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What's the difference between the CD4009 and CD4069?

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Hero999

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I've read through the datasheets and I'm ashamed to say I'm stuck. One of the problems is that I can't find two datasheets from the same manufacturer and different manufacturers are going to vary somewhat.

I already have loads of CD4009s in my junk box, I'm just wondering if it's worth buying some CD4069s as well.
 

dknguyen

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THey have different power supply schemes and the output circuitry is different. 4009 also has noticeably higher output drive current.
 

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Hero999

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4009 also has noticeably higher output drive current.
Interesting, I thought the higher numbers were supposed to be better?

As the output current is higher does that mean I can't use the CD4009 as a linear amplifier?

EDIT:
I also couldn't find any referance to the gain on either of the datasheets, is there a difference?
 
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RadioRon

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The CD4069 parts that are for sale these days always have a U after the number, that is CD4069U and this is important. This indicates that it is an UNBUFFERED gate/inverter, which is different than the CD4009. Here is a link that explains the difference:

http://www.electro-tech-online.com/custompdfs/2009/08/scha004.pdf

It is possible to buy "U" versions of 4009's and other logic parts as well, but they would be marked as 4009U in that case, and then I don't think there would be much difference with a 4069U in that case.

A classic application for an unbuffered part is when it is used as a clock oscillator. In this case the shorter propagation delay through the part, and slightly less complex transfer function means it oscillates at higher frequency and more reliably.
 

unclejed613

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very seldom will you find the gain or the linear portion of the transfer curve mentioned in a CMOS inverter data sheet, just because they're "logic" devices, and the linear portion of the transfer curve is something of an "undocumented feature".
 

Hero999

Banned
The CD4069 parts that are for sale these days always have a U after the number, that is CD4069U and this is important. This indicates that it is an UNBUFFERED gate/inverter, which is different than the CD4009. Here is a link that explains the difference:

http://www.electro-tech-online.com/custompdfs/2009/08/scha004-1.pdf

It is possible to buy "U" versions of 4009's and other logic parts as well, but they would be marked as 4009U in that case, and then I don't think there would be much difference with a 4069U in that case.

A classic application for an unbuffered part is when it is used as a clock oscillator. In this case the shorter propagation delay through the part, and slightly less complex transfer function means it oscillates at higher frequency and more reliably.
Thanks, I dodn't know that.

The ones I have are UBs so maybe I should buy some Bs.
 
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audioguru

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The CD4009 is not recommended by Texas Instruments. The CD4049 is recommended instead if it has a single supply voltage.
Both [/quote] are not symmetrical. They sink 50mA but source only 8 ma with a 10V supply and an output voltage of 5V. If they are used as a linear amplifier then they self-bias at an output voltage too low and with low gain. They also might melt.

These and the CD4069 are logic inverters that are always Un-Buffered. The CD4069 has symmetrical source and sink currents but not as high as 50mA. It works well as a linear amplifier.

Here is a graph of the gain and frequency response of a CD4069 (or a 74C04) Cmos inverting amplifier:
 

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Hero999

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Where did you get that graph from?

It's not on the datasheet.
 

audioguru

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Where did you get that graph from?

It's not on the datasheet.
I got the graph from RCA in the 60's.
RCA Semi got bought by Harris.
Harris got bought by Intersil.
Parts of Intersil got bought by Maxim.
I don't know who will buy Maxim.
 

Hero999

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It looks like I'll have to order some CD4069s or 74C04s then.
 

audioguru

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A Cmos inverter makes a pretty distorted output because its output compesses the signal near the rail voltages.
 

Hero999

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That shouldn't be a problem at low gains, due to negative feedback.

Not going to near either rail should also help.
 

audioguru

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I made some fairly low distortion (0.02%) sinewave oscillators with the inverter from a CD4069 used as a compressing linear amplifier to fix the amplitude. It was fed the signal from a switched-capacitor lowpass filter IC and both were together in a feedback loop. The lowpass filter reduced the 3rd harmonic distortion caused by the compression.
 
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