component choices.txt

geometric contraining equation for the number of turns usable by a given
inductor
n_g = floor(((d_out - 1/2*w) - (d_in + 1/2*w))/(2*(w + s)))

input offset voltage of the cmp04 is 1mv, this limits the minimum voltage 
differential for the inductor

current draw of each of the components used:
ATmega32u2:  0.050 mA
cmp04:       0.012 A
TPIC6B595:   0.050 A
mcp4821:     0.050 A
8x100k(ohm): 0.00005 A
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          = 0.163 A
fudge:    + 0.062 A
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          = 0.225 A
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max:      - 0.475 A
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          = 0.200 A  : free current for use in the keyswitch matrix
          
to limit current:
    5/0.025 = 200 Ohms
    0.025*8 = 200 mA

this means that a total of 25mA is available to each inductor
in simulation (with perfect components) to achive a net voltage differential of
at least 2mV a 4kHz frequency is needed, given a large enough induction upon.
switch closure. a custom firmware or another controller is needed