re-posted to charger forum as well... please ignore this post...
I'm trying to tweak an already existing design and I'm getting confusing results. I've got a Battery (using a bq20z95) 8.6V (4 cells) that I'm trying to charge with a bq24600 part. When I change VISET I get a change in the charging current but it always comes out lower than what the calculation says it should, what am I doing/expecting wrong? I've got a 210k/56k divider from Vref to the Iset pin (RSR = 0.01 ohm) which should give me 3.47A for charging (Vin = 12V) . VBAT is set for 8.4V The inductor is a SRP1040-2R2M 2.2uH. Which gives a Iripple of 0.95A (is too much ripple my issue?). Instead of 3.4A charging I get about 2.5A, I've tried some other resistor values instead of the 56k and always get lower than expected charging current... where did I go wrong?
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