More on the UV-5R Charger

[Richard O'Neill]

"I traced out the schematic of the battery charger and put it in the Files
section, titled UV-5R Charger.pdf Also on the schematic page are some
voltage readings. I was inspired to do this after reading on Battery
University
http://batteryuniversity.com/learn/article/lithium_based_batteries
that some chargers go into a constant trickle charge at the end of the
cycle which is bad for Li batteries. I was glad to find that the charge
current goes to 0 when the light goes from red to green on the charger
which came with my UV-5R.

The SC-6038 IC manufacturers website says the IC has an input of 9-18V,
output 8.4V, however I think I saw somewhere the Baofeng charger has a
max input of 10.4V. This would be because the IC would need a considerable
heatsink to drop the voltage from 18 V to 8.4V at 375 mA battery charging
current. It would be a neat hack to add a voltage regulator inside the
charger base to drop 14.7V from a car electrical system to 10V for the
charger."

John
KK6IL

https://groups.yahoo.com/neo/groups/baofeng_uv5r/conversations/topics/8285

https://groups.yahoo.com/neo/groups/baofeng_uv5r/conversations/topics/13126