Dear Martin, I would ask your attention for the 74HC4316, made by Philips and the M74HC4316 made by SGMicroelectronics. I have the idea the SGM has a little bit beter specs. Their advantage is that they switch signals which are symmetrical to ground, without the need to change the level. The supply voltages are + and - 6.5V max. (+ and -6V recommended)
As for the specs, I conclude that signals can be switched between +Vdd and -Vss (SGM calls them Vcc and Vee). I use this type in a design for switching some hihger voltages, but I use 2 transmission gates for each analog signal. Allways one of the 2 is on. One is switching to the output, the other is switching to ground. Both switches have one input resistor in common. One switch has the output resistor to ground, the other to an opamp - input (virtual ground). So in both branches the signal is divided by a voltage divider and the analog input voltage at the switch's input never exceeds the allowed value. But it costs you 2 transmission gates per switched signal and an inverter for the logic control signal. Regards, Harry > As an electronics experimenter who is blind, I write down the > pin-outs of chips I am working with in Braille in a notebook. > Sometimes, I forget to write down crucial details that I just know > I'll remember as well as I do my name, but my brain sometimes doesn't > remember as well as I'd like. > > Are the Control lines for the 4 bilateral switches of a CD4016 > or a CD4066 active low or active high? > > I am going to be running one or two of these chips from a PIC, > actually, via a 7405 open collector hex inverter to shift levels from > +5V to +12v where the bilateral switches can switch a larger voltage > range. The neat thing about the PIC is that I will just write the > firmware to fit the polarity requirements. > > Those who have ever switched audio with a CD4016 or 66 know > that when the switch is open, voltages that exceed VDD/2 will slip > through anyway. With 12 volts, this raises the breakdown threshold to > +-6 volts rather than +-2.5 volts. -- Author: H.C. Croon INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB CHIPDIR-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
