使用PWM生成模拟输出

Pulse Width Modulation (PWM) modules, which pro-duce basically digital waveforms, can be used as cheap
Digital-to-Analog (D/A) converters only a few external
components. A wide variety of microcontroller
applications exist that need analog output but do not
require high resolution D/A converters. Some speech
applications (talk back units, speech synthesis systems
in toys, etc.) also do not require high resolution D/A
converters. For these applications, Pulse Width
Modulated outputs may be converted to
analog outputs.
AN538
Using PWM to Generate Analog Output
FIGURE 2: FREQUENCY SPECTRUM OF A
Author: Amar Palacherla PWM SIGNAL
Microchip Technology Inc.
Fundamental
component Harmonics
Pulse Width Modulation (PWM) modules, which pro-
duce basically digital waveforms, can be used as cheap Frequency
spectrum o