CD4060 14-Stage Counter Slow Blinker
Blink an LED once every two seconds, every two minutes, or every two hours — without an MCU. The CD4060 builds its own oscillator and counts to 16384.
Difficulty: Breadboard. Estimated build time: about 25 minutes. Estimated parts cost: about US$2.20. 9-line bill of materials. Compare supplier offers when available. A pure logic blinker that can pulse an LED at intervals from a fraction of a second up to many minutes, without a microcontroller and without a 555 + counter chain.
Build the RC oscillator
Put 5 V (or 3 V from a coin cell — the CD4060 works from 3 to 18 V) on pin 16, ground on pin 8. Connect a 100 k resistor between pin 11 and pin 10, a 1 M resistor between pin 10 and pin 9, and a 470 pF ceramic from pin 9 to ground. This RC network sets the oscillator to about 22 kHz. Tie pin 12 (the master reset) to ground — leaving it high resets the counter and stops everything. Add a 100 nF decoupling capacitor from VDD (pin 16) to ground right at the chip.
Wire an LED to a slow output
Connect a red LED through a 470 ohm series resistor between pin 3 (which is Q14, the slowest output, divide by 16384) and ground. Cathode to ground, anode through the resistor to Q14. Power up the circuit. The LED should pulse on and off every two seconds — about 22000 / 16384 ≈ 1.3 Hz, so a one-second-on, one-second-off rhythm. Touch a finger across the 1 M resistor and the LED slows down (your skin adds parallel resistance). To go even slower, move the LED to Q13 (pin 2, twice as fast) or chain another /2 counter for a 4-second period.
Use it as a timing source for a real project
Replace the LED with an N-channel MOSFET driving a buzzer, a small motor, or a relay coil. Now you have a fire-and-forget interval timer that costs about 50 cents. For a 32.768 kHz watch crystal between pins 11 and 10 with 22 pF from each pin to ground, the output frequencies become exact powers of two — Q14 is exactly 2 Hz, a perfect heartbeat. Hold pin 12 high momentarily to reset the count to zero — that gives you a 'start' button for a one-shot timer.