NXP

user Occupation hasn't been added

 NXP Semiconductors


  • LED Illumination Circuit for 4x12 ft. Aquarium

  • Created: Dec 09, 2014

    • view543
    • comment0
    • bookmark0
    • fork0

Description

No description available.

Summary

The LED illumination circuit is designed to light a 4x12 ft. aquarium using LEDs. It uses uses 74LV4060D IC, a low-voltage Si-gate CMOS device that has a 14-stage ripple-carry counter/divider and oscillator optimized for low voltage applications. The IC is responsible for the lighting sequence of the circuit where the blue and white LEDs light alternately at an interval of 12 hours.


The diagram shows a simple circuit based on the universal timer IC 4060 for implementing the sequencing operations of the LEDs. In the circuit, the product of R2 and C1 determines the timing frequency that is set for generating 12 hour intervals. A small value resistor may be selected for R2 to check what time interval it generates. If after a few days the time intervals seem to be drifting away from the set start/finish hours, the switch SW1 may be pressed for resetting the sequence. If required this can be done every morning at 9am for implementing accurate switching of the LEDs, and for maintaining a natural feel inside the aquarium habitat. Assuming the circuit is switched ON at 9 in the morning. The output pin 3 of the IC initiates with a logic at low state and the timer will start counting. The low state at pin 3 keeps Q1 to switch OFF which creates a high potential at the collector of Q1 that instantly triggers Q3/Q2 in driving the white LEDs. The white LEDs remains illuminated and the moment the set time lapses, the output of the IC goes high and instantly switches ON Q1 to drive the blue LEDs and switches OFF Q2/Q3 making the white LEDs to turn OFF. Moreover, C2 and C3 helps to illuminate the respective LED banks gently, in a cool fading manner.The white LED bank is made by connecting 116 nos. strings connected in parallel. Each string consists of 3 white LEds with a 150 Ohms resistor while the blue LED bank is also made by connecting 51 nos. blue LED strings in parallel.


LED illumination circuits are generally applied not only to aquariums but also to any other instances or events that needs good lighting system such as museums, gardens and ponds where its sequence of lighting may be adjusted by altering the values of the capacitors and resistors. Furthermore, different ambience may be achieved based on the timing and LED color preferences of the user.