Communication between 3.3V USART system with a 1.8V USART system

[long88]

Hi all,

I am using a microcontroller (PIC18F46k20) and intend to communicate with a GSM module.
The USART system of the GSM module was 1.8V. May i use a voltage divider to step 3.3v down to 1.8 V in order to allow communication between 3.3 USART and 1.8V USART?
My concern is whether MCU recognize voltage 1.8V signal from GSM module as high logic.

Thank you very much.

- - - Updated - - -

what is the USART threshold voltage level for PIC 18F46K20 ?

 

[Soumyajit]

Which GSM module are you using, usually all GSM modules have UART working at 2.9 to 3.1 volts...

 

[YEAR_]

You need voltage converters on both Rx and Tx, you can use simple Transistor based circuit. some GSM manufacturers provide reference circuits.

 

[dilraj.n]

You can use the following level converters for your application
https://www.sparkfun.com/products/11978

 

[Realy]

i think that sometimes The GSM module is compatible with 3.3V,so you can try do it ....

 

[zivoradbre]

Perfect solution for you problem TXS0108: **broken link removed**