurgeryMedicine
9
Article|1 citations·2026
Large Language Model–Generated Expansion of the RadLex Ontology: Application to Multinational Datasets of Chest CT Reports
Taehee Lee, Hyungjin Kim, Seowoo Lee, Seonhye Chae, Charles E. Kahn, Seng Chan You, Edward Choi, Soon Ho Yoon
SJR Q1American Journal of Roentgenology

The LLM-based approach provides a practical and scalable solution for expanding radiology ontologies while maintaining semantic alignment; the method can aid real-world natural language processing applications.

Molecular BiologyBiochemistry, Genetics and Molecular Biology
10
Article|1 citations·2025
A No-Patient-Data Seizure Classifier Soc for Real-Time Classification of Seven Seizure Types Using Feature Fusion and Near-Memory Computing
Vincent Lukito, Edward Choi, Seoyoung Lee, Jimin Koo, Ik‐Joon Chang, Sohmyung Ha, Minkyu Je

The proposed multi-seizure-type classifier (MSTC) SoC is the first on-chip classification of multiple seizure types, integrating frequency-based feature fusion (FF) and digital ternary near memory computing (NMC) to achieve a classification accuracy of 91.63 % with <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$24.72 \mu ~\mathrm{s}$</tex> computational latency. The MSTC SoC is also the first true zero-shot seizure detection system requiring no pa

Cognitive NeuroscienceNeuroscience
11
Article|1 citations·2023
Exploration Into Translation-Equivariant Image Quantization
Woncheol Shin, Gyubok Lee, Jiyoung Lee, Eunyi Lyou, Joonseok Lee, Edward Choi

This is an exploratory study that discovers the current image quantization (vector quantization) do not satisfy translation equivariance in the quantized space due to aliasing. Instead of focusing on anti-aliasing, we propose a simple yet effective way to achieve translation-equivariant image quantization by enforcing orthogonality among the codebook embeddings. To explore the advantages of translation-equivariant image quantization, we conduct three proof-of-concept experiments with a carefully

Computer Vision and Pattern RecognitionComputer Science
12
Article|0 citations·2024
An SRAM-based Error-Free Time Domain Pulse Train Computing-In-Memory Macro achieving 226.14 TOPS/W and 5.782 TOPS/mm2
Edward Choi, Jiho Chun, Bo‐Ran Choi, Sohmyung Ha, Ik‐Joon Chang, Minkyu Je

This paper presents an SRAM-based input bit configurable pulse-train computing-in-memory (CIM) macro for edge devices. The proposed macro computes matrix-vector-multiplications (MVM) in a bit-wise manner, generating pulse trains to overcome the limited signal margin and variations occurring in analog time-domain SRAM-based CIM macros. Furthermore, the system architecture comprises an error-free dynamic OR gate discharge computation, effectively addressing the non-linearity associated with analog

Electrical and Electronic EngineeringEngineering
13
erratum|0 citations·2022
Erratum to “SRAM-Based Computing-in-Memory Macro With Fully Parallel One-Step Multibit Computation”
Edward Choi, Injun Choi, Chanhee Jeon, Gichan Yun, Donghyeon Yi, Sohmyung Ha, Ik‐Joon Chang, Minkyu Je
SJR Q1IEEE Solid-State Circuits LettersOA

In the above article <xref ref-type="bibr" rid="ref1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[1]</xref> , <xref ref-type="fig" rid="fig1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Fig. 6</xref> was placed twice, once as <xref ref-type="fig" rid="fig1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Fig. 6</xref> and again as <xref ref-type="fig" rid="fig2"

Electrical and Electronic EngineeringEngineering
14
dataset|0 citations·2025
Lunguage: A Benchmark for Structured and Sequential Chest X-ray Interpretation
Jong Hak Moon, Geon Y. Choi, Paloma Rabaey, Min Gwam Kim, Hyuk Gi Hong, Jung Oh Lee, Hangyul Yoon, Eunwoo Doe, Jiyoun Kim, Harshita Sharma, Daniel Coelho de Castro, Javier Alvarez Valle
PhysioNetOA

Radiology reports convey detailed clinical observations and capture diagnostic reasoning that evolves over time. However, existing evaluation methods are limited to single-report settings and rely on coarse metrics that fail to capture fine-grained clinical semantics and temporal dependencies. We introduce **LUNGUAGE** , a benchmark dataset of structured radiology reports that serves as a gold standard for evaluating structured report frameworks. It is designed to support comprehensive assessmen

15
Article|0 citations·2025
A Spike Sorting SoC With Δ-Based Spike Detection and End-to-End Implementation of Autoencoder Feature Extraction Using Analog CIM
Vincent Lukito, Edward Choi, Ik‐Joon Chang, Sohmyung Ha, Minkyu Je
SJR Q1IEEE Journal of Solid-State Circuits

To process the substantial data generated from on-chip neural recordings, a robust spike sorting (SS) system-on-chip (SoC) with minimal latency is essential to ensure timely response in closed-loop brain–computer interface (BCI) applications. In this article, we report a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta $</tex-math> </inline-formula>-based SS SoC featuring the first on-chip incorporation

Industrial and Manufacturing EngineeringEngineering

Research Areas

Electrical and Electronic EngineeringSurgeryHardware and ArchitectureMolecular BiologyCognitive NeuroscienceComputer Vision and Pattern Recognition

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