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LM22675: When the output voltage is more than 5V

Part Number: LM22675

Hello.
I use LM22675 with the following specification.

Specification
  Vin: 21.6~25.1V  (TYP=24V)
  Vout: 10V
  Iout: 1A

There is the following description on page 8 of SNVS591L.
"If an output voltage of 5V or greater is required,
the -5.0 option can be used with an external voltage divider."

However, the output voltage is larger than 10V when I use LM22675MRX-5.0.
I think this reason is FB resistance of 9.93kohm in LM22675MRX-5.0.
5V/9.93kohm=500uA

There is the following description on page 13 of SNVS591L.
"For the -5.0 option, the total internal divider resistance is typically 9.93 kΩ."

I heard that I had better use LM22675MRX-ADJ for reason of the above when the output voltage is more than 5V.
This is the thing which I heard in 2009.
I heard that the data sheet will be revised, but it has not been yet revised.

In the case of the above (Vout=10V), is it correct to use LM22675MRX-ADJ?

Regards,
Dice-K

  • You can use either the -5V or the -ADJ.  The internal compensation for the -5V is

    slightly optimized for output voltage of >=5V; however both will work. 

    The data sheet has an equation for the FB divider in the case of using the -5V for higher output votages.