Hi team,
Why SN74LVC2G00 with Vcc=3V have two high level output current？
B.R.
Lucas
Hi Lucas,
Clemens is referring to the datasheet specifications here:
The recommended currents are provided as limits to maintain the appropriate output logic levels. As you can see in the above table, there are two rated output voltages for the 3-V supply condition, so there are two different recommended maximum currents in the recommended operating conditions table.
I agree that this is confusing, and we are moving away from this approach with newer datasheets.
Hi Lucas,
determined by the internal triode or mos
These are CMOS devices -- outputs are MOSFETs.
Will both currents may appear in the real use case?
To be clear - this is not a constant current output device. Both currents could appear depending on the loading. The output current is determined by the loading and the internal impedance of the device.
If, for example, the output were forced via a bench supply to be exactly 0.55V, then the maximum current would be 24mA, as per the datasheet description:
You can read more about the impedance of the device here:
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Here's an example circuit to show how loading affects current. With a 100 ohm load, the idealized output shows a current of 24mA.
Now, changing the load to 162.5 ohms, the current changes to 16mA.
In the more common case, the load is high impedance, shown as 1 Megohm below, and the current is very small - 3uA in this case.
