Abra AK-72 User manual

Running Flow LED
Light NE555 +
CD4017 Module –
D.I.Y. Kit
Running Flow LED
Light NE555 +
CD4017 Module –
D.I.Y. Kit
AK-72

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Table of Contents
1. Description ………………………………………………………………………………………………………………. 3
2. Specification …………………………………………………………..…………………………………………..…… 3
3. IC pinout ………………………………………………….………………………………………………….…………… 3
4. Component List …………………………………………………………………………………………………...….. 4
5. Assembly ……………………………………………………………………………………………………………..….. 5

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Description:
This D.I.Y. package comes with all the components you need to assemble and solder a
running LED module.It has adouble-sided board with surface mount and through-hole
configuration. It is designed for users with advanced soldering skills. You must solder some
components on the top surface and some components on the bottom side of the board. The
assembly process should take anywhere between 30 minutes to an hour.
The NE555 chip is designed to output a square wave signal based on the resistor values
of its voltage divider and the capacitor values. This essentially generates aclock signal which
turns the LEDs ON one after the other in sequence.
This module works with a supply voltage of 2.5 to 14.5 DC Volts. The NE555 astable timer
works in conjunction with 4 resistors (R1, R2, R3 and R4) and they charge the C1 capacitor. This
capacitor is discharged through R3 and R4. The oscillation is created at the output pin (pin 3) of
the NE555 chip as the C1 capacitor charges and discharges. This oscillated signal is provided to
the clock input (pin 14) of the CD4017 chip. This chip is a logic-based counter which provides 10
outputs to be used by the LEDs. The outputs pins are pin 1 to 7 and pin 9 to 11.
Specification:
Required Input Voltage: 2.5 to 14.5VDC
Circuit Board Size: 54mm x 20mm (2.13 in. x 0.79 in.)
IC Pinout:
The following figures indicate the pinout configuration for both ICs:

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Component List:
This packaged includes 28 pieces which are listed below:
1) 1x PCB –Printed Circuit Board
(doubled-sided, tin plated, blue soldermask, white silkscreen)
2) 10x 1kΩ SMD resistors –R1, R5, R6, R7, R8, R9, R10, R11, R12, R13
3) 2x 2kΩSMD resistor –R2 (1x spare)
4) 2x 10kΩSMD resistor –R3 (1x spare)
5) 1x 50kΩ variable resistor (potentiometer) –R4

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6) 2x 1µF SMD capacitor –C1, C2
7) 1x NE555P SOIC IC chip –U1
8) 1x CD4017BM SOIC IC chip –U2
9) 10x 3mm red LEDs (not labeled)
10) 1x single row 2-pin header (not labeled)
Assembly:
1) In order to assemble the module, you need the following tools:
*It is recommended to have some isopropyl alcohol and a fine soldering brush handy to
clean off the excess flux on the circuit board when done soldering.

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*ATTENTION* DO NOT USE RUBBING ALCOHOL, IT WILL DAMAGE THE COMPONENTS.
2) Open the package and verify the components. (refer to section 4. Component List on page
4 for this step)

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3) Take out the ICs, resistors and capacitors from their package by removing the clear tape
and leave them on your workbench for the next step.
*ATTENTION* SURFACE MOUNT COMPONENTS ARE VERY SMALL. DO NOT LOSE THEM. IT IS
RECOMMENDED TO USE YOUR PLIERS WHEN YOU ARE HANDLING THEM.

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4) *OPTIONAL* It is best practice to check component values using proper equipment (i.e.
Using a Digital Multimeter to verify the ohmic value of the resistors) before proceeding to
the next step.
5) Prepare your soldering tools.
a) Make sure the soldering tip size is correctly chosen and it is clean.
b) The soldering iron temperature depends on the type of solder used.
c) If you are using a typical 60/40 lead solder, depending on the thickness the
temperature should be set anywhere between 370 to 500 °F (187 –260 °C). If
you are using a lead-free solder, increase above temperatures by 40 to 70 °F (5
–20 °C).
*ATTENTION* HIGHER TEMPERATURES WILL DAMAGE THE COMPONENTS ALONG
WITH THE CIRCUIT BOARD.

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*ATTENTION* DO NOT TOUCH THE SOLDERING IRON TIP WHEN IT IS HOT.
d) It is recommended that you clean the board with a brush, isopropyl alcohol and
lint-free cloth to get rid of any glue or dirt. This way the solder will create a
better joint with the pads.
e) Have your flush cutter handy.
f) Having a roll of paper tape helps you to keep the components in place when
soldering. *ONLY FOR THROUGH-HOLE COMPONENTS*
g) Have a rosin flux pen or paste handy. Adding flux to the pads before soldering
the component makes the process easier.
*ATTENTION* SOLDERING SHOULD BE DONE IN A VENTILATED AREA. BREATHING
SOLDER FUMES WILL HARM YOU.
6) Start the assembly by soldering the SMD resistors, capacitors and ICs. Add an appropriate
amount of solder to one pad at a time. Place each component in its designated location
by using your pliers while heating up the previously added solder so it melts again and
covers the component lead. Once the component is stuck to its location, add solder to the
other lead/pad to secure the component and create a connection.
Repeat this process until all your resistors, capacitors and ICs are soldered on the circuit
board.
Refer to the illustrations below:

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11

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Once all the surface mount components are soldered on the board, proceed to the next
step.
7) Place the variable resistor (R4) in its designated location and solder the leads on the
bottom side of the board.

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8) Insert the LEDs and solder the leads on the bottom side of the circuit board. You can
secure the LEDs by taping them down on the top side of the board or by slightly bending
their leads. You can solder them all at once or one by one.

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9) Your circuit board should look like this if you have proceeded up to step 8.
10) This kit provides a single row 2-pin header that can be used to power up the module. You
can solder them if you have access to jumper wires or a pair of alligator clips. Otherwise,
solder two pieces of wire to the positive (+) and the negative (-) leads on the board.
11) Using your brush, isopropyl alcohol and lint-free cloth, clean the board thoroughly and
make sure no flux residue is left.
12) Prepare your power supply, alligator clips and jumper wires. Follow the recommended
specs to adjust the power supply before connecting the leads. (refer to section 2.
Specification on page 2)

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13) When your running flow LED module is turned ON, grab a small flat head screw driver and
adjust the variable resistor (R4) to set the speed of the running LEDs.
14) You have completed the assembly of your module.
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