Electronic Circuits for the Evil Genius 2/E

SECTION 12The 4017 Walking Ring Counter

SO WE HAVE A CLOCK signal output. It rolls down to a complete stop. Now to expand from 1 LED to 11 LEDs. They don’t all go on at once. It actually counts: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1, 2, 3, . . . and higher if you want to use the carryout capabilities.

Lesson 40 Introducing the Walking Ring 4017 Decade Counter

Here is the system diagram for the prototype application of the 4017 IC (see Table L40-1).

Be very careful not to use too much space. There are still two major circuits to fit onto your board. All of the cathode sides of the LEDs can be ganged onto the unused line on the bottom as shown in Figure L40-1 (see the Parts Bin). The common resistor can connect the LED line to ground.

Figure L40-1 ...