Mixing CMOS and TTL - Electronic Circuits Projects Diagrams Free

What · 3rd January 2008, 07:09 PM

Is it possible to Drive a 74LS47 with a 4029? I noticed in the data sheet for the 4029 it said;

"Low power TTL compatibility: fan out of 2 driving 74L
or 1 driving 74LS"

Does that mean as long as the supply voltage is in the range for TTL, the 4029 will be able to output to the 7447?

Also if I use an LM317 to regulate voltage from a constant 12V power supply. Then run the circuit in my car, where the supply voltage will be between 11 - 15V Will the regulated output of the LM317 change as the input voltage does? If so what can I do to have a regulated 5 V supply in my car.

ericgibbs · 3rd January 2008, 07:33 PM

Quote:

Originally Posted by What

Is it possible to Drive a 74LS47 with a 4029? I noticed in the data sheet for the 4029 it said;

"Low power TTL compatibility: fan out of 2 driving 74L
or 1 driving 74LS"

Does that mean as long as the supply voltage is in the range for TTL, the 4029 will be able to output to the 7447?
Yes, use a +5V supply line.
Also if I use an LM317 to regulate voltage from a constant 12V power supply. Then run the circuit in my car, where the supply voltage will be between 11 - 15V Will the regulated output of the LM317 change as the input voltage does? If so what can I do to have a regulated 5 V supply in my car
If the LM317 is set to give +5Vout, then it should give +5Vout for an input range from about +8V thru 24V
.

Does this help?

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3rd January 2008, 07:09 PM	(permalink)
What	Mixing CMOS and TTL Is it possible to Drive a 74LS47 with a 4029? I noticed in the data sheet for the 4029 it said; "Low power TTL compatibility: fan out of 2 driving 74L or 1 driving 74LS" Does that mean as long as the supply voltage is in the range for TTL, the 4029 will be able to output to the 7447? Also if I use an LM317 to regulate voltage from a constant 12V power supply. Then run the circuit in my car, where the supply voltage will be between 11 - 15V Will the regulated output of the LM317 change as the input voltage does? If so what can I do to have a regulated 5 V supply in my car.