3 Replies Latest reply on Mar 26, 2018 7:21 AM by e.pratt_1639216

    PSoC4000Sの「TSTARTUP」のMAX値を教えてください

    user_516405692

      PSoC5のデータシートには、パワーオンリセットから、リセットベクタのコードを実行するまでの時間「TSTARTUP」が規定されています。

      PSoC4000Sのデータシートには「TSTARTUP」の規定がありません。(PSoC4全般に内容です。)

      PSoC4000Sの「TSTARTUP」の値を教えてください。

       

      ※PSoC4の起動時の動作は、AN60616とAN73854を参照した結果、

      PSoC5などと同様だと理解しています。

        • 1. Re: PSoC4000Sの「TSTARTUP」のMAX値を教えてください
          e.pratt_1639216

          I would assume the T startup time is different from the clock startup times. But I did find that the IMO startup is 7 us and the ILO startup time is 2 ms. But otherwise, sorry I can't help out more

          Datasheet if you need it: http://www.cypress.com/file/139976/download

          • 2. Re: PSoC4000Sの「TSTARTUP」のMAX値を教えてください
            user_516405692

            Thank you for your response.

            Could you teach me for more details?

             

            "TSTARTUP" of PSoC 5 is "Hardware Startup" time.

            According to Figure 1 of AN 60616, it is the total time of Rest and Boot.

             

            Please teach me about TSTARTIMO and TSTARTILO 1 of PSoC 4.

            "Hardware Startup" time when starting PSoC 4 with IMO is TSTARTIMO (=7us),

            and "Hardware startup" time when starting with ILO is TSTARTILO1 (=2ms),

            Is this my understanding correct?

            • 3. Re: PSoC4000Sの「TSTARTUP」のMAX値を教えてください
              e.pratt_1639216

              The physical startup times depend on the clock used and the procedure for startup. I know that the PSoC 4 has a startup delay for allowing the input crystal to stabilize, and I think this is a hardcoded delay of about 500ms. I think this is a software constraint to ensure correct operation however, and may not be a hardware constraint. I would test if this 500ms delay is in there by testing a board power-up time to see how long it takes from battery/power plug-in. More-than-likely I'm just wrong in thinking there is a half-second delay on powerup.

              If your CPU clock (the one running the system/CPU/HFCLK in the Clocks selection page) is the IMO it will have 7us and if it is the ILO it will have 2ms for startup times.

              Thus, the worst case would be 2 ms for startup and 7 us minimum for startup (this includes waking up from deep sleep and low power modes as well).

              tl;dr; Yes, I believe that is correct.