4 Channel Led Chaser

                 This LED chaser display is build around readily available, low cost components.This circuit is easy for build for a beginner in the electronics. The power supply for the chaser circuit is from a 9v battery.The circuit diagram of the chaser is below.

                                                       Click the circuit for enlarging.

                The NE 555 timer ic and decade counter 4017 is the heart of the circuit. The astable multivibrator built around IC2 produces a clock frequency at its output pin 3. This output is connected to clock pin (pin 14) of the decade counter Cd 4017.The decade counter can count up to 10. But in circuit we only use 4 O\P so the Q4 (pin 10)  is connected to the reset (pin 15) of the CD 4017. The output of IC3 advances by one count every second (depending on the time period of astable multivibrator IC2). The VR1 connected between the Pins of IC2 determine the speed of the glowing of the bulb.

4000 Series IC

                       There are many ICs in the 4000 series and this page only covers a selection, concentrating on the most useful ICs. Most gates and a few counters are covered. For each IC there is a diagram showing the pin arrangement and brief notes explain the function of the pins where necessary.