4 Replies Latest reply on Dec 26, 2018 11:49 PM by user_3938561

    Questions on configuration of IDAC

    user_3938561

      Hi everyone:

      I'm using PSoC 42 BLE kit to develop a controllable current source output. some questions on IDAC component remains unclear:

       

      1. is there any method to control the polarity of IDAC(current sink or source), for  example: software method using some functions, (p.s. I know PSoC 5LP can do that, but seems that in PSoC 42 hasn't got such functions)

      2. as I know, the current source will usually have two output pins, as the graph shown below, however the output of the IDAC just has one pin, so is the another pin should be connected to the GND?

       

      Appreciation for the help...

      Current_source_symbol(vector_graphics).png捕获.PNG

        • 1. Re: Questions on configuration of IDAC
          RuzheZ_36

          王工:

           

          1. 可以使用firmware在代码运行过程中控制极性。在[IDAC_INSTANCE_NAME]_Init()的函数中有关于配置sink还是source的寄存器操作;

          2. 只需要一个管脚,不需要另一个管脚接地。

           

          Thanks,

          Ryan

          1 of 1 people found this helpful
          • 2. Re: Questions on configuration of IDAC
            user_3938561

            Ryan 您好:

            很高兴收到您的回复,除此以外还有一些小问题想请教您,

            关于您第一个问题的回复,我想知道如何去访问寄存器操作,由于我现在刚刚接触Cypress PSoC系列的MCU,所以我对每一个组件的了解仅限于读相应的datasheet, 但inital函数的定义在datasheet中是这么给出的:

            意思大概是这个函数就是代表我在IDAC组件中设置的参数,我的设计的要求是使用某些数字信号的高低电平来控制IDAC输出拉电流和灌电流,在PSoC 5LP中的IDAC可以做到这一点由于其极性是可控的,如下图:

            tempsnip.png

            这个选项在42BLE的iDAC中没有显示,可能与各个型号的板子的IDAC的版本有关吧

             

            第二个问题上,IDAC输出的电流是单路的,如果我要用输出作为电流源去驱动负载,负载的一端接Iout,请问那另一端该如何连接是正确的呢?

             

            期待您的回复

             

            WH

            • 3. Re: Questions on configuration of IDAC
              RuzheZ_36

              Hi WH,

               

              第一个问题,是的,主要是和各个型号的芯片、组件的版本有关。

              第二个问题,另外一端根据是sink还是source做上拉或者接地。

               

              Thanks,

              Ryan

              1 of 1 people found this helpful
              • 4. Re: Questions on configuration of IDAC
                user_3938561

                感谢您的解答