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Connecting output of TL074 to CMOS logic input

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danjel

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If I connect the output of a TL074 to a CMOS logic input (e.g. a logic gate) do I need anything in between?

e.g. pulldown resistor?
current limiting?
 

ericgibbs

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Most Helpful Member
If I connect the output of a TL074 to a CMOS logic input (e.g. a logic gate) do I need anything in between?

e.g. pulldown resistor?
current limiting?
hi Dan,
What are the 074 supply rails and how is it configured.??
 

danjel

Member
There would be a single supply of +12V so the output could only swing between 0 and 12.

I know that you usually need a pullup/pulldown resistor with CMOS for draining capacitance at input and to keep pins from floating.

In the case of using an opamp like a TL074 connected directly to it do you still need to do this or can the CMOS inputs discharge via the Op Amp?

Same question for using an LM358 as well.
 
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ericgibbs

Well-Known Member
Most Helpful Member
There would be a single supply of +12V so the output could only swing between 0 and 12.

I know that you usually need a pullup/pulldown resistor with CMOS for draining capacitance at input and to keep pins from floating.

In the case of using an opamp like a TL074 connected directly to it do you still need to do this or can the CMOS inputs discharge via the Op Amp?

Same question for using an LM358 as well.
hi,
At 12v rail supply,I would use a 10k pull up for both types of op amp.
 

crutschow

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Is the CMOS logic operating from the same supply as the TL074?
 

danjel

Member
yeah both from 12V.

I have a jack for externally plugging in signals and then this is fed to the op amp (act as a buffer or comparator) and then the output goes to CMOS logic input.

both devices powered from 12V.
 
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