You cannot use negative feedback with a comparator since it does not have "frequency compensation" like used in an opamp.
How does your PP3 charger know if the "9V" battery has 6 cells or 7 cells?
You selected 8.4V as "blocks never overcharge" but if the battery has 6 cells then each cell is 1.4V and might be fully charged but if the battery has 7 cells then it is no where near fully charged.
A PP3 battery such a high internal resistance so if it is charged at a fairly high current for "fast charging" then each cell reaches 1.4V long before they are fully charged.
Hi AG
Most modern PP3 are 8.4 blocks. Seven cells.
Ansmann recommend MAX charge @ 10.15V.
I have three cheap(not really) Camelion Chinese 8.4 blocks that have loved the way I charge them.
Easily got around 500 to 700 cycles. No sweat.
Been charging and discharging for three years now. Never a failure. They just "wear out" or gradually loose Capacity.
Proper PP3 chargers are hard to find.
That is why there are very few on the Market worldwide
A little PP3 is like a cold Woman....sort of.
Umm..like....Don't excite me or make HOT?
Just charge me normally and quickly and look after me...
When I am at Terminal Voltage.....keep me there forever.
Then I can look after you forever too
Sigh
I'm in love with a sexy, charged PP3. PP3 is the one. PP3 might not have an hourglass figure.....she never gets HOT, just there for me.
So, there, is the confirmation that I have officially gone mad.
Somebody shoot me please
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