Non-isolated supply design, voltage problem
sir,
I designed 24VDC non-isolated power supply by using LNK306 with reference of AN37.I used 10uF 450V for Cin1 and Cin2. 1000uH is the input and output inductor. I used the circuit as per the Application note AN37. The problem is instead of 24V ,the output is 22.4V. How to get 24V exactly. and also I checked the output with AC mode of CRO.The 100mV noise is came. How do get 24V exact.I want to use this 24V with relay,and get Output 5VDC from this 24Vdc by using Linear regulator. Please provide some suggestion. my output capacitor is 100uF 63V.I used BYV26C freewheeling diode.Awaiting for your response
Comments
Sir
As per your spreadsheet of PI EXPERT software, I used R bias as 2.2K and R feedback as 25.6K. But the output is low 22.4V only.How do increase the output voltage.how do i get the exact 24V ? minimum noise preferred.
Based on my calculation, output will be close to 24V(higher than 24V) with 26.7K Rfb and 2.2k Rbias. But you have to trim Rfb and Rbias for the exactly 24V output. The output voltage will be increased with higher Rfb and lower Rbias, and the output voltage will be reduced with lower Rfb or higher Rbias.
sir,
Thank you so much I used 27K resistor as Rfb.I got 23.60V.I think that is enough. I used 28.2K (20K+8.2K) ,the output is 24.6V.
The output will be higher if you use higher Rfb or lower Rbias.
Thanks a lot for using Pi part.