LK204-25 i2c voltage


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LK204-25 i2c voltage

Post by antonpiatek »

I've got a LD204-25 (might actually have one WV and one normal) which I'm looking to move from a pc over to a raspberry pi. It is currently powered by a modified serial cable and communicates over serial, but on the pi it would be easier to use i2c.
However hunting around suggests that as the display is 5v, the i2c will be 5v too, which would be a problem as the pi is all 3.3v.

Can someone confirm that the LK205-24 will need 5v i2c?

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Re: LK204-25 i2c voltage

Post by Clark »

Hi Anton,

I can confirm that your LK204-25 will operate at 5V. That unit uses an Atmel controller, which has a low range input tolerance of 0.6 x Vcc, or 3.0V on the I2C pins. During I2C transactions, devices typically only pull the lines low, they are pulled up by resistors you select to a voltage you set.

I would recommend you check that your Raspberry Pi is 5V tolerant, just to be safe. However, you should be able to connect the two devices using strong 3.3V pull-up resistors without any trouble.

Troy Clark
Design & Development
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