中圖分類號(hào)： TN713
文獻(xiàn)標(biāo)識(shí)碼： A
DOI：10.16157/j.issn.0258-7998.212420
中文引用格式： 楊春玲，張揚(yáng)，楊旭強(qiáng)，等. 程控開(kāi)關(guān)電容低通濾波器的通用模塊開(kāi)發(fā)[J].電子技術(shù)應(yīng)用，2022，48(9)：136-139.
英文引用格式： Yang Chunling, Zhang Yang，Yang Xuqiang，et al. Development of general module for program-controlled switching capacitor low pass filter[J]. Application of Electronic Technique，2022，48(9)：136-139.

Development of general module for program-controlled switching capacitor low pass filter

Abstract： In the process of electronic noise measurement and harmonic distortion measurement, the filter is used to acquire the signal of specific frequency band or suppress the noise. In this paper, a programmable switching capacitor low-pass filter module with adjustable bandwidth is developed, and the clock signal with adjustable frequency output by STM32 MCU is used to control the cut-off frequency of the filter, which improves the situation that the existing filter cannot adjust the dynamic frequency range due to the fixed parameters. The experimental results show that the passband of the programmable filter can be adjusted at 10 Hz～40 kHz, and it has an obvious ability to suppress the out-of-band signals, which meets the design requirements.

Key words : switched capacitor filter; program-controlled filter; STM32