Particle Electron with 12v & ULN2003

Hello Guys,
I am new to the particle devices.
as per the datasheet of the particle Electron supports 12v.
please tell, what ampere rating power adapter should I use.
I want to control latching relays with I have used ULN2003 driver ic.
Is it the right choice?
Here is my project design.

thanks in adavnce.

It depends on whether you’re also using the LiPo battery. You need a minimum of 1800 mA @ 3.6V = 6.48 watts if you do not include the battery. To be safe, I’d use a 1A @ 12V power supply, though you could go lower than that, depending on the current draw of your relays.

1 Like

Thanks @rickkas7
Should I include Bulk capacitor in parallel with 12v input??

Adding a cap is probably a good idea.

And your ULN2003 includes the flyback diodes so you’re set, but for anyone driving the relay coils directly with a MOSFET, don’t forget the flyback diodes.