UART level translation, what type of translation IC is required?
December 1, 2009
I have two devices, and need to figure out how to translate between them for 2 wire UART.
U-Blox NEO-5G, 1.8V
Input low: 0.22V (MAX)
Input high: 0.91V (MIN)
Output low: 0.4V (MAX)
Output high: 1.4V (MIN)
Input low: 0 - 0.5V
Input high: 2.1 - 3.3V
Output low: 0 - 0.35V
Output high: 2.2 - 3.0V
UBlox -> Telit
LOW: .4V (MAX) -> 0-0.5V (WORKS)
HIGH: 1.4V (MIN) -> 2.1-3.3V (DOES NOT WORK)
Telit -> UBlox
LOW: 0-0.35V -> 0.22V (MAX) (DOES NOT WORK)
HIGH: 2.2-3.0V -> .91V (MIN) (WORKS)
So i obviously need a level converter of some sorts.
What type of converter is needed? CMOS? If so how do I select the voltages?