[sdiy] 4049/4069 linear mode

[Scott Gravenhorst]

Dave Manley <dlmanley at sonic.net> wrote:
>Scott Gravenhorst wrote:
>> Derek Holzer <derek at umatic.nl> wrote:
>>   
>>> First off, are these essentially the same chip (aside from pin outs)
>>>     
>>
>> 4049 has an asymmetrical output current characteristic, 4069 has a symmetrical output
>> current characteristic.
>I wasn't aware of this tidbit.  This could be important if you want to 
>maintain the symmetry of a high frequency clock in a digital circuit, 
>but for use in linear mode at audio frequencies, does this result in an 
>audible difference?
>

4069UB sources and sinks equally (2.4mA), the 4049 sinks more than it sources (3.5mA source, 20.0mA
sink), but also sinks AND sources more than the 4069UB.  For the 4049, I would suspect that since
the sink and source transistors are that different, they would have different gain characteristics
as well.  This should produce a different distortion character especially when overdriven I would
think.


-- ScottG
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-- Scott Gravenhorst
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