Hello,
I saw at the datasheet of the 74HCT4052 Multiplexer-Demultiplexer two parameters that seems similar to me but have different values. The parameters are the VI (input voltage) and the VSW (switch voltage). Why the range of the VI voltage isn't between VCC-VEE like VSW voltage? As I understand this analog Multiplexer can have on his selected input a signal/voltage between VCC-VEE and if the output will enabled the input will pass on the output (little smaller because of the RdsON of the switch) or am I wrong?
Page 6
https://assets.nexperia.com/documents/data-sheet/74HC_HCT4052.pdf
That nexperia datasheet is poor: the PSU pins are inconsistenly labelled. TI's datasheet is at least consistent.
I suspect you are missing the key point: there are logic level translators inside the device.
The logic select controls are defined by Vih and vary with different Vcc voltage.
The analogue inputs can be between Vcc and Vee. Possible values are Vcc=+5V and Vee=-5V, but others within the limits stated are possible, e.g. Vee=0V
To clarify point above, that test circuit does not match the specs you are referring to, which is causing the confusion.
VI is not Vis on the diagram as you've drawn.
VI is from GND to Sn pin.
VI = VIH or VIL; for test circuit see Fig. 7.
Vis is the input voltage at a nYn or nZ terminal, whichever is assigned as an input.
Vos is the output voltage at a nYn or nZ terminal, whichever is assigned as an output.
Vis range = Vos range = Vee to Vcc.
Vis range could be the same thing with the Vsw range?
Also, as I know the logic level conversion is when a chip takes for instance a CMOS voltage 12V and converted into a TTL voltage 5V or vice versa. At this chip whatever voltage will be applied between the range of Vcc-Vee will go out the same theoretically (practically little smaller because of the RDSon of the switch), so what have about to do the logic level conversion block inside the chip?
Please read TI's or On Semiconductor's datasheet.
For my opinion the ON Semiconductor’s datasheet is the most detailed. It clearly writes at the first table on the page 4 that Vis is the analog input voltage of the switches and the Vin voltage it corresponds to digital voltage (in respect to GND) and more precisely to control pins.
At page 10 the datasheet describes with an example the functionality of the chip. As I understand the logic level converter is referred in the function that with a positive digital signal (e.g. 0-5V) can controlled a Vp-p analog signal (e.g. +5 - -5V; with negative values). The logic level converter takes as input a digital positive signal and then creates on his output a proper signal in order to drive the gates of the mosfets/switches that are between each analog input/output.
Also, a very good detailed datasheet where is similar to 4052 is the 14052 datasheet.
P.S. If anyone understand the reason that at Nexperia's datasheet referred the term Vsw (or the Vsw is the same thing with Vis in essence?) and if there is any practical purpose of it... please tell it.
Thanks all of you for your replies and the help.
P.S. If anyone understand the reason that at Nexperia's datasheet referred the term Vsw (or the Vsw is the same thing with Vis in essence?) and if there is any practical purpose of it... please tell it.
Sloppyness is a sufficient explanation. The Nexperia datasheet also uses Vcc and Vdd interchangeably. That's sufficient for me to avoid Nexperia where possible.
The onsemi datasheet is better than the TI datasheet which is in turn better than the Nexperia datasheet.
Onsemi is American; was Motorola.
Nexperia is Chinese; was Philips.
TI is American, and always was TI.