The [ULN2003 Arrary](http://www.ti.com/lit/ds/slrs027o/slrs027o.pdf) contains 7 darlington transistors connected with common emitter. [![enter image description here][1]][1] There is even a base resistor included. You could choose which voltage level you desire, such as ULN2002, 2003 or 2004 [![enter image description here][2]][2] [1]: https://i.sstatic.net/wWujy.jpg [2]: https://i.sstatic.net/0nb1b.jpg