boylesg
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Your question about Excel is not clear. Can you upload a little more explanation on it?
The inductance values have been selected for application circuits shown on previous data sheet pages, please review. They should be related to the Lmin calculation.
I am aware that they have provided example application circuits and that 170uH is the inductance value used in one such example.All inductance values have been selected for specific circuit parameters of these application circuits e.g. supply voltage, output current, switching frequency.
But this table is for the formulas used to calculate the various component values in ANY application circuit. What has the 170uH inductance value got to do with other application circuits? For what purpose is it even listed in the table of generic forumals?
I agree to the consideration.But this table is for the formulas used to calculate the various component values in ANY application circuit. What has the 170uH inductance value got to do with other application circuits? For what purpose is it even listed in the table of generic forumals?
This is an additional information provided just on same page. If you are not calculating for those circuits for which they are meant simply forget those values.
I agree to the consideration.
déjà vu https://www.edaboard.com/threads/262768/ (posts #2 - #5)
I already used MC34063 as previously mentioned, but I won't suggest it as a "simple switcher", particularly not for a beginner.
A late comment about the table in #4. It can't be found in a recent MC34063A datasheet. I have Rev.6 (12 years old) and latest Rev23, both don't show the inductor values inside the calculation table. So we are apperently discussing a documentation wrongness of a last millenium datasheet.
https://www.onsemi.com/pub/Collateral/MC34063A-D.PDF
Some application circuits have an additional 1 µH/100µF output filter. Its placed outside the feedback loop and shouldn't affect the device behaviour too much.
A problem that apparently shows in your tests is instability with without load. DeepOne suggested to provide 5 mA minimum load for stable operation.
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