Interfacing Xbee (3.3v) with MCU (5v)

[daren208]

hi, I have a question regarding how to interface between Xbee (3.3v) with my MCU (5v).
It is just add a resistor between DI & D0 of Xbee and TX and RX of MCU ?
Or using diode or any else component ?
Pls help me, actually i want bought the started kit but it sold out dy. So I just bought RF module.
Thanks...

[shahrul]

I think, you can use transistor switch to convert 3.3V signal into 5V signal and the opposite convert.

[shiyan]

From 5V to 3.3V is little bit easy, use resistor ladder as voltage divider. 2.2K and 4.7K should be nice to be the divider.

Or you can try zener diode too... 3.3V zener.

AS for 3.3V to 5V.... ehmmmmm a bit complex. Maybe you can directly try first, hoping the 3.3V is high enough for the 5V microcontroller to detect as logic high

[daren208]

Thanks>
So mean just use transistor to 3.3 to 5 and 5 to 3.3 v is work for UART pin ? Actually I found few way to convert between 3.3 to 5 V. What i worry is this is data communication pin. scare after simply use transistor convert will affect the data. If normal I/O should be no problem...

[shiyan]

transistor method can apply for both way, but it requires more soldering and components. While resister network or ladder or divider can only apply from higher voltage to lower voltage.

[daren208]

okay thanks. Then I use transistor la