I am planning on using the SN74CBTD3384 in my design to interface 5Vdc input commands to a 3.3Vdc CPLD. There are a few questions I have that I cannot figure out a solid answer from the data sheet.
1) When both Enables are active, what is the normal and max current used off the Vcc? I see the data sheet says "Continuous channel current" says 128Ma, but I assume that is the current through an A-to-B bath maximum. Is it figured out using the delta Icc number? With the test condition presented (and with VCC at 5Vdc), does this mean that at every input where we expect data to flow, we add 2.5mA, so the total for the chip could be as high as 25mA with both enables active and all channels held at 5Vdc? I am working power budget right now and interpreting this data sheet is my only hold up.
2) From what I can see, this is a bidirectional chip, which is what I am looking for. I can see that putting 5Vdc on the A input will give a 3.3Vdc on the B output. What happens to the 3.3Vdc signal @A when B is the input channel and A the output? is it held at 3.3, or does this level change as well?
Thank you for your help,
Matt
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