Precision Time Interval Generator Based on CMOS Counters and Integration with IoT Timing Systems
Open Access
- 12 August 2025
- journal article
- research article
- Published by MDPI AG in Electronics
- Vol. 14 (16) , 3201
Abstract
Precise time interval generation is a cornerstone of modern measurement, automation, and distributed control systems, particularly within Internet of Things (IoT) architectures. This paper presents the design, implementation, and evaluation of a low-cost and high-precision time interval generator based on Complementary Metal-Oxide Semiconductor (CMOS) logic counters (Integrated Circuit (IC) IC 7493 and IC 4017) and inverter-based crystal oscillators (IC 74LS04). The proposed system enables frequency division from 1 MHz down to 1 Hz through a cascade of binary and Johnson counters, enhanced with digitally controlled multiplexers for output signal selection. Unlike conventional timing systems relying on expensive Field-Programmable Gate Array (FPGA) or Global Navigation Satellite System (GNSS)-based synchronization, this approach offers a robust, locally controlled reference clock suitable for IoT nodes without network access. The hardware is integrated with Arduino and ESP32 microcontrollers via General-Purpose Input/Output (GPIO) level interfacing, supporting real-time timestamping, deterministic task execution, and microsecond-level synchronization. The system was validated through Python-based simulations incorporating Gaussian jitter models, as well as real-time experimental measurements using Arduino’s micros() function. Results demonstrated stable pulse generation with timing deviations consistently below ±3 µs across various frequency modes. A comparative analysis confirms the advantages of this CMOS-based timing solution over Real-Time Clock (RTC), Network Time Protocol (NTP), and Global Positioning System (GPS)-based methods in terms of local autonomy, cost, and integration simplicity. This work provides a practical and scalable time reference architecture for educational, industrial, and distributed applications, establishing a new bridge between classical digital circuit design and modern Internet of Things (IoT) timing requirements.Keywords
This publication has 14 references indexed in Scilit:
- A 500 kHz to 150 MHz Multi-Output Clock Generator Using Analog PLL and Open-Loop Fractional Divider with 0.13 μm CMOSElectronics, 2022
- GateRL: Automated Circuit Design Framework of CMOS Logic Gates Using Reinforcement LearningElectronics, 2021
- High-resolution time-interval generatorPRZEGLĄD ELEKTROTECHNICZNY, 2017
- 5 ps Jitter Programmable Time Interval/Frequency GeneratorMetrology and Measurement Systems, 2017
- Design of time interval generator based on hybrid counting methodNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2016
- Measuring theRCtime constant with ArduinoPhysics Education, 2016
- High-Precision Time Digitizer Based on Multiedge Coding in Independent Coding LinesIEEE Transactions on Instrumentation and Measurement, 2016
- An Eight-Channel 4.5-ps Precision Timestamps-Based Time Interval Counter in FPGA ChipIEEE Transactions on Instrumentation and Measurement, 2016
- Time interval generator with 8 ps resolution and wide range for large TDC array characterizationAnalog Integrated Circuits and Signal Processing, 2015
- Wireless sensor networks: a surveyComputer Networks, 2002