I am trying to design the 5V application with MP8004. Refer to the Datasheet figure 9, can modify the R18 R17 to changethe Vout. for exsample, set R18 to 10K, R17 to 3K, it can set the Vout to about 5.4V right? and this device is not supported by MPS DCDC Designer. Is there any other design support? e.g. 5V/2A application etc. and how to calc and set the vlaue for R7 R8 C4 in 5V application with specific transformer？increasing the C4 value, it can improve the load capacity for Vout?
Thanks.
vout is set by 1.24V and the division ratio ofr R18 and R17. I would change R17 to 27.2k and leave everything else pretty much alone. The transformer maybe should be designed differently with few turns of thicker wire on the secondary to allow for higher output current, so roughly cut the turns in half. The D2 diode might need to be beefed up to a 5A type for the higher current.
Hi Cary,
I’m looking into your question.
Will follow up asap.
Thanks,
Cindy
Hi Cary,
Thanks for your question.
Yes, in order to set Vout, you’ll need to use the V_FB=1.21V and the resistor divider values to calculate for Vout.
If you use 10K and 3K on the output resistor divider, you will get ~5.24Vout.
The COMP pin is connected to an error amplifier circuit, the purpose is to improve stability of the part. It does not improve load capacity. I’d recommend using the values recommended in the typical application circuit, then adjusting values as necessary.
Thanks,
Cindy