Somehow I ordered a KIT DIY kit with AliExpress - running lights on LEDs (). I was attracted by the ridiculous price of 63 rubles and the opportunity to practice soldering SMD radio elements.
This designer consists of a printed circuit board measuring 20x55 mm and, accordingly, a set of necessary radio components. The board indicates the installation locations of all components and their ratings, so there are no special difficulties with installation.
The entire manufacturing process and the operation of the circuit can be seen in the video:
The list of tools and materials
- a set of running lights on a CD4017 or K561IE8 chip ();
-screwdriver;
- scissors;
soldering iron;
Cambridge;
-accumulator battery from a cell phone;
-12V power supply;
-connecting wires;
-folded textolite for printed circuit board;
microchips K561TM2;
-resistors;
KT815 transistors (or analogs);
LEDs.
Step one. PCB soldering kit with AliExpress.
All that is needed is to solder the kit components to the board. In view of the miniature size of the SMD radio elements used a "third hand" with a magnifying glass. First, I soldered resistors, capacitors, and other components of the circuit except microcircuits. At the end, we solder the microcircuits and LEDs.
This circuit works from 3 to 15V. The pulse generator is assembled on a NE555 chip, then the pulses are fed to a decimal counter with a decoder-microcircuit CD4017 (K561IE8), to the ten outputs of which LEDs are connected via current-limiting resistors. The switching speed of the running lights is regulated by a trimming resistor.
The scheme of the constructor.
My scheme worked the first time I turned it on.
Second step. Modernization of the scheme of running lights.
Later, during the experiments, the CD4017 chip failed. By quick on the wires I had to replace it with a domestic analog K561IE8.
I wanted to get more interesting lighting effects of running lights. As a result, he assembled another printed circuit board with K561TM2 triggers and power switches on the KT815. The pulse from each output of K561IE8 is fed to the trigger input according to the "latch" principle, that is, the signal remains constant at the trigger output until a reset pulse arrives from leg 11 of the CD4017 chip (K561IE8).For a cycle 9 channels are included. Power switches on transistors KT815 are designed to connect the load up to 1-1.5A. If you need to connect a more powerful load, then you need to replace the KT815, respectively, with more powerful transistors. Since I applied four K561TM2 microcircuits, an eight-channel circuit was obtained. In this circuit, you can get 9 LED control channels, but then you need to add another K561TM2 chip to the circuit by connecting one trigger (the K561TM2 chip consists of two triggers), and also add one transistor key.
Scheme after alteration ..
To check the operation, I connected pieces of LED strip with three LEDs to each of the eight channels.
Replaced the tuning resistor 50kOhm with 470kOhm to expand the limits of the pulse frequency adjustment. Found in the garage the old lampshade from the turn signals, covered him with an LED strip. The lighting effect was pretty good.
This is the design of the weekend. It was interesting to break in a new scheme, so everything was done quickly. In the future, it will be possible to make a new common printed circuit board. It’s up to the beginner to make such running lights on LEDs on his own without a lot of time and money. And where to apply them is up to you.
A couple of weekend nights and 63 rubles (.) Went to all the work. The rest of the components I had were in stock.