How Do I Hook Up this Switch DG212?

Thread Starter


Joined Nov 11, 2013
I am building a sample and hold circuit for use in a SAR ADC and it has been suggested I use DG212 for the switch. I've attached the pinout diagram for this chip. I know S and D are for the signal path and IN is for the switch control signal. I'm just somewhat confused by V+, V-, GND, and VL. The data sheet says a VL supply is not required, but I don't know what it's for though. The supply voltage for the whole sample and hold circuit will be 0-5V. Can someone clarify V-, GND, and VL for me please?

Thank you,
DG212 Pinout Diagram.jpg



Joined Feb 24, 2006
You must have read the datasheet to find out that VL is not required. If you read the datasheet more carefully you'll probably discover that it is for the "logic" supply voltage. If you read the datasheet even more carefully you might find out what the threshold voltages are that define a logic "0" and a logic "1". Being that this is an "Analog Switch" I'm going to guess, but you should confirm, that V+ is the "most positive" analog voltage the chip will see, and V- is the most negative voltage that the chip will see.

Now is there some reason why you could not have taken the time to read the datasheet carefully given that this is your project and you would prefer not to make a mistake that would let the magic smoke out of the chips?