rompelstilchen
Full Member level 2
Hello,
I use a 3.7V 16850 cell that gets boosted to 9V (board : https://www.aliexpress.com/item/32844818160.html?spm=a2g0s.9042311.0.0.27424c4dSXahMo)
as I sometime, have to recharge my cell, I thought I'd use 3.3V coming out of a LM3940 but the booster output drops to 4.4V while the output voltage of the LM3940 drops from 4.0V to 2.2V
I measured the curent while using the battery : 50mA and as I measure the current while using the LM3940, I get 0mA (my voltmeter precision beeing limited)
can someone explain to me what's going on ? the LM3940 can go up to 1A, I tried another one, same problem, how can I fix this ?
thanks
I use a 3.7V 16850 cell that gets boosted to 9V (board : https://www.aliexpress.com/item/32844818160.html?spm=a2g0s.9042311.0.0.27424c4dSXahMo)
as I sometime, have to recharge my cell, I thought I'd use 3.3V coming out of a LM3940 but the booster output drops to 4.4V while the output voltage of the LM3940 drops from 4.0V to 2.2V
I measured the curent while using the battery : 50mA and as I measure the current while using the LM3940, I get 0mA (my voltmeter precision beeing limited)
can someone explain to me what's going on ? the LM3940 can go up to 1A, I tried another one, same problem, how can I fix this ?
thanks
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