I am super new to this whole world. I am currently working on a Ghostbuster Proton pack for my son which is heavy on different types of lights and sounds. I am looking at going with the Mega in order to have enough GPIO pins.
I wanted to pitch my idea and get guidance on proceeding. I want to flip a switch that turns on all of the main components immediately, these include:
LED Chaser sequence run by another board (see below)
4 LED Chaser sequence
LCD Bar Graph Display
various individual lights
1)Prior to coming to the late realization that I will need to use some type of micro controller, etc. I purchased this item BK116 Chaser Kit, 16 LEDs for my pack. I reached out to the company asking them about controlling it with an Arduino and this is the reply I got:
On the Arduino, the BK-116 normally requires 6 to 16 volts @ 100ma DC to power it, so not sure if you can get that out of an Arduino output pin! If you wanted to modify the BK-116 to bypass the protection diode and voltage regulator, it could run off 5 volts DC, but may be too much power on the Arduino pin!
This shouldn't be too hard of a project if you have electronics experience. If you get in a bind, feel free to PM me. Here's some initial guidance:
Use the Arduino to control the signals, but not to source them. You were right when you said:
ajdeployed12:
On the Arduino, the BK-116 normally requires 6 to 16 volts @ 100ma DC to power it, so not sure if you can get that out of an Arduino output pin!
The way to work around this is via relays or power MOSFET transistors. Namely, the Arduino sends a signal to the relay (or MOSFET) that controls how much current is being supplied to the lights from an external power supply. You'd have about one relay/MOSFET per light module you want to drive and you would need a VERY hefty battery (or network of multiple) in order to supply the lights.
If I were you, I'd use normally off single pole single throw relays with 330 ohm shunt resistors. If that was confusing, google it.
Thank you for all of the responses. I think that I will go with a relay. The circuit of the chaser run by another board (in hindsight a huge waste of my money) will be will be complete and powered by a 9v battery. I will insert a relay that will allow the Arduino to act as an on/off switch. Since I currently have no idea what I am seeing when I look at a schematic; do I want to insert the relay on the positive or negative side of the circuit? Or does it matter?
A SPST relay has two ports: input and output. Each of these ports have two "rails" that you connect to the main circuit with.
For the input port, you will connect the Arduino signal output (used to determine if you want the LEDs on or off) to one of the input rails. You will then connect the Arduino GND (ground) to the other input rail. You'll have to refer to the relay's datasheet to determine which input rail gets signal and which gets ground.
For the output port, you connect one rail to the positive terminal of the battery (or to a shunt resistor if you need one) and the other to the positive input of the LED circuit. This is just one of several ways to wire the relay output port, but it will work.
