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My MSP432 is drawing 170 mA. Why?

Prodigy 125 points

Replies: 20

Views: 6519

Hi.

I got MSP432 launchpad a week ago.

Studying MSP430 LaunchPad Workshop Course Workbook as my textbook. There was no problem whatsoever. But in lab 7(Energy trace) I've encountered a problem.

After flashing solution of lab_07b_lpm_timer project. I ran EnergyTrace. But EnergyTrace immediately stops and it says "Target current exceeded with the maximum current (75mA) supported by EnergyTrace."

Huh?

So I actually measured current and voltage with my multimeters and the uc was drawing 170 mA. Even in the reset state.

No external circuitry has ever connected to my launchpad. Even no single jumper wire.

What could be a cause of this problem? ESD?

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Sep. 3,

Planning to get another MSP432 LaunchPad and MSP432P401RIPZ(LQFP100) next week.

I will update this post after replacing MSP432 chip on this LaunchPad board.

Thanks to everyone who cared about my problem.

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Sep. 10,

Replaced old MSP432 with the new one. It turns out that the MSP432 was the problem. After replacing, current consumption of the board drop to 1.5 uA, with debugger connected and all default jumpers connected. Very happy with it.

  • What happens if you flash another (already tested) program onto the processor and where did you measure the current/voltage?


  • In reply to Dennis Eichmann:

    Hello Dennis.

    After reading your reply I flashed few verified programs to MSP432 and ran them.

    lab_02a: "hello world" via debug CCS console. - Works: hello world is printed -
    lab_02b: blink led using gpio and software delay. - Works: LED binks-
    lab_06c: Timer directly drives Led, also utilising port map. - Works: LED blinks -

    Few more measurements:
    While 3V3 Jumper disconnected. 3V3 from XDS110-ET was 3.29 V
    While 3V3 Jumper is connected. 3V3 from XDS110-ET was 3.23 V (voltage drop due to 170 mA current draw maybe)
    While Blinking Blue LED on P2.2:
    Port output high voltage: 3.00 V
    Port output low voltage: 0.01 V

    So debug module, GPIO and timer works. Still, in every case current draw is measured about 170 mA. (pretty constant, only goes up few mA when LED turns on)
  • In reply to Seungwon Lee:

    Do you measure the current by removing the 3.3V jumper and hooking your probes to it?

    Did you double check if all other jumpers are in the correct position? For example the three LED jumpers? Maybe inserted 90 degrees to the normal position and shorting two outputs of the MSP?


  • In reply to Dennis Eichmann:

    Yes. I used that header pins for the measurement.

    This is my measurement setup. lab_06c: Timer directly drives LED is running.

    Left meter: measuring current in Amps range.

    Right meter: measuring voltage of 3v3 rail.

    No 90º jumpers.

    FYI. surface temperature of the MSP432 chip was about 52 ℃ (126℉). delta T ≈ +29 ℃

  • In reply to Seungwon Lee:

    Seungwon,
    170mA is definitely too high, more than maximum current draw specified on the MSP432P401R. Can you do a couple of experiments:
    - In one of your LED examples, after verifying that the code works, remove all LED jumpers. Does the current still read 170mA?
    - Try out this LPM3 code example dev.ti.com/tirex , which ideally should put the device down to LPM3, consuming only 850nA. If you still read several mA of current at this point, most likely we're looking at a short somewhere on the board.
    ~Dung

    www.ti.com/msp

  • In reply to Dung Dang:

    Dung,

    Sure.

    I did experiments you said.

    Not pictured but removing jumpers while running blink program did not affected to current readings. Just LED current fluctuations are gone. Still around 170 mA.

    I imported LPM3 example to my workspace and flashed to MSP432. Example from "MSPWare: msp432p401_pcm_02 Enter LPM3 (ARM Deep Sleep Mode) with ACLK = REFO"
    Also every jumpers are removed.

    Curiously entering LPM3 drew more current. it's 190 mA now.

    While pressing reset button 170 mA.

    Video: