Hi TI Team and Design Gurus,
I am working on a system that require an in-system 4 series NiMH battery charger with at least 500mA charging current. This is a high volume, cost sensitive application and PCB area available is quite limited.
The required design need to cover quite a wide input voltage range, from 4.5V to 20V (ideally up to 35V) hence the charger need to be a buck-boost type.
I can think of following design options
1. Buck Boost Battery charger, e.g. BQ25792. This is some other buck-boost chargers are specified as a multichemistry battery charger but I am unable to find any detail for charging NiMH. Can someone point me to any application notes using BQ25792 or any other similar charger IC with NiMH battery charging detail.
2. Boost regulator followed by Linear Battery charger but due to high charging current requirement (500mA) the linear charger (e.g. BQ25171-Q1) have to dissipate over 1watt hence temperature rise of over 70C above ambient. Is it going to a viable solutions?
3. Boost regulator followed by buck Battery charger but this will require multiple inductor hence higher PCB area and cost. could you please suggest
Any suggestions, design ideas are welcome
Thanks in advance
M Mujahid
