Chips & Tech.

Thursday, August 30, 2018

YX8018 ~about "guessing the operation"

→NB←! the following has pretty much nothing to do with the actual chip !!! ←
i just matched some known or guessed data into random simulation substitute

from what we can conclude ::

the device operates best at certain fixed supply voltage (there might be one built in to YX8018)
the best efficiency is occurring below the certain output power = you should not replace the inductor to lesser inductance one without making sure :
a) that there's enough power to drive the inductor (somewhat aided by the 1µF and 5µH caps inductors at the schematic) ,
b) that the inductor won't be driven into saturation
( ↑↑ ← both are primarily indicated by a notable drop in efficiency compared to initial -- however the lesser inductance does, by the idea, give a* higher output power and usually there is some efficiency drop for "trade" to such* )
the onboard inductor in my particular solar lantern has 4Ω series resistance (it might be useful to protect the mosfet from peak power ? from accidental out of cycle re-trigger . . . or provide some voltage regulation for more up to charge battery) , otherwise there's a plenty of room to install a better inductor (such might also cause the over-voltage at the switch drain -- it must be tested out at max input power)

[Eop]

Tuesday, August 28, 2018

Predicate research for using the LED as a photodiode

in prior of doing the following i measured the target Blue LED that did output some millivolts but no nanoamps , then a high efficiency Blue LED that i used for below experiments (← the series array of theses gave pretty much alike data than the single one) . . . then the iR LED parallel array from the (used for . . . ?? pre-clearing the image in) laser printer , it output over 1V and i guess several microamps . . .

. . . all that illuminated from the narrow beam 1W Power LED

the conflicting data (with web) is that when illuminating the LED it outputs fw.-polarity voltage -- e.g. [+] from anode and [-] from cathode * . . . all 3-types of the above without the exception ???

Note* :: no conflict (http://www.ques10.com/p/9330/explain-with-neat-diagram-construction-and-worki-1/) , conflict ( . . . there was a site that actually textually claimed that ? intentionally or not . . . can't re-find it at this time . . . and it was not the only one such . . .)

first couple of web found setups (slightly modified)