uln2003a can COM pin be GND?

[DaKandEKid]

Most configurations have it so a voltage like +12V is connected to the COM pin of a darlington transistor array.

I don't quite understand the schematic of the darlington transistor array and i was wondering if it's possible to switch the grounds on-off rather then the power.

What i'm trying to accomplish is i have 4 loads i need to switch which have a power supply of 12V and 2 loads which are powered by 5V. Initially i designed my circuit using a number of 2n7000 mosfets and it worked great. Now i'm optimizing my design and it's cheaper to using a darlington array then using seperate mosfets for each device. Additionally, i've added some inductive loads (relays) so the internal clamping diodes are a plus.

Is it possible to have the darlington array switch grounds?

Thanks in advance!

 

[Sebi]

The 2003 outputs are NPN darlingtons with COMMON emitters, and open collectors. So the common must be negative or GND. The load connected between open collector and +power up to 50V.