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Re: Is these LED status work ? ( LM317 Contant Current Charg
If the constant current is within the LED rating you do not need the diodes and resistor. Why do you need the LED? With the constant current, it will only indicate that there is a battery connected.
A cheaper way is to first calculate the voltage across the LED when it is lit. Usually 10 mA is a good current for them. Then calculate the resistor value as the LED voltage divided by the constant current minus 10 mA.
You can also use incandescent light bulbs. They will glow red with less than rated current and last longer.