MPQ4470 Reñation between VFB and VREF

[e.perezdelasheras]

Hi everyone,

I’m currently working on a project and need some help understanding the relationship between the reference voltage (VRef) and the feedback voltage (VFB) in MPQ4470 . I’ve gone through the datasheet, but I couldn’t find any equations or detailed explanations regarding how these two voltages are related.

Could someone please explain how VRef and VFB interact with each other? Any equations or practical examples would be greatly appreciated.

Thanks in advance for your help!

[eduardo.FAE]

Hello e.perezdelasheras,

I believe that Vref and Vfb are supposed to be equal to each other. Vref should remain stable whereas Vfb will fluctuate going above and below Vref. Vfb is simply the voltage for the voltage divider r1 and r2, Vfb = Vo(r2/(r1+r2)). If you equated Vref to the Vfb equation and solved algebraically for R1 you would be left with the resistor sizing equation below.