TIP 120 driving a motor:
Pull down resistor configuration:
Read multiple
switches using the ADC at a single analog port instead.
Vout = Vcc (R2/(R1 + R2))
Va = 5 (Rz/(Rz + Ra)) = 4.5
Va = 5 (Rz/(Rz + Ra + Rb)) = 3.6
Va = 5 (Rz/(Rz + Ra + Rb + Rc)) = 2.7
Va = 5 (Rz/(Rz + Ra + Rb + Rc + Rd)) = 1.9
