Using a TTL buffer.
It makes sense to use CMOS logic in your buffer designs wherever
possible. You should also make it clear in the design
documentation that CMOS logic is to be used.
Example: Buffering three LEDs with a 74HC04
This example shows a 74HC04 buffering three LEDs. As discussed
in Solution, we do not require pull-up resistors with the HC
(CMOS) buffers.
In this case, we assume that the LEDs are to be driven at 15 mA
each, which is within the capabilities (50 mA total) of the buffer.
