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b. CD4051 (U2): This chip is called a “multiplexer.” This multiplexer allows the microcontroller
to continuously sample the value of each potentiometer, one at a time.
i. Install the multiplexer in location U2. For it to fit easily into the holes, you may have
to gently bend the leads closer together, pushing each side of the chip down on a flat
surface (46,47). Notice the divot at one end of the chip. There is a matching shape on
the PCB graphic. Press the IC down snugly with your fingertip (48).
ii. Tack one leg down with solder on the component side (49).
iii. Now flip the board over and finish soldering the rest of the leads (50,51).
46
47
48
49
50
51
