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TL783: TL783CKCSE3

Kartik Pagar
Prodigy 30 points
Part Number: TL783
Other Parts Discussed in Thread: TPS7A43

Tool/software:

Hi,

This is regarding MPN - TL783CKCSE3

My Requirement are:

  1. VIN=6 TO 36V
  2. VOUT = 5V
  3. IOUT= 30mA
  4. 65V Load Dump case will be there at input for 400ms approx.
  5. The part should be fully ROHS complaint without any exemption.

 

Following are my queries:

  1. Will this MPN is good to select considering all above requirement or do you suggest any other part?

If this part is good to select I have following queries:

  1. Should I consider operating temperature 125degC or 150degC?
  2. Is Reverse polarity protection is there or not
  3. I can see in datasheet thermal shutdown protection is present, can you please share the thermal shutdown temperature & hysteresis of thermal shutdown.
  4. Can you please share quiescent current Vs Output Voltage curve
  5. I can see in datasheet the if Input to output differential voltage is less than 25V then output current is limited to less than 700mA (Refer note 3 at  page no. 5 ), do you see any problem in my requirement of 30mA as in case of VIN = 6-25V the Input to Output differential voltage is less than 25V.
  6. Can you please provide the curve for Dropout Voltage Vs Output Current.
  7. Can you please share the PSRR value.
  • 0
    TI__Genius 13790 points

    Hi 

    1. TPS7A4001DGNR is a good alternative to TL783CKCSE3. It is a 100V, 50 mA device, RoHS compliant and can handle the load dump condition
    2. For both OPNs, consider 125 degC. However, the suggested device, TPS7A40 has thermal shutdown which protects the device for junction temperature at 170 degC which gives you more room for worst case
    3. TL783 does not. TPS7A40 has abs max on OUT as 105 degC. It can also handle reverse current up to 2.5 mA. This offers some reverse polarity protection

    Data for 3-7 are not available for the TL783 necause this is an older devie. The coresponding values for the replacement TPS7A40 are shown in the datasheet.

    Thanks

    Ishaan

  • 0 in reply to Ishaan Shetye
    Intellectual 290 points

    Hello Ishaan,

    Kartik & I working in the same project.

    I have some queries regarding the reply you have sent.

    1. The TPS7A4001DGNR has minimum input voltage of 7V but in our requirement min input voltage is 6V.

    2. I forgot to tell you that this IC will be used in Genset application & in our case one of the requirement is the Input voltage can go dip up to 3V & TPS7A4001DGNR cannot cater this requirement but TL783 has minimum input voltage has 1.25V which can cater our requirement.

    3. The TPS7A4001DGNR has higher RTHJA as compared to TL783 so in case of load dump the TPS7A4001DGNR cannot able to meet the required power dissipation whereas TL783 has very less RTHJA & able to meet the required power dissipation.

    Let me know your thoughts on above three points.

    My next que is Can I use this IC  for new design considering the above three points or do you still suggest some other IC considering the requirement that are there in trail conversion in addition to above three requirement.

    If I can use this IC, can you please check from your team regarding the data from 3-7 that mentioned in trail conversation. It will be helpful if you can provide this data.

    Thanks & Regards,

    Ajay

  • 0 in reply to Ajay Sahu
    Intellectual 290 points

    Hello Ishaan,

    Just to correction on above conversation Minimum Input voltage is not mentioned in datasheet of TL783, Can you please confirm on this?

  • 0 in reply to Ajay Sahu
    Intellectual 290 points

    Hello Ishaan,

    I have found one more part i.e. TPS7A43 looks good as better in comparison with TPS7A4001DGNR .

    Let me know your thoughts on this as well.

    I need one more help if TPS7A4 & TL783 part looks ok, then in case of load dump how to find allowed power dissipation as we cannot use the RTHJA mentioned in the datasheet because the load dump pulse is not for continuous duration. So I need some allowed power pulse curve for the load dump pulse duration. Please find the load dump pulse duration in below image.

    Consider the Max voltage as 63V as MOV is clamping at the input of LDO.

  • 0 in reply to Ajay Sahu
    TI__Genius 13790 points
    Ajay Sahu said:
    I have found one more part i.e. TPS7A43 looks good as better in comparison with TPS7A4001DGNR .

    That is definitely a better replacement given the operating conditions you mentioned.

    Ajay Sahu said:
    Let me know your thoughts on above three points.

    I agree with your 3 points here.

    Ajay Sahu said:
    My next que is Can I use this IC  for new design considering the above three points or do you still suggest some other IC considering the requirement that are there in trail conversion in addition to above three requirement.

    You can use the TL783 however we do not advise these for new projects. We strongly suggest the replacements I offered because TL783 is an old device and will eventually reach End Of Life sooner than the new devices. I think TPS7A43 is the best fit for your application.

    Ajay Sahu said:
    I need one more help if TPS7A4 & TL783 part looks ok, then in case of load dump how to find allowed power dissipation as we cannot use the RTHJA mentioned in the datasheet because the load dump pulse is not for continuous duration. So I need some allowed power pulse curve for the load dump pulse duration. Please find the load dump pulse duration in below image.

    I recommend using the time constant of the thermal shutdown circuit to determine this. It is around hundreds of microseconds. Given that the the load dump lasts for 2s, please make sure the current in this period is not so high as to cause thermal shutdown.

    Thanks

    Ishaan