NN	Part			Digikey Link		Qty		Price
1	Capacitor 1uF		587-2477-1-ND  		1		0.23 
2	Capacitor 22uF		1276-6780-1-ND		1		0.38
3	Microcontroller		EFM32ZG110F32-QFN24T-ND	1		1.42
4	Connector header	S9005E-05-ND		1		1.00
5 	TPS62172		296-39449-1-ND		1		1.53
6 	Inductor 2.2uH		587-2905-1-ND		1		0.35
7 	Capacitor 100nF		587-1456-1-ND		6 (buy 10)	0.56
8	Button			401-1810-ND		2		0.58 x2
9	Battery holder 4xAA	36-2478-ND		1		1.78
10	Matrix controller	1528-2452-ND 		1		5.95
11	Voltage shifter		296-17988-1-ND 		1		0.68