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I have a couple of SGM3005 chips and want to use them as switches in an audio circuit, but they don't support negative signals. The classical solution would be to bias the COM1 input, right? But, what if instead of biasing the input pin, I apply some negative voltage to the GND pin, will it work?

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http://www.kean.com.au/oshw/oximeter/SGM3005%20Dual%20Analog%20Switch.pdf

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You could power the switch part between +2.5V and -2.5V. Part only supports 5.5V Max. This would allow 0V centered signals to pass through the switch.

You will need to arrange the switch control signals to swing from the negative rail to the positive rail.

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  • \$\begingroup\$ You mean to apply 5V to COM1? \$\endgroup\$
    – Gabriel Santos
    Mar 14, 2020 at 20:43
  • \$\begingroup\$ No way. Com 1 is a signal path pin not a bias pin. \$\endgroup\$
    – Michael Karas
    Mar 14, 2020 at 20:44
  • \$\begingroup\$ You use com 1 and com 2 as signal path points that may or may not be connected to NC1/NC2 or NO1/NO2. \$\endgroup\$
    – Michael Karas
    Mar 14, 2020 at 20:47
  • \$\begingroup\$ Wouldn't it work if I bias the COM1? And, by "You could power the switch part between +2.5V and -2.5V" you meant to apply +2.5V to V+ and -2.5V to GND? \$\endgroup\$
    – Gabriel Santos
    Mar 14, 2020 at 20:49
  • \$\begingroup\$ Forget your biasing idea. Connect V+ to +2.5V and pin 6 to -2.5V. make sure signal amplitude stays lower than those rail levels and mind what I said about the switch control signal on pin 4. \$\endgroup\$
    – Michael Karas
    Mar 14, 2020 at 20:54

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