Industrial MCU oriented transcendental function unit design

doi:10.7523/j.ucas.2023.009

Abstract

Abstract: The calculation of transcendental functions is one of the necessary steps in industrial control algorithms. As the complexity of industrial control systems increases, calculating the transcendental function by software approximation algorithm takes up a large number of CPU cycles, compressing the computational resources of real-time control algorithms and reducing the accuracy of closed-loop control. Equipped with hardware accelerating units, industrial microcontroller unit architecture becomes the preferred solution to solve this contradiction. In this paper, a multi-threaded, high-performance, configurable transcendental function unit based on digital iterative algorithms was designed, which supports trigonometric function, exponential, and logarithmic calculations. The design was synthesized by standard cell library of SMIC 40 nm eFlash platform, resulting in a clock frequency of 200 MHz and an area of 301 074 μm².

Key words: transcendental function, accelerator, control algorithms, digital iterative algorithms, CORDIC

CLC Number:

TN492

SONG Minte, LIU Nan, RU Zhanqiang, YIN Zhizhen, DING Peng, WANG Zhengguang, CHENG Suzhen, SONG Helun. Industrial MCU oriented transcendental function unit design[J]. Journal of University of Chinese Academy of Sciences, 2025, 42(2): 260-267.

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