EPWM_总结.doc

DSP2808之EPWM笔记 一、EPWM有什么模式和功能 6个EPWM 包含子模式 This guide describes the Enhanced Pulse Width Modulator (ePWM) Module. It includes an overview of the module and information about each of the sub-modules: ?TB---- Time-Base Module ?CC---- Counter Compare Module ?AQ---- Action Qualifier Module ?DB---- Dead-Band Generator Module ?PC---- PWM Chopper (PC) Module(斩波) ?TZ---- Trip Zone Module ?ET---- Event Trigger Module The ePWM peripheral performs a digital to analog (DAC) function, where the duty cycle is equivalent to a DAC analog value; it is sometimes referred to as a Power DAC. the ePWM is built up from smaller single channel modules with separatere sources and that can operate together as required to form a system 一个完整的PWM通道有两个PWM输出组成：EPWMxA EPWMxB The ePWM modules are chained together via a clock synchronization scheme that allows them to operate as a single system when required. -------(ECAP extended capture peripheral modules 每个EPWM支持功能： 1、专门的带周期和频率控制的16位计数器 2、两路PWM的输出（A,B）可以被配置为 – Two independent PWM outputs with single-edge operation – Two independent PWM outputs with dual-edge symmetric operation One independent PWM output with dual-edge asymmetric operation 双边不对称操作？？ 3、 Asynchronous override control of PWM signals through software. 4、Programmable phase-control support for lag or lead operation relative to other ePWM module 5、Hardware-locked (synchronized) phase relationship on a cycle-by-cycle basis. 6、Dead-band generation with independent rising and falling edge delay control. 7、Programmable trip zone allocation of both cycle-by-cycle trip and one-shot trip on fault conditions. 8、A trip condition can force either high, low, or high-impedance state logic levels at PWM output 9、All events can trigger both CPU interrupts and ADC start of conversion (SOC) 如何理解 10、Programmable event prescaling minimizes CPU overhead on interrupts. 11、PWM chopping by high-frequency carrier signal, useful for pulse transformer gate drives. 通过GPIO外设，死区信号可以被设置成异步输入信号。 Periphera