I've successfully run at least one of these with a V_l (logic level voltage) of 15V while controlling the chip from a 5V MCU.
As I considered doing this for all switches (but with 3.3v logic level), I did a quick search that turned up these three posts:
"How do I connect the DG403 logic supply (VL) pin?"
"switches - VL input on analog switch"
"Analog Switch switching voltage (DG412)"
They don't give the exact same answer though. The Renesas one says to use a 5V supply (even for 3.3v logic), derived from the 15V using a resistor voltage divider with high value resistors.
Now, they may not be talking about the same chip as the DG series are produced by a variety of suppliers, but at least it sort of validates just using a voltage divider.
The stack exchange post starts talking about excessive current draw.
The modwiggler post suggests using zener diodes or a resistor divider connected to an emitter follower.
For now, I'll stick with V_l = 5V but I'll test doing it with a resistor divider.
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