TPS5410: Power ON issue

Part Number: TPS5410

Hi TI Team,

Actually, our design is for Solar tracking system. The main power source is from State board grid power source. That grid power goes to an inverter and then AC-DC Meanwell Power supply (RS-100-24). AC-DC will generate 24V DC output for our device only. Our device consumes 24V@400mA initially and the 24V@100mA regular consumption. I have attached the Datasheet for the AC-DC power supply for your reference.

I have used the TPS5410 buck converter in my industrial field design to generate the 5V and 3.3V output from 24V Vin.

Issue: The problem is whenever the grid power gets OFF, our device is also getting off. But when the grid power is back, our device doesn't turn ON. We have noticed that the input supply 24V is available onboard but the buck converter doesn't turn ON. Means no output voltage generated from the TPS5410 (3.3V). Due to that, the device is not getting ON. Manual intervention (manual Power ON-OFF) is required to power ON the device.

Kindly provide a suitable solution to resolve this issue.

Regards,

Mrudang

RS-100-spec.pdf

  • Hi

    have you try to power on and off the TPS5410 only by other 24Vdc souce, and what's the result?

    you can also monitor the waveform of PH and ENA see the waevform when you power up and power down see .

    Thanks

  • Hi Daniel,

    We have tested on 24VDC, and we haven't face this issue. Thi issue occurs only on the field, and we don't have a timeline when the power goes and come back. So, we can't monitor PH and ENA waveform.

    Do you see anything wrong with the design? What could be creating an issue here?

    Mrudang

  • Hi 

    is it 100% or partial of the product have the issue?  I didn't see the issue from schematic, if you can measure the votlage by voltagemeter , you can check EN votlage when 24V is applied. 

    Thanks 

  • Ho Daniel,

    Is there any issue with compensation network calculations, AL-EL capacitor on the load side for device stability in our intended use case? We have observed this issue in the field only not during in-house testing.

    Can I have a call with you for a use-case application and a better understanding?

    Mrudang

    +91 99252-20048

  • HI

    if the compensation or loop issue, it will be found when you use 24V DC souce , the loop won't change by input souce change, but 

    1. the AL-EL capacitance will chagne a lot by temperature.

    2. Input impedance of TPS5410 need to match the output impedance of 24V DC souce to avoid the input resonant by unmatched impedance of input and output. but it will be easily solved by add a AL-EL cap at input.

    if no waveform to identify the issue, it will be hard to guess the root cause of the issue.

    Thanks 

  • Hi Daniel,

    I have few queries, kindly provide your valuable response. 

    1. We do not think that impedance mismatch for o/p and i/p for 24V, as we have measured 24V at i/p side. What value you suggest to add a capacitor on i/p side? 
    2. Can we add a pull-up resistor 10K with 5V on the EN signal? Will it help us?
    3. It's been 4-5 yrs the device is installed on-field and after 4-5 yrs of running condition, the issue has occurred the first time and repeat thereafter. Is it possible to have any MTBF effect on 3.3 output IC (U2 only) only due to switching i/p power ON/OFF from the grid power side? I believe it should impact both U2 and U3. Please confirm.
    4. Is it any issue with generating the 3.3V from 24V using the TPS5410 IC?
    5. What exactly you would like to capture on the oscilloscope and how it will help us? If you want we can capture the voltage value using DMM.

    Mrudang

  • Hi ,

    Have you got a chance to go through my few queries in the previous response?

    Mrudang

  • HI

    1. suggest add a 47uF 50V AL

    2. yes, you can try , at least you can check whether it is ENA issue.

    3 If the problem is only happened after 4-5yr use, my question is this issue is 100% happen or it failed in very limited number? As I recommend before, pls help to catch the issue waveform including the PH, VO and EN. DMM can only check the EN, VO voltage, no help for PH. One more thing is whether change the new silicon can fixed this issue?

    4. I don't see the issue from you schematic.

    pls refer 3.

    Thanks

  • HI Daniel,

    Thanks for the response. I will check, test and update you soon.

    Mrudang

  • Hi

    Thanks, waiting for your update

  • HI

    I didn't see the update, I will close this question, you can reopen it if you need

    Thanks