9.2.1.2 Detailed Design Procedure
To begin the design process, determine the following:
- Input voltage range
- The supply voltage of the upstream device (device that is driving input pin A) will determine the appropriate input voltage range. For a valid logic-high, the value must exceed the high-level input voltage (VIH) of the input port. For a valid logic low the value must be less than the low-level input voltage (VIL) of the input port.
- Output voltage range
- The supply voltage of the downstream device (device that output pin B is driving) will determine the appropriate output voltage range.