[sdiy] Using the VEE pin on a 405x Multiplexer

[Justin Owen]

-----Original Message-----
From: David G. Dixon [dixon at interchange.ubc.ca]
Received: 08.10.2010 16:55:55
To: 'Justin Owen'; 'SDIY List'
Subject: RE: [sdiy] Using the VEE pin on a 405x Multiplexer

>> I'm trying to understand how to use VEE (Pin 7) on a 4053 Multiplexer.

>> My understanding is that I can apply a negative voltage bias to this pin
>> which will allow an AC signal to pass through (I'm hoping for approx. 10V
>> PP @ +/-5V) - all while powering it with +12V @ VDD Pin 16.

>> Can anyone confirm a) if this understanding is right, b) what the maximum
>> negative voltage is (is -12V OK?) that I can apply to VEE and c) is it
>> just one in, one out or is there some equation balance between VDD & VEE.

> The CD405x datasheet says it can handle signals up to 15Vp-p, and mentions
> specifically that VDD = 5V and VEE = -5V allows +/-5V signals to pass.
> However, under the Absolute Maximum Ratings section, it says the minimum
> input voltage is 0.5VDC.  These statements would appear to be mutually
> exclusive!

Well, I got bored and impatient so I plugged VDD: +12V, VSS: 0V and VEE: -12V and I'm now running an 11.5V PP AC sine wave through it with no probs.

No smoke, no warmth on the chip (so far), as far as I can tell sine in = sine out.

So there you go. If anyone has a reason why I shouldn't be doing this - please chime in.

J