• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 62 subscribers
  • Views 470 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.

TPS60150: Output capacitance & Pre-Bias

T Kishi
Genius 4425 points

Part Number: TPS60150

Hi

My Customer has question.

The customer says it can not be adopted unless the contents of the question clear.
Please give priority to this question and respond.

1.In the data sheet of TPS60150, Co min = 2.2 uF is stated.
　This effective capacitance includes any DC bias effects？

2.If it falls below 2.2 uF, is there a possibility that the TPS 60150 malfunctions?
　For example, "output oscillation" and "breakage" etc.
　Capacitor the customer is about to implement may not satisfy 2.2 μF due to its characteristics.
　customer is concerned that it will lead to "oscillation" and "breakage".

※Please especially please give priority to 1 and 2.

3.The customer use it with Vin = 3.3 / Vout = 5 V/, but there is a possibility that the Vin may become 0 V.
　At that time, Vin = 0 V / Vout ? 5 V/Load=Open.
　Does TPS60150 get damaged?

4.Is there no problem even if I operate the TPS60150 in a state where the output has a voltage (Pre-Bias)?

Best Regard

  • 0
    TI__Guru* 79475 points

    Thank you for considering the TPS60150 in your design.  The following are answers to your questions in the same order.

    1.  The Co min of 2.2uF is based on typical X7R or X5R capacitors for stability considerations, which takes into accounts the DC bias effects of these type of capacitors.  To use a standard 2.2uF X5R/X7R, the circuit will be stable.   However, the output ripples can be reduced if more capacitors are used for the output.

    2. If it is within the tolerance of the X5R/X7R, no concern of damage or oscillation.  If use a 2.2uF labeled X5R/X7R, I would recommend use not worse than +/-10% tolerance capacitors.   As mentioned above, if the value is below the 2.2uF, Vout ripple may be high.

    3. The device will not be damaged under such condition.

    4. The device can operate with prebias condition. 

    Again, thanks.

  • 0 in reply to Youhao Xi
    Genius 4425 points
    Hi Youhao

    Thank you for reply! I deeply appreciate your prompt response!

    Please add one point only.
    Customers plan to use this Condenser.
    〇C1005X5R1A225KT
    DC bias is bad (5 V / about 0.5 uF)
    Will damage or oscillation not occur also in this Capacitor?
    In the worst case customers can implement up to two.

    Best regard