ULN2803C: GND Pin (9) Connection to Negative Voltage

Dan Hembree

Part Number: ULN2803C

Tool/software:

Can the GND pin (9) be connected to a negative voltage other than circuit ground? I would like to use this device to drive 24V relays whose coils are connected to +/-12VDC. In this case the GND pin would be connected to -12V.

Thanks for the input.

8 months ago

0 Timothy Logan 8 months ago

TI__Mastermind 32065 points

Dan,

I conferred with our design team and this configuration would not be possible as there is this diode from ground to input:

A negative voltage would immediately bias this download and impede operation of device.

Best Regards,
Tim

0 Dan Hembree 8 months ago in reply to Timothy Logan

Prodigy 140 points

Timothy,

Thanks very much for the reply. That makes sense. I have another solution in my back pocket but would prefer to use a multi-channel device such as this.

Thanks again.

Dan

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ULN2803C: GND Pin (9) Connection to Negative Voltage