翻譯 論文 摘要
本文介紹壹種基於AT89C51單片機與MAX262芯片的程控濾波器。MAX262為雙二階開關電容有源濾波器，可通過SPI總線精確控制濾波器的傳遞函數。獨立編程設置其中心頻率和品質因數實現智能控制。AD603是壹種低噪聲的可程控集成運算放在器，通過控制VG即可控制放大增益。單片機的ALE引腳產生的信號經分頻之後可提供給MAX262作為時鐘使用。
該系統設計是由放大器、濾波器、分頻器和控制模塊等部分構成，采用AD603與MAX262相結合,實現增益設置以及滿足高、低濾波參數的要求。
關鍵詞：程控濾波；增益放大；分頻；顯示
Abstract
This article describes a programmable filter based on AT89C51 microcontroller and MAX262 chip. MAX262 is a dual second-order switched capacitor active filter, of which transfer function can be precisely controlled via SPI bus and which can be smartly controlled via independent programming by setting center-frequency and quality factor. AD603 is a low-noise programmable and integrated operational amplifier, with amplification gain regulated by controlling VG. Signals generated on ALE pin of the microcontroller can be provided to MAX262 for clock use.
The system is composed of amplifiers, filters, frequency divider, and control modules, using AD603 and MAX262 combined to realize gain setting and meet the high- and low-filter parameters required.
Keywords: programmable filtering; gain amplification; frequency division; display