Acqiris SA230E User Manual page 68

5.4 Multi-purpose inputs and outputs
Figure 5.3 - Programmable IO schematic
As an Output
The high level output will typically give 1.6 V into 50 Ω. As can be seen in the diagram below, the 3.3 V
output buffer has a 50 Ω resistor in series. Therefore the available output high level voltage will depend
on the load applied. In the example below a 50 Ω termination will result in a nominal high level of 1.6 V.
(Vo = (Rload/(50 + Rload)) * 3.3).
Figure 5.4 - Output equivalent circuit.
68 Acqiris SA230E User's Manual