I want to use the 74LS244 as a bus transceiver but according to the datasheet, the maximum output current is 15 mA, while the maximum output flow back current is 24 mA.

What I think is that if I connect another output to the same data bus, the second one will pull the dataline down to low. Is there any way to connect multiple outputs to the bus?

I also want to ask if anyone knows how can I find the graph for input voltage vs input current of 74LSXX ICs since I'm designing circuits that have multiple inputs on the same line and I want to know if the output can provide enough current for them.

I know that I could find the input current in the datasheet but it only has the current rating for minimum and maximum voltage input.

  • 1
    \$\begingroup\$ The 74LS244 is a tristate device; the "G" control effectively isolates the outputs from the data bus. Systems commonly use this to ensure that only one device is driving the data bus at any time. \$\endgroup\$
    – henros
    Jan 15 at 9:32
  • \$\begingroup\$ @henros so which mean if the output enable go high (turn off), the output will be Isolated from the data line right? \$\endgroup\$ Jan 15 at 9:37
  • \$\begingroup\$ That’s what the datasheet tells us. As for loading, the datasheets used to have a U.l (unit loading) value that made the job a little easier regarding fan in/out. \$\endgroup\$
    – Kartman
    Jan 15 at 11:01

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