• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 62 subscribers
  • Views 855 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

LP5910: Using LP5910 as drop-in replacement for TPS720xx

Ronald Rehfinger
Intellectual 290 points
Part Number: LP5910
Other Parts Discussed in Thread: TPS720,

We currently use a TPS72010 and a TPS72012 to generate 1.0V and 1.2V outputs from a 1.5V supply. The BIAS-pin of the TPS720 is connected to 3.3V. While this generally works well and saves a lot of power compared to an LDO that is sourced from 3.3V, we have the problem that we can not control the sequence of the BIAS and VIN voltage sources. Since the TPS720 has the "VIN ≤ VBIAS under all conditions" requirement, we want to replace the device.

The LP5910 would fit nicely into the existing design, the TPS720 BIAS would connect to the LP5910 EN pin, which would be OK, all other pins match. The LP5910 would be sourced solely by the 1,5V rail, which would be within the Input Voltage Range.

But I'm unsure if the LP5910 would work with a fixed output of 1.2V when sourced with 1,5V. We would only use about 100mA.

Another problem is that the LP5910  seems to be listed in all the selection tables to be available with 1.2V fixed output, but there does not seem to be an according order option. How would I buy a LP5910  with 1.2V output?

Regards

  • 0
    TI__Guru 55940 points
    Hi Ronald,

    You are correct that LP5910 does seem to fit as a drop in replacement in the DRV package; however, unfortunately the 1.2 V version is only available in the YKA package at this time.

    In your layout, what nets do you have Pins 2 and 3 tied to? We may be able to find another drop in replacement for you that will fit the 1.2 V rail.

    Very Respectfully,
    Ryan
  • 0 in reply to Ryan Eslinger
    Intellectual 290 points
    Hi Ryan,

    I noticed the YKA packages, but unfortunately our manufacturer won't be happy when I would use them. Is there a time frame when the other voltages will be available in the DRV package?

    In the existing design the TPS720 Pin 2 (NC) is not connected , Pin 3 (EN) is connected to 1.5V. If there is another alternative part that I just didn't found I would be happy, and even more if it would also cover the 1.0V.

    Thanks & regards,
    Ronald
  • 0 in reply to Ronald Rehfinger
    TI__Guru 55940 points
    Hi Ronald,

    Your search was correct, unfortunately pin 3 is commonly GND for this package and will therefore not work for your current layout.

    We do not have a time frame for the 1.2 V version of LP5910 to be released in the DRV package.

    Very Respectfully,
    Ryan
  • 0 in reply to Ryan Eslinger
    Intellectual 290 points
    Hi Ryan,

    thanks for your efforts. Maybe I'll just stick with the LP5910-1.0 for the 1.0V output. Still have to look for a solution for the 1.2V output, though.

    A remark: The BIAS feature is not included in the "Special Features" list in the parametric table. It may be useful to add that.

    Regards,
    Ronald