What's the difference between the CD4009 and CD4069?

[Hero999]

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]

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

 

[Mike_2545]

Is the answer 60?

 

[Hero999]

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?

 

[RadioRon]

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:

https://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.

 

[BrownOut]

That app note was a great read! Keep linking good, informative sources.

 

[unclejed613]

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]

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:

https://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.

 

[audioguru]

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:

 

[Hero999]

Where did you get that graph from?

It's not on the datasheet.

 

[audioguru]

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]

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

 

[audioguru]

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

 

[Hero999]

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

Not going to near either rail should also help.

 

[audioguru]

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.