• State
  • Replies 1 reply
  • Subscribers 47 subscribers
  • Views 37 views
  • Users 0 members are here
Support feedback
Options
Options
Related

TLC272: Technical Assistance Required ----- P/N: TLC272CP

Usman Niazi
Prodigy 240 points
Part Number: TLC272

Tool/software:

Hello Team,

One of our customers purchased 500 units of TLC272CP and claimed due to following reason,

--------------

The following error pattern emerged:
- With the 15V power supply, only 1.9V instead of 15V is measured (see following)


- If the TLC272CP with production lot 47AKTVM is replaced with an IC from lot 21AKECM, the circuit works again as intended (15V = 15V)
- So far, the error has only occurred with ICs with the production lot 47AKTVM

During the final test of production, 14 circuits were sorted out and repaired.
The stock of the TLC272CP with lot 47AKTVM of 276 pieces was blocked.

The ICs were ordered from Mouser with our order number 10250016.

It would be nice if we could order or have replaced 300 pieces of TLC272CP that are not from lot 47AKTVM.
I ask you to inform me about the next steps.

--------------

Can you please advise if you can assist the customer? Thank you.

Defective part 

Functioning part

Part comes from following tracing,

DC: 2430 

LC: 4136231WDH 

Mouser PO: 029-A8405

Best,

Usman

417173 

  • 0
    TI__Guru* 76691 points

    Hi Usman,

    Usman Niazi said:
    - If the TLC272CP with production lot 47AKTVM is replaced with an IC from lot 21AKECM, the circuit works again as intended (15V = 15V)
    - So far, the error has only occurred with ICs with the production lot 47AKTVM

    I think that the circuit has several design issues to be addressed in addition to the op amp (see PCN link). The latest op amp has slight output characteristic vs. pre-PCN part and it will behave differently. But the issues are mainly from the design of series regulator, which has many issues, see the comments below. The post-PCN TLC272CP is a RRIO op amp; the pre-PCN TLC272CP is either RRI nor RRO op amp. The op amp was "working" because of the previous non RRO characteristics, which mask the proper design of the series regulator.  

    In addition, PCN was issued in this part, that may explain why the other design issues are revealed in this case. And the date code in the part indicated that "defective" op amp (manufacture in July, 2024) is post-PCN type.  

    https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/5388/PCN20230608002.1.pdf

    There is nothing wrong with the post-PCN TLC272 op amp for the application. You may have to re-spin the PCB design and fix all the design issues in the existing circuit. Please let us know how you would proceed. 

    Best,

    Raymond