scaling logic signal voltage

hey list,

so i'd like to use the digital pins of my arduino to switch audio signals on/off using a CMOS4066 chip.

the cmos is powered with -5v and +5v to handle dual ended audio signals - but in order to open/close the CMOS gates i need to pull the control pins from +5v down to -5v.

any idea how i can convert the arduino 0-5v logic signal to something like -5 to +5 ?

thanks! ú

but in order to open/close the CMOS gates i need to pull the control pins from +5v down to -5v.

You 100% sure of that? Have another read of the data sheet.

the way i understand it, it says control LOW voltage should be equal to VSS?

am i wrong?

im very happy if im wrong and my arduino will do the job with no frills!

I know how to find a datasheet on the web. Do you ? Would you like some help ? How about it ?

so my question doesnt make sense - i apologize.

but i dont see how me misunderstanding a datasheet and asking a question as a result makes me a lazy person.

i am inexperienced, and the title of this thread obviously implies misinterpreted some information i read. but thats what this forum is for - asking questions. right?

I never said you misunderstood anything. You are asking us to make informed decisions without the datasheet. My question was intended to imply that since YOU are the person asking for answers, you should be the person posting the datasheet. It has nothing to do with whether you are experienced or not , UNLESS you THINK that because WE are experienced that WE have MEMORIZED the datasheet for EVERY IC EVER MADE. (maybe we have , but that is beside the point) . When you have read page 5 of the datasheet for the ic that you want to use AND posted it as an attachment using the "Additional Options " button below, we would be happy to help you. First you have to do your DUE DILIGENCE.

When you have done that , maybe you can tell me what is wrong with this statement:

but in order to open/close the CMOS gates i need to pull the control pins from +5v down to -5v.

Because I am such a nice guy I will give you a clue, Look for the words: "BIDIRECTIONAL SIGNAL TRANSMISSION VIA DIGITAL CONTROL LOGIC" Don't come back until you can answer that question. .

I think you are being a bit hard on this guy. He asked a perfectly reasionable question. Most analogue switches I have seen need a 0 to 5V control voltage requirement. If not you are better basing the audio signal to 2.5V with two resistors and a capacitor.

Your right , most do. Why am I being hard on him for expecting him to post the datasheet ? If he had done that I would have told him why his conclusion is wrong. Am I being hard on him for expecting him to google the chip number and post the sheet to make it easier for us to show him what page has the information he needs to know ? I don't think that is asking too much.

OK, so the datasheet (page 11) suggests that you do in fact, have to drive the control inputs from rail to rail, but if you want to control it with 0 to 5V logic and have a split ±5V supply, you preface it with a 4054 level shifter.

Page 5 shows the control voltage as 0 to 5V. It’s quite clear in the
BIDIRECTIONAL SIGNAL TRANSMISSION VIA DIGITAL CONTROL SIGNALS box.

ic-cmos-4066 (1).pdf (266 KB)

raschemmel: Page 5 shows the control voltage as 0 to 5V. It's quite clear in the BIDIRECTIONAL SIGNAL TRANSMISSION VIA DIGITAL CONTROL SIGNALS box.

Yep, sure is clear. :D

See that vertical rectangular box toward the left of the diagram which says "HCC-HCF 4054B" ?

Know what that is?

See the waveform between that box and the HCC-HCF 4066B? What does it say?

raschemmel: When you have read page 5 of the datasheet for the ic that you want to use AND posted it as an attachment using the "Additional Options " button below, we would be happy to help you. First you have to do your DUE DILIGENCE.

When you have done that , maybe you can tell me what is wrong with this statement:

but in order to open/close the CMOS gates i need to pull the control pins from +5v down to -5v.

Because I am such a nice guy I will give you a clue, Look for the words: "BIDIRECTIONAL SIGNAL TRANSMISSION VIA DIGITAL CONTROL LOGIC" Don't come back until you can answer that question.

Q.E.D.

I think you just answered the OP’s question. (You are correct, I missed that. My bad… I stand corrected).
My clue was still good… XD

Because I am such a nice guy I will give you a clue,
Look for the words:
“BIDIRECTIONAL SIGNAL TRANSMISSION VIA DIGITAL CONTROL LOGIC”

See attached for TWO options:
OPTION-1
HCC-4054 (shown in the datasheet for the HCC-4066 where I mentioned. and where Paul__B pointed out that I missed …
OPTION-2
ADG-511;; Logic level (0-5v) controlled analog switch.

ADG511_512_513[1].pdf (141 KB)

HCC-4054.pdf (339 KB)

Q.E.D.

@Paul__B, There are so many uses of the term I am not sure which one you meant. did you mean "which remains to be demonstrated.." ? http://en.wikipedia.org/wiki/Q.E.D.

raschemmel:

Q.E.D.

@Paul__B, There are so many uses of the term I am not sure which one you meant. did you mean "which remains to be demonstrated.." ? http://en.wikipedia.org/wiki/Q.E.D.

No not quite:- quod erat demonstrandum It IS demonstrated.

Thanks Mike

Back on topic. The 74HC4051; 74HCT4051 will handle +/- 5V signals but only need 0 - 5V logic to drive it.

thank you. this has been very insightful... i will opt for using the 74HCT4051! it's exactly what i need.

arschemmel, i apologize and will remember to post the datasheet next time. 8)