I have a device that operates with 3.2 V MAX, and I wish to power it from a standard 3.7 Li-Ion battery. A fully charged battery=4.2V.
I used a simple LM317 circuit to drop voltage to 3.2V and it worked perfectly.
Now the problem is as the battery starts to drain, the output voltage starts to become lower, so subsequently the LM317 output voltage will be lower as well, for example
- batt=3.7V, LM317=2.5V
In which this case the voltage is not enough to keep the device up and running.
So what I need is some sort of dynamic regulator to keep the output voltage fixed at 3.2V until the battery voltage drop to 3.2V as well. Advice on good ways to achieve this would be appreciated.