• State TI Thinks Resolved
  • Locked Locked
  • Replies 8 replies
  • Answers 3 answers
  • Subscribers 63 subscribers
  • Views 102 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.

TPS53689T: IC Not getting detected in Fusion

Siddhi Sawant
Intellectual 400 points
Part Number: TPS53689T

Tool/software:

Hi Team,

We are using TPS53689T multiphase controller IC. 

The IC is not getting detected in Fusion power designer software.

Earlier it was detecting, but now it is not detecting.

We checked the output of Vref (pin 40). It was 0.7V, but expected is 1.5V, hence we replaced the IC and soldered new IC.

Now we are getting 1.5V at Vref pin, but still the IC is not getting detected.

Checked the voltage at Address pin (pin 34), we are getting 0.6V which is expected as we have used (30.1k for RHA and 20k for RLA for 8+0 config as per datasheet).

What could be the reason for this?

Thanks,

Siddhi

  • 0
    Intellectual 400 points

    One more observation is, at CSPIN pin 37, we are getting 6.5V and at pin 38 we are getting 12V. 

    Can this be the reason for IC not getting detected?

    (FYI, same issue is observed on 2 boards).

  • 0 in reply to Siddhi Sawant
    TI__Intellectual 1530 points

    Hi Siddhi,

    As communicated in email, potential of pins 37 and 38 (VIN_CSNIN and CSPIN) should be close by. 

    I will advice you to remove R975 & R965 and then directly short the two pins. 

    It is possible that this device is also damaged. 

    If you  are interested in sensing VSYS, please use TPS53689T48V. 

    Regards

    Vasav 

  • 0 in reply to Vasav Gautam
    Intellectual 400 points

    Hi Vasav,

    We tried to short pin 37 and 38. Now we are getting 12V for both pins.

    But, still the IC is not getting detected in Fusion.

    Thanks,

    Siddhi

  • 0 in reply to Siddhi Sawant
    Intellectual 400 points

    Hi Vasav,

    We replaced the IC and mounted new IC.

    Now the IC is getting detected, but we are getting Vout as zero volts.

    We have observed 2.7 V at ACSP8(pin 30) & at ACSP7(pin 29). For all other ACSPx pins, we are getting 1.5V

    We are getting below mentioned faults. 

     

    Also, in monitor tab, we are getting 81A in Ph7 & Ph8.

    What could be the reason for this?

    Thanks, 

    Siddhi

  • 0 in reply to Siddhi Sawant
    TI__Intellectual 1530 points

    Hi Siddhi,

    CSP going high is a power stag fault. 

    For your confirmation purpose you can disable these two power stages and check.

    By the way, it is also showing OCL. Since device has not even booted and you are hitting OCL, gives impression of some short on the board. This could be TLVR short, or some PS is damaged. Of course the short may be at some other place also.

    Regards

    Vasav 

  • 0 in reply to Vasav Gautam
    Intellectual 400 points

    Hi Vasav,

    We tried to disable Ph 7 & Ph 8 phase. Now we were getting OVF fault, so we increased OVF fixed value from 2.1V to 3.1V, and now we are getting 1.92V in Fusion as shown below, but when checked using multimeter, we are getting 2.6V as this rail, now we are getting OVPB_CHA fault, TAOLOW_CHA as shown below.

    Also, the VR are getting very hot.

    We checked for the shorts, but there is no short found on the board.

    What could be the reason for this?

    Thanks,

    Siddhi

  • 0 in reply to Siddhi Sawant
    TI__Intellectual 1530 points

    Hi Siddhi,

    This is a debug activity, which requires many combination of tests. 

    My first guess is that TLVR is short. Most likely, inductors with Ph 7 or 8 are are culprit. 

    What was the current in each phase?

    Regards

    Vasav 

  • 0 in reply to Vasav Gautam
    TI__Intellectual 1530 points

    closing as it is already solved.