HC 05 With 2-3v lithium cell
How to Power HC 05 using 2 -3.3 v lithium cell battery.
Hc05 is not working when I connect it with the 2-3.3v cell battery.
I have checked the total voltage .,=6.68v
But Hc 05 is not responding.
So I read the data sheet of hc05 ,in that it says that the operating voltage of hc05 is between 3.3v. To 6v .
I gived the voltage above 6v .
So I decided to connect a 2v led series to hc05 then the Hc 05 will get voltage near 4.3 or grater.
I didn't checked it practicaly .
If you know Any thing about that please help me.
@Geethesh As you told HC-05 will surely work with 3.3V Li-ion battery, I am already using my hc-05 with 3.3v battery so I can assure you that. But you also told that you have given a power of above 5V to the HC-05 i.e around 6.6V which means you have already fried the chipset of HC-05. The IC's of HC-05 are mostly only 3.3V-5V tolerant which means they get easily damaged if you plug in higher voltages.
And it is not so advisable to use LED's in series to step down the voltage. Better use a voltage regulation IC to bring down the voltage.
@kowshik1729 I wish to use led in series because I want the all circuit so small .
To make a key finder device .
My hc05 didn't burn out it was working when I connected it to arduino 5v after that.
@Geethesh Nice. So if you want to limit the voltage instead of using an led in series use a resistor. It's a great alternative because resistor can easily tolerate little amounts of current surges and can make the voltage drop a little bit. So try using it..!!
Geethesh last edited by Geethesh
@kowshik1729 I just find that hc05 is not getting much ampere(current) from that battery.
That is the main problem .
What to do
Can you share me any specifications and picture of the battery??
@Geethesh I've seen your battery specifications. The battery you are using gives out 3V which is a nominal voltage but you must take one more parameter into consideration while choosing a battery for your applications. It is nothing but Amperage that it can supply.
I will explain "WHY?" ampere rating is so important in your application. HC-05 module draws most of the power from the battery while transmitting the packet data, it almost draws 200mA of current at a voltage of 3.3V this means the battery you are going to use must supply current at this amounts. But if we see the battery that you have to use i.e CR2032 which is a coin cell battery, its maximum supply current is just 3mA but our minimum required supply current is 200-250mA which is way too high for the battery to supply and that is the reason of your failure.
So, please use these battery types of Li-Ion batteries which can give a high supply current of order 500-700mA at 3.7V. I've been thinking that you are using these since the start of our conversation and that lead to my misunderstanding and made the correct reply late. Sorry for the delay. All the best...!!
@kowshik1729 thank you
@rafitc99 I changed the buffer and that solved the problem. Thanks a lot for coming to my rescue.
@salmanfaris I did change the buffer size and everything is working perfectly. Thanks coming to my rescue.
I am using the hardware serial (pin 0 and 1 on Arduino Uno)
As @rafitc99 mentioned, you need to expand the Serila buffer, in the hardware serial also the Arduino board package implements a 64-byte ring buffer for send and receive on the hardware serial messages. So you need to change that to 256 as per your message length.
@rafitc99 The thing is that I am not using the SoftwareSerial library in receiving the message from the first microcontroller. I am using the hardware serial (pin 0 and 1 on Arduino Uno)