T.SAIKRISHNA,N.SRINIVAS,P.MAHENDER REDDY

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WHAT IS DECORATION LIGHT?
INTRODUCTION
 It is Heartwarming, brilliant and cool too.
 This circuit can be applied in many ways.
 The basic circuit can build with a set of 5 LEDs which can decorate according to design.
 You can buy a readymade decoration piece or design and make your own.
Components list
Semiconductors:
 IC1 -7555timer.
 IC2 -CD4040 binary counter.
 IC3-IC8 -74HC164 shift register.
 IC9 -UM66 music generator
 IC10 -78S05,5V regulator
 T1,T2 -2N3904npn transistor
 LED1-LED61-5mm LED
 D1-D4 -1N5408
Resistors:
 R1,R2 -1K ohm
 R3,R66 -470 ohm
 R4-R63 -220 ohm
 R64 -1.5k ohm
 R65 -330 ohm
 R67 -390 ohm
 VR1-20k ohm preset
Capacitors:
 C1-100uF, C2-0.01uF ceramic
 C3-C4-10uF, C5-1000uF
 C6-0.1uFceramic disk
 LS1:8ohm,0.5W speaker
 X1:AC to9V transformer
Description on LEDs
A light-emitting diode (LED)is a semiconductor light source.
LEDs are used as indicator lamps in many devices, and are increasingly used for lighting.
Introduced as a practical electronic component in 1962,early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet and infrared wavelengths, with very high brightness.
IC 7555 timer
 The IC7555 is stable controller capable of producing accurate time delay or frequency.
 Which determined oscillation frequency.
 The 555 is a highly stable controller capable of producing accurate timing pulses.
With a monostable operation, the time delay is controlled by one external resistor and one capacitor
 CD4040 is 16-stage ripple carry binary counter.
 The counters are advanced one count on the negative transition of each clock pulse.
 The counters are reset to the zero state by a logical “1” at the reset input independent of clock.
 Low power consumption: special CMOS oscillator configuration.
 Monostable (one-shot) or astable (free-running) operation.
 True and complemented buffered outputs.
 Only one external R and C required
IC 74HC164 shift register
 The 74HC164 is a high speed CMOS 8 bit SIPO shift register fabricated in silicon gate C2MOS technology.
 The HC164 output is from[3,4,5,6,7,10,11,12,13] each of the eight stages. Data is entered serially through one of two inputs(A or B), either of these inputs can be used as an active high enable for data entry through the other input.
 Each low-to-high transition on the clock input shifts data one place to the right and enters into QA.
 The logic NAND of the two data inputs(A&B) the data that existed before the rising clock edge.
 All inputs are equipped with protection circuits against static discharge and transient excess voltage.
 It consists of a no of single-bit D-type flip-flops connected together in chain arrangement, so o/p from one flip-flop becomes the i/p for the next flip-flop and so on.
UM 66music generator
 UM66 is a pleasing music generator IC which works on a power supply voltage of 3V.
 The required 3V supply is given through a zener regulator.
 Its output is taken from the pin1 and given to a push pull amplifier to drive the low impedance loud speaker.
 A class A amplifier before push pull amplifier can be used to decrees the noise and improve the output.
 Dynamic speaker can be driven with a external NPN transistor.
 It is 62 note ROM memory.
 1.3V-3.3V operating voltage rating and low power consumption.
Applications
TRAFIC SIGNAL:The first commercial LEDs were commonly used as replacements for incandescent and neon indicator lamps, and in seven-segment displays, first in expensive equipment such as laboratory and electronics test equipment, then later in such appliances as TVs, radios, telephones, calculators, and even watches.
 Visual signal application where the light goes more or less directly from the LED to the human eye, to convey a message or meaning.
 Illumination where LED light is reflected from object to give visual response of these objects.
 Generate light for measuring and interacting with processes that do not involve the human visual system.[85]
 Narrow band light sensors where the LED is operated in a reverse-bias mode and is responsive to incident light instead of emitting light.