Charging 3.7 lipo Battery and using it the same time.

ArakelTheDragon

Joined Nov 18, 2016
1,353
The current from the zener is only enough for the zener to work. Its in the datasheet. The diode will need a certain amount of current to keep the voltage stable.

The current from the transistor will come from up. The resistor for the current from the transistor. Keep in mind Kirhov;s law, all currents in must be equal to all currents out. Meaning you will get from the 100Ohm in my circuit enough for the zener, but everything else for the transistor has to come from up. After which there will be amplification by the transistor and this will be the current applyed on the load.
 

jayanthd

Joined Jul 4, 2015
944
The current from the zener is only enough for the zener to work. Its in the datasheet. The diode will need a certain amount of current to keep the voltage stable.

The current from the transistor will come from up. The resistor for the current from the transistor. Keep in mind Kirhov;s law, all currents in must be equal to all currents out. Meaning you will get from the 100Ohm in my circuit enough for the zener, but everything else for the transistor has to come from up. After which there will be amplification by the transistor and this will be the current applyed on the load.
Ok. I will check the circuit tonight but why not use a specific regulator and charger IC deviced specifically for battery operated device which consume very less power ?


https://www.quora.com/What-are-the-current-requirements-for-ESP8266-01

https://openhomeautomation.net/esp8266-battery/
 
Last edited:

Thread Starter

Dumken

Joined Oct 7, 2014
31
Thank you guys. The information has been helpful. But a parallel connection of the battery, load(esp8266) and charger is it correct?
 

jayanthd

Joined Jul 4, 2015
944
Thank you guys. The information has been helpful. But a parallel connection of the battery, load(esp8266) and charger is it correct?
Yes, Charger output will be in parallel to battery. Voltage is always applied in parallel to power pins.

First comes charger then battery in parallel to charger. Then comes 3.3V regulator in series with V+ of battery and then comes ESP8266 across V+ and GND.
 

Thread Starter

Dumken

Joined Oct 7, 2014
31
Yes, Charger output will be in parallel to battery. Voltage is always applied in parallel to power pins.

First comes charger then battery in parallel to charger. Then comes 3.3V regulator in series with V+ of battery and then comes ESP8266 across V+ and GND.
So what it means is that the battery is also being discharged with the esp8266 or is the supply voltage coming from the charger?
My reason for asking this question is that i noticed that the esp8266 works well on battery till i switch on the charger. The esp8266 starts to misbehave(endlessly reloading the web address page)
 

jayanthd

Joined Jul 4, 2015
944
So what it means is that the battery is also being discharged with the esp8266 or is the supply voltage coming from the charger?
My reason for asking this question is that i noticed that the esp8266 works well on battery till i switch on the charger. The esp8266 starts to misbehave(endlessly reloading the web address page)
If the charger is On all the time then battery will be getting charged and not discharged. Regulator will be getting power directly from charger and providing 3.3V output.

When Charger is not On then battery will provide whatever its voltage to regulator but if regulator gets sufficient voltage as mentioned in regulator datasheet it will provide constant 3.3V output.
 
Top