Output level from serial LCD (CFA635-xxx-KL)

[tedmarshall]

We are using the serial version of the CFA635 in a new design and are using the logic-level interface (not using the RS232 converter board). I just discovered that the logic output from the module goes to +5V. This is a problem as the device we are connecting to the module (as are most modern SOCs with built-in UARTS) is not 5-volt tolerant. I understand that we will need to rev the design to include a level-converter on this line. However, for working with our prototype, is there any reasonable way to reduce the output level to <= +3.3V? (We can change surface-mount resistors.)

Also, your datasheet, CFA635TFEKL_v1.0.pdf, does not list logic output levels, only input levels. At a minimum, I'd suggest I'd suggest adding this.

You should also consider designing a new model which is more friendly to new designs.

Thank you.

Crystalfontz LCD Blog

Looking for additional LCD resources? Check out our LCD blog for the latest developments in LCD technology.

 

[tedmarshall]

Also, what is the maximum output current for the logic output? We need that for trying a simple voltage divider.

Thanks.

 

[CF Tech]

The KL versions just expose the UART pins of the microcontroller.

Here is the table from the microcontroller: