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UCD3138A: 2-MHZ Reference specified in datasheet

Part Number: UCD3138A

Hi Champ,

I am asking for my customer.

It is specified DPWM could up to 2-MHz Switching Frequency.

Is it defined in -20 degree temp or 120 degree temp ?

Besides temp., is there any other factor affect the DPWM output frequency ?

Thanks and regards.

  • Johnny, the picture says it could up to 2MHz from  -20 degree to 120 degree. Temp is the only factor that would affect the frequency.

    Best Regards,


  • Johnny, the DPWM can actually switch faster than 2 MHz.  The speed actually being referred to is the rate at which the compensation filter can run, which is approximately 2 MHz.  Normally the filter runs every switching cycle, but this is not really necessary, depending on what bandwidth you need for the filter.  

    The graph is to show typical temperature variation of the UCD clock, and they were measuring it with the DPWM set at 2 MHz nominal as part of the test.  

    I can understand why this is all confusing, but that is how it is.