Bluetooth HC-05 not working

Hi,

I just got my bluetooth HC-05 module from ebay today. I soldered all the essential wires (Vcc,Gnd,LEDs,RX/TX) properly and connected it to a 3.3 volt supply. but when I switched on the power, nohing happened.

I checked and rechecked all the connections and everything was ok but neither the satus LED connected to pin 31 light up nor it was detected by my phone or computer bluetooth. I even soldered a wire on the pin 34 as stated in the datasheet ( http://cxem.net/arduino/download/HC%20Serial%20Bluetooth%20Products%20201104.pdf ) and connected it to gnd to see if it makes any difference but still the same result.

Also at first I was using 78L33 as a voltage regulator (my original supply was 5 volts) and later even tried  voltage divider circuit using a 10k ohm and 20k ohm resistor, in both cases voltage reading was exact 3.33 volts and voltage reading on both the LED pins (ie pin 31 and 32) is 0 volts.

Here is the exact circuit diagram that i have used (only difference was that i used a Atmega328 as the microcontroler)-  http://mbed.org/media/uploads/edodm85/ch05_sch2.png

 

is there any way i can check if the seller send me a damaged module or is the chip fried or am i doing something wrong?

Thank you!!!

it is working finally! i powered it with some weak AA alkaline batteries and the voltage reading was 3.9 volts

i read in the datasheet that it can work from 3 volts to 4.2 volts so 3.9 is still in the working range :slight_smile:

seems the problem was with current