i am on the way to develop a small battery powered 'gadget' as a hobby project.
and at the moment im searching for the right power management parts
my requirements are
Single Cell, Li-Ion / Li-Pol Battery, Capacity 1000mAh - 2200mAh
for my system i need 300mA @ 5V and 200mA @ 3.3V
the system must be powered during charging the battery
i have searched the TI Website and found the following products
(selected with the help of the http://focus.ti.com/en/download/aap/selectiontools/battery-chargers/tool.htm)
BQ24278 2.5A, Single-Input, Single Cell Switchmode Li-Ion BATTERY CHARGER with Power Path Management
BQ24253 2A Single Input I2C/Standalone Switch-Mode Li-Ion Battery Charger
i think the Power Path Management is the thing i need for the 'charge while power system' requirement
i need a charge current of 0.5A up to maximal 2A -
so i can charge the battery with 0.5C or 1C - depending on the recommendation of the battery datasheet.
(for the battery i will choose the biggest one that fits in my housing (max 2200mAh) -
and the size housing will be defined as a compromise between system uptime and as small as possible
after i know how much board-space i need for all the components ...)
Adjustable, 90% Efficient SEPIC Converter with 200-mA LDO for 1-Cell LiIon or Dual-Cell Applications
i think i can use the internal LDO to generate my 3.3V Output - so i have less parts.
i am new to powermanagment / Battery handling and would be glad to get some advice and tips
i am on the right way with this parts? or is there some other appnotes or helping documents that i have not found yet?
for this project the board-space is not limited in some way.
more it is use full if the parts are hand-solder able.
The Design - if the prototypes will work - will be mad as really small series for art projects-
so its most likely (up to now) they will all be hand-soldered.
if i have seen it right in the parametric search there is no chip with power path in TSSOP.
there is a micro controller in the system, so it would be possible to use a charger chip with I2C
but i would prefer a standalone solution.
thanks for your time and help