HC05 Bluetooth Module Voltage Divider

Introduction: HC05 Bluetooth Module Voltage Divider

Recently I borrowed a Bluetooth module from my friend, because I had misplaced mine. I noticed that the Bluetooth module had no breakout board. So I read though the data sheets and found that this was a HC05 and it ran on 3.3v logic. But the Arduino TX pin runs on 5v signal, so all you needed to do is build a breakout board for it here is how you do that.

So lets get started...

Step 1: Tools and Components

So you will be needing a

Soldering skills are required for this instructable, you can learn to solder via a wide rang of tutorials on YouTube.

Step 2: Circuit

The circuit is quite simple all you have to do is create a voltage divider using a resistor combination the required output is 3.3v. Assemble he circuit on a pref-board. Try out some test sketches in the examples section of the Arduino IDE to make sure you got it working.

Step 3: Finishing

Do not worry about the messy resistors on my board. Some of it are to power on the led and some of it is to run terminal commands. You may rarely need to use those and if you do you can PM me and I will mail you the circuit on how to do that.

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    Question 4 years ago on Introduction

    how did you calculate the values of the resistances to reduce the voltage from 5 volts to 3.3 volts? I understand how to calculate using the voltage divider principle from circuits but it requires you know the resistance of the blue tooth module and the resistance of the resistor you want to use. Where can I find the data sheet for the bluetooth module you used? Difficult to find on google.


    Answer 4 years ago

    he made one using the little board. order an hc05 or hc06 they are the same thing. the resistors you can google for the values. i myself use 110 ohms for R1 and 220 for R2 which will give you 3.33333333 when you do this (220/(220+110)x5 = 3.33333333333. all you have to remember is that R1 is 1/2 of R2.

    najeeb en
    najeeb en

    6 years ago

    Mail me the full diagram.