74ls04

[moonstreat]

hello, I know if I can connect a 12V signal at the entrance of a 74ls04.

 

[edeca]

http://www.datasheetcatalog.org/datasheets/70/375318_DS.pdf suggests not. 7v max input (and not recommended either).

 

[moonstreat]

I called the sign of an inductive sensor, I have my sensor connected to 12V, when the sensor is activated, the signal is 12V, NPN is a sensor, I connect to this signal to 74ls04 in 5V PNP output have, and would my problem solved.

 

[ericgibbs]

I called the sign of an inductive sensor, I have my sensor connected to 12V, when the sensor is activated, the signal is 12V, NPN is a sensor, I connect to this signal to 74ls04 in 5V PNP output have, and would my problem solved.

HI,
Dont connect a 12V signal directly into a 74LS IC.
Use a simple voltage divider from 12V to step it down to +5V, make sure when the output of the sensor is zero [0v] the lower value of the divider resistor is low enough to pull the 74LS input to a logic 0, say less than +0.5V.

 

[moonstreat]

You can post a voltage divider for my project?

 

[ericgibbs]

You can post a voltage divider for my project?

hi,
Try this,
I am assuming your sensor can source [ supply ] into the 1K and 470R a current of 8mA.???
If not let me know.

 

[moonstreat]

I l'adresse! say something already

 

[ericgibbs]

I l'adresse! say something already

Hi,
Are you asking me a question.????

 

[moonstreat]

not! I'll test your circuit .. I'm not English, so I have to translate by google translate, and sometimes the translations go wrong .. : \

 

[moonstreat]

I always have 12 V at the output of the voltage divider, with the inductive active and deactivated! Why? : S

 

[moonstreat]

**broken link removed**

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[ericgibbs]

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hi,
What supply voltage do you have connected to pin14 of the 74LS04.???