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.

12V or 24V input voltage regulator for Vout 19V

Other Parts Discussed in Thread: UCC28C42, UCC28C43, LM25118

Hi all,

I am trying to select a DC/DC non-isolated converter that will work with 12V or 24V DC input voltage

The Vout should be 19V DC and the output current 0.5A 

I guess that a buck/boost converter could maintain the output voltage in both cases, 12V or 24V of input voltage. My concern is when the input voltage is 12V because it is 7V below the required 19V of output

Is a buck/boost converter a suitable component for this application?

Thank You!

  • Hi Jesus, a buck/boost can either buck or boost as required, depending on the duty cycle of the switch, so it is the obvious choice for this application.

    One thing to note about the buck/boost is that the output is either inverted or referenced to the positive rail. Most applications require a positive voltage referenced to the negative rail, and for this reason, a flyback is often used instead of a buck boost, with the extra winding on the magnetic providing inversion. 

    TI devices such as the UCC28c42 or UCC28c43 can be easily configured to drive such a circuit.

    Thanks

    Billy

  • Hello Billy,

    By using the WEBENCH Designer from TI, I obtain a footprint of 1251 mm^2 with the flyback UCC28C43. This is a large footprint, more than 40 components and a transformer

    But the same WEBENCH provides other options like the wide range buck boost converter LM25118 with only 426 mm^2 footprint and 30 components

    I should use the smallest footprint option without reducing drastically efficiency

    Then, is there any other good option with a small footprint?

    Thank You!