基于MSP430和MAX262程控滤波器的设计  

Design of programmable filter based on MSP430 and MAX262

作　　者：何明[1] 乔龙飞[1] 许朋[1] 

机构地区：[1]武汉大学电子信息学院,湖北武汉430079

出　　处：《电子设计工程》2011年第4期179-181,共3页Electronic Design Engineering

摘　　要：随着手持设备的广泛应用,为了满足系统设备的低功耗要求,设计了基于单片机MSP430、数字频率源LTC6903、开关电容滤波芯片MAX262的低功耗程控滤波器。系统采用单片机控制数字频率源芯片LTC6903提供步进可调的时钟信号,以实现对滤波器截止频率的灵活调节和滤波类型的转换。该系统改善了传统有源滤波器器件参数设计困难,截止频率等参数难以灵活控制和调节的问题。与传统有源滤波器相比,可以完成低通、高通、带通、陷波功能的转换,滤波器Q值范围0.5～8程控调节,截止频率在100 Hz～40 kHz之间100 Hz步进可调。此外,系统在3.3 V的供电条件以及单片机的ShutDown模式下,比一般的程控滤波器具有更低的功耗。With the widely application of portable devices, in order to meet the low power consumption demand of systems equipment, a low-power programmable filter was designed based on microcontroller MSP430, digital frequency source chip LTC6903 and programmable switched capacitor filter chip MAX262. This system used digital frequency source chip LTC6903 to provide an adjustable clock, which realized the flexible adjustment of filter cutoff frequency and filter types. The system had overcome the parameter design problems of traditional active filters, and the problem of that flexible cut-off frequency and other parameters are difficult to control. Compared with the traditional active filter, it also has functional shift of low pass, high pass, band pass and trap. Q value of the filter is programmable from 0.5 to 8, and cutoff frequency is adjustable from 100Hz- 40kHz. In addition, with the 3.3V power supply condition and the MCU ShutDown mode, this system has lower power consumption than the common one.

关 键 词：可编程 开关电容滤波器 单片机 幅频特性测试 

分 类 号：TN713[电子电信—电路与系统]