M66_i2c_hardware

IoT Modules GSM Module
1

Hi
i use m66 and I want to use i2c for seg lcd at 3.3 Vcc, what method should I use for hardware connection?
voltage divider,level shifter,or just pull up res for sck and sda …
I prefer not to use level shifter
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2

Hi Amir ,

Best Approach would be having 3V supply to your I2C IC and connect I2C lines with current limiting 1K resistor and pulling line upto VDD_EXT .

If you cant follow it then I think you will need level shifting .

Transistorised level shifting is better approach .

Thank you
Ratan

3

Hi Ratan
Thank for your reply, do you have any suggested level shifter for 3.3 to 3 volt?
And can i use a voltage divider??5.6k in pull down and 1k…
Thank you.

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4

Hi amir ,

Actually many of clients have worked with 3.3V direct .
I suggest you to use 3V supply for peripheral device that would be best . you can use some voltage drop diode for supplying your I2C IC .

Please do use series resistor for current limiting if you are directly communicating .

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