74C164 8 bit shift register work as a heart for car LED light sequencer

This Car LED Light Sequencer uses a standard 74C164 8 bit shift register as its heart of operation. The 74C164 is also known as a 8-Bit Parallel-Out Serial Shift Register which is a monolithic complementary MOS (CMOS) integrated circuit. These 8-bit shift registers have gated serial inputs and clear. Each register bit is a D-type master/slave flip
74C164 8 bit shift register work as a heart for car LED light sequencer - schematic

-flop. Data is serially shifted in and out of the 8-bit register during the positive going transition of clock pulse. Clear is independent of the clock and accomplished by a low level at the clear input. It has a wide supply voltage range from 3V to 15V DC. The input data goes to the serial inputs at pin 1 and 2 which are connected to VCC of the circuit. When pins 1 and 2 are high, the data moves one step forward with each clock pulse. As shown in the diagram above, the outputs are pins 3-6 and 10-13. The data flows from output 1 to 2 to 3. to 8 with each positive edge of the clock pulse. The data can be cleared to zero by putting a momentary low input at pin 9. Two gates of 4011 quad two input NAND gate IC2-a and IC2-b are connected as an astable oscillator circuit with the frequency of operation set by C1 and R11. The clock`s positive output pulses at pin 4 of IC2 are connected to the clock input of 74C164. An LED with a resistor of 1K each is connected to the outputs of the shift register. The shift register`s 8th output atpin 13 is connected through a RC network delay circuit of R10 and C3. When the 8th clock pulse turns on LED8, pin 13 of IC1 goes positive, charging C3. After a period of time, IC2-c output goes low clearing the shift register outputs. The first clock pulse turns LED1 on, the second LED2, the third LED3 until all eight of the LEDs are lighted ON. After the8th LED turns ON, the clear pulse from IC2-c...

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