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Can anyone suggest a TI part for a flyback or charger pump design?

Jeff Zhang22
Prodigy 170 points
Other Parts Discussed in Thread: UCC2805, LM5180, TPS61087, LM5022, LM3481, LM5155

Hi,

I need to design power supply but I don't see Webench tool providing a solution. 

the requirements is:

Vin = 5V (4.5~5.5V)

Vout = 100~200V

Iout = 100mA

Can anyone recommend a TI solution?

Thanks,

Jeff

  • 0
    TI__Expert 3095 points
    Hi Jeff,
    Do you require an isolated output or non-isolated output? In other do you have a common GND for both input and output voltage.
    If you require a non-isolated output a simple Boost converter should do the job.
    Thanks
    Joe Leisten
  • 0
    TI__Expert 8210 points
    Jeff

    These design specifications are not common. In order for webench to work fast and effectively it can only work with common design specifications.

    I recommend looking at UCC2805, which is a current mode PWM controller that can be configured as a boost or flyback. It's UVLO turn on abs max is 4.5V so it can be powered directly from Vin.

    Best Regards,
    Eric
  • 0 in reply to Eric Faraci
    Prodigy 170 points

    Hi Eric,

    Thanks for your recommendation. It doesn't need isolated output. The UCC2805 is interesting. What is the Fault soft-start?

    I prefer current mode controller with programmable soft-start. because it get power from USB port, the input power is limited at 5V 1.5A. The soft start is mast have feature. I don't want the system reset due to the inrush current of this power supply. 

    I found you have a reference design with TPS61087. It works at the current limit mode during start-up with power from USB. this is what I want it. 

    I also see anther part like LM5180, which is simplify the flyback design with integrated switch and primary side regulated. 

    what do you think about those parts? which one will be the best fit?

    Thanks,

    Jeff

  • 0 in reply to Jeff Zhang22
    TI__Expert 8210 points
    Jeff

    The fault soft start in UCC2805 is that when it comes out of a fault shutdown it has a soft start. The soft start cannot be externally programmed like some of the other TI controllers you highlighted. If this is a top feature you're looking for than I recommend going with one of them.

    I will have an expert on our boost controller products help identify which one would be best for your application.

    Best Regards,
    Eric
  • 0 in reply to Jeff Zhang22
    TI__Mastermind 40080 points

    Hi Jeff,

    TPS61087 is a low voltage rating boost converter.  As the output voltage is too high, you could use a boost controller in flyback topology to realize the conversion.. LM5022 is a good choice.

  • 0
    TI__Mastermind 21720 points

    Hi Jeff,

    Since you don't have an isolation requirement a good place to start is this reference design. It uses the LM3481 in a boost configuration with a charge-pump stacked on the output to achieve 200V on the output. This article covers the operation in this configuration. This LM3481 has fix internal soft-start. I think this should be enough soft-start time assuming the output capacitance is fairly small.

    The other option is use the LM5155 in the same configuration and is shown in this reference design. The LM5155 has external soft-start that can be programed as needed.

    Note that this design only requires a simple inductor and not a transformer like a flyback.

    Thanks,

    Garrett

  • 0 in reply to Garrett Roecker
    Prodigy 170 points
    Thanks Garrett!
    This is a interesting solution. I like it.
    I probably will try LM5155, because the reference design has higher output current.
    Thanks,
    Jeff