Hi,
That's pretty good really. Just one small thing, notice the other circuit had a 1k resistor on the output of the reference. So you have to move the 10uf cap to the left then install a 1k resistor from the top of the 10uf to the 1M resistor and non inverting input so it is just like the other circuit.
The 4.15v measurement is at point A common to the battery negative terminal ( -Battery ).
On the new schematic below, the 4.15v is between points A and B, and is measured when the battery is not yet fully charged.
Of course if you set that to 4.15v then you must set the other voltage setting to charge the battery to around 4.16v or the voltage monitor LED may never turn on.
You may not need the whole 10v, that's just there in order to have some value shown. You might be able to use 8v or 9v, but if the regulator gets hot then use a heat sink. The second LM317 can be a regular type in the original circuit but since you now use a TL431 you dont need it. You never mentioned that you also have TL431's on hand too.
That's pretty good really. Just one small thing, notice the other circuit had a 1k resistor on the output of the reference. So you have to move the 10uf cap to the left then install a 1k resistor from the top of the 10uf to the 1M resistor and non inverting input so it is just like the other circuit.
The 4.15v measurement is at point A common to the battery negative terminal ( -Battery ).
On the new schematic below, the 4.15v is between points A and B, and is measured when the battery is not yet fully charged.
Of course if you set that to 4.15v then you must set the other voltage setting to charge the battery to around 4.16v or the voltage monitor LED may never turn on.
You may not need the whole 10v, that's just there in order to have some value shown. You might be able to use 8v or 9v, but if the regulator gets hot then use a heat sink. The second LM317 can be a regular type in the original circuit but since you now use a TL431 you dont need it. You never mentioned that you also have TL431's on hand too.
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