Hi guys, I have built a DC-DC Boost circuit with MC33063AP. The schematic is as shown below:
My R1 is 11K, and R2 is 330K, according to the equation Vout=1.25*(1+R2/R1), it should give me 38.75V, but instead of that, it gives me 36.8V. 36.8V is fine as well, because I have replaced two of the inductors into one 220uH inductor, and also the last three capacitors into one 470uF capacitor. However, I have found out the voltage is not stable, from the oscilloscope, I can see the voltage is jumping between 3 figures: 36.4V, 36.8V and 37.2V…
Does anyone knows why? I am thinking that it is from the capacitor charge and discharge, but I am not sure how to fix it.
Thank you!
My R1 is 11K, and R2 is 330K, according to the equation Vout=1.25*(1+R2/R1), it should give me 38.75V, but instead of that, it gives me 36.8V. 36.8V is fine as well, because I have replaced two of the inductors into one 220uH inductor, and also the last three capacitors into one 470uF capacitor. However, I have found out the voltage is not stable, from the oscilloscope, I can see the voltage is jumping between 3 figures: 36.4V, 36.8V and 37.2V…
Does anyone knows why? I am thinking that it is from the capacitor charge and discharge, but I am not sure how to fix it.
Thank you!
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