• State
  • Locked Locked
  • Replies 4 replies
  • Subscribers 79 subscribers
  • Views 1076 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

MSP430FR5969: MSP430FR5969 minimum and maximum Active Mode Supply Current

MichRFT
Expert 2110 points

Part Number: MSP430FR5969

Hello,

Can TI indicate the Active Mode Supply Current Minimum and Maximum current values?

In table 5.4 of the datasheet only Typ and some Max values are indicated.

I find a ratio 1.5 between lowest and highest currents when I test many of our PCBAs with exactly the same software. I check the execution time and it is always the same on all PCBAs.

So I would like to know if the 1.5 ratio is normal?

Best regards.

Mich

  • 0
    TI__Guru**** 223427 points
    Hello Mich,

    There should not be a 50% difference between identical MSP430 units operating the same application software. Can you please further comment on your application, possibly providing schematics? How are you measuring the current and are you confident that all units are operating under the same conditions without getting stuck in a LPM or fault flag loop?

    Regards,
    Ryan
  • 0 in reply to Ryan Brown1
    Expert 2110 points

    Hello Ryan,

    Thanks for your answer. So more work is needed.

    I quite confident that all units operate under the same condition but of course every things need to be checked.

    Here is my test: without algorithm running all PCBs have the same average current between 8.5 and 9µA. Then I activate the algorithm and I set to 0 all sensors values to have the same input for all PCBAs. I measure average current between 20 and 30µA.

    All exceptions are superwised, SYSRSTIV values are saved in a memory and can be readback to debug. I did not see any exception or watchdog.

    Best regards

    Mich

  • 0 in reply to MichRFT
    TI__Guru**** 223427 points
    Hello Mich,

    What modules are involved in this algorithm you refer to and can the code be reduced to reveal a specific portion which is causing the current difference? And what type of external sensors are connected? Have all unused pins been initialized for low power operation (Section 1.6/Table 1-4 of the User's Guide) and are external crystals involved in the design?

    Regards,
    Ryan
  • 0 in reply to Ryan Brown1
    Expert 2110 points
    Hello Ryan,
    I am using an accelerometer. To avoid different values between PCBAs, I set the accel values to 0. So the algorithm duration is always the same for all PCBAs but not the current. The only external crystal is a 32768Khz on LFXT to wake up the MSP by timer. MCLK is driven by DCO.
    No issue in LPM3 mode, always the same consumption for all PCBAs. JTAG are opened because not used (except if I need to check clock outputs for debug).
    I will do a while(1) loop to check the current if always in active mode. This loop will either contains nothing or a few code with "if condition" to see the effect of the pipeline.
    Best regards
    Mich

**Attention** This is a public forum