On 11/30/2018 2:29 AM, RussellMc wrote: > 4.1V CV is wholly acceptable - and results in longer cycle life than the > more usual 4.2V. > As that is below the lowest IC programmed Vreg and as the terminate light= s > never light it's not obvious what is happening. > > The charger IC requires a minimum 0.3v headroom. > [ *Datasheet > page 3 secti= on > 1.0, supply voltage =3D *VREG(Typical)+0.3V ] > What supply voltage are you using? Direct 5.0V from a USB charger. > "Trickle" is acceptable at Vmax of < to << of Vmax (nominally 4.2V). > At 4.1V I'd want to be sure that temperature excursions would be accounte= d > for and at 4.0V you are probably safe to apply voltage constantly. > Constantly applied 4.2V is liable to lead to rapid cell degradation. I've run several charge cycles at 1C and I can't detect any temperature=20 increase (as I feel it, not measured). I'm really not concerned about=20 temperature And I can live with the battery life at the 4.1V it's getting up to. =20 Biggest concern is being able to indicate to the user when the charge is=20 complete. > > It does not sound as if this applies, but: If you are loading the battery > while charging and if Ichg is also supplying this load then if Iload >> > Iterminate_programmed then charging will never terminate. No load during charging. Well, it can be on when charging, but based on=20 how it will be used (wearable), the user should be charging when it's=20 powered off. > > > Russell --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .