Home made audio multiplexer (switch) using 4051 or 4052? (74HC...)???

[Rahuleverg]

You Quoted:-
" I used HEF405X Series analog multiplexer/demultiplexers in several applications...

HEF 405X series gives 5 nano seconds propogation delay and % 0,04 distortion under 10V supply voltage.Please be realistic... Hi-Fi systems are gives us about %0.1 distortion.Be easy and use these products.

You are talking about relays for signal switching.What about RFI and EMI conditions generated by relay coil ?? .This gives a chattering on sound while switching i think..

Take a look at these links:

Detailed Datasheet (Philips)
http://ics.nxp.com/products/hef/datasheet/hef4052b.pdf

Some applications
Audio Switch Notes
MOSFET Integrated Amplifier"

I want to know can these 405X Series can Control analog singnals of 18V P-p that is VEE=-9V and VDD=9V with Digital Control Signals of 5V? Is there any way out? Please do reply at the earliest. Thanking you in advance.

[danzup]

Originally Posted by ozangazi

I used HEF405X Series analog multiplexer/demultiplexers in several applications...

HEF 405X series gives 5 nano seconds propogation delay and % 0,04 distortion under 10V supply voltage.Please be realistic... Hi-Fi systems are gives us about %0.1 distortion.Be easy and use these products.

You are talking about relays for signal switching.What about RFI and EMI conditions generated by relay coil ?? .This gives a chattering on sound while switching i think..

Take a look at these links:

Detailed Datasheet (Philips)
http://ics.nxp.com/products/hef/datasheet/hef4052b.pdf

Some applications
Audio Switch Notes
MOSFET Integrated Amplifier

What EMI what RFI ??
When i select an input , that is : the relay is on and nothing more come from , as from basic physics we know that !
And about a simple Ag contact what distortion introduce in audio path ???

[Mooly]

Originally Posted by Rahuleverg

I want to know can these 405X Series can Control analog singnals of 18V P-p that is VEE=-9V and VDD=9V with Digital Control Signals of 5V? Is there any way out? Please do reply at the earliest. Thanking you in advance.

Yes... use a level shift arrangement using perhaps a small signal FET ( eg 2n7000) The logic runs on 0 and 5 volt, so assuming 0 is the same as audio ground use the FET and high value resistor across the -/+9 vdc and use a high value resistive level shift divider from the logic to the gate of FET.

Or run the logic referenced to -9 volts... loads of possibilities.

[ozangazi]

Yes it's possible.Please look at this sch.

http://www.sydzdiy.com/uploads/allim...040492I4-0.jpg

[Rahuleverg]

Respected Sir,
Thank you for the help but still one confusion, in the pic A, B are controlled by 6 - 12V Logic levels, right? Can the chip series be operated at +12 to -12V and controlled by 5V Logic Levels? Will there be no problem? Then why it is not mentioned in the datasheet? Rather it is written Logic 1 is equal to VDD? Thanking in advance for your help.

[DougieFresh1970]

Originally Posted by pekinin

I am interested in building a audio inputs switch (audio selector). I have experience in digital circuits, but not much in analog circuits, but I am passionate about audio. So I need a little help.

Had thought of using a pair of 4051 with 8 inputs each, and also a small micro controller (atmel avr or microchip pic). It would be better to use the 4052? (I prefer to have 8 stereo inputs with two 4051, one for each channel)

Someone can recommend me any design or schematic?

I have to put a "audio buffer" or preamp? in the output? in the input? in two places? (if so, could use a NE5532?)

Any information is welcome: schematics, designs, tips, ideas... (I need help especially in the analog audio part (input or output preamplifier, buffer...)

Thanks you very much for everything!

PS: The 4051 has an acceptable quality? or make noise in the audio?

Thanks! bye!

Here is a sample 4052 used as a tape/cd interface circuit for AC DELCO car stereo.