Chillout Zone
Let's Make Robots!
Home » Forums » The 4 elements » Electronics

Components to put bw 3.3v signal and 5v

, , ,
Forum topic
By Mickey

March 10, 2010
Mickey's picture

I have an Arm based platform with Serial UART interface but in 3.3v level.

I want it to communicate with my Arduino.

I have a 3.3v power source in the Arduino(Dumilinove).

My question is what components to put between the 3.3v platform RX/TX and the Arduino RX/TX ?

‹ Servo Position Feedback ? How do I filter audio? ›

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
By OddBot
@ Wed, 2010-03-10 11:31
OddBot's picture

I had the same problem interfacing Mr. Tidy (5V) with an Xbee module (3.3V). Here is the Schematic I posted then.

Xbee_interface_Schematic.jpg

In your case you can leave out the 3 diodes, 3K3 resistor and 10uF capacitor I used to create a 3.2V supply.

By RobotFreak
@ Wed, 2010-03-10 13:59
RobotFreak's picture
The schematic above will work with a PICAXE, but not with an Arduino. The PICAXE use inverted signals for RX/TX. You will need a second transistor stage on each side to inverted the signal once more for the ARM/Arduino. Or you can use the simpler sparkfun level converter schematic.
By OddBot
@ Wed, 2010-03-10 14:35
OddBot's picture
Good point, I forgot I had to invert the signal for Picaxe.