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I need to get 4 outputs from a 5V digital output as follows: 2 of them inverted and 2 of them non-inverted. I thought about using a 74 HCT 04 hex inverter in the following configuration:

schematic

simulate this circuit – Schematic created using CircuitLab

The 0 represents the output of an Arduino Digital GPIO pin and the output of the four inverters the outputs I'm going to use. Is this a valid configuration or am I going to run into problems whilst doing this? I am concerned because each inverter/buffer drives both another NOT gate and the actual output. The outputs I need to drive have a maximum low-level input current of -10 microA, and the the high-level input current 30-100 microA.

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  • \$\begingroup\$ What frequencies are you operating at? \$\endgroup\$ – vofa Jan 18 '18 at 21:21
  • \$\begingroup\$ There is no point to this configuration when the load is < 100uA. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jan 18 '18 at 21:38
  • \$\begingroup\$ What I should I use instead then? \$\endgroup\$ – andreas.vitikan Jan 18 '18 at 21:46
  • \$\begingroup\$ @vofa Less than say 50 Hz, it will switch max a few times per second. \$\endgroup\$ – andreas.vitikan Jan 18 '18 at 21:52
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For a drive current of 100 µA, you don't need multiple inverters. The Arduino can drive all the noninverted outputs directly, and a single inverter can drive all the inverted outputs.

If the signal is being generated by software and you've got an extra digital output on the Arduino, you could perform the inversion in software as well and drive the inverted outputs from a separate pin. Again, a couple hundred µA from one pin is not a big deal.

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  • \$\begingroup\$ The whole reason I thought about the inverter was because I was trying to save up on GPIO pins (need them for something else). But it's great that I can drive all the non-inverted ones from the pin and the inverted ones from a single inverter output. \$\endgroup\$ – andreas.vitikan Jan 18 '18 at 22:25
  • \$\begingroup\$ Could I also drive the gate of an N-channel MOSFET like a BS170 from the inverted output? Do I need a gate resistor, a resistor to ground? \$\endgroup\$ – andreas.vitikan Jan 19 '18 at 9:18

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