I am using an Arduino Micro for some Infra Red Remote home automation. I accidentally soldered away the contacts on my 3.3 volt pinhole. My IR receiver works anywhere from 2.7 to 5.5 volts. So I attached it my 5 volt pin. I've noticed with a simple IR incoming code serial print that different hex codes come in when i press the same button on my remote. I press a button and at that moment the hex code comes up but I rarely get the same codes multiple times. I could be wrong, but I think the IR receiver doesn't work as well under five volts.
I want to know how to get five volts down to something like 4 volts with a resistor.
The most information I found was equation breakdown, tutorials, and calculators for LEDS but I was hoping for something that worked better with my non-led needs.
Example: LINK
I took my best option and worked a little with the calculator. It was easy to get the source voltage (5) and the target voltage (4) but the current is more elusive. The spec sheet for the Micro says it puts out 50 mAmps. Does this mean it puts out a maximum of 50 mA's depending on its demands, or does it mean it always puts out 50 mA's? I used my multi-meter to measure the pin and found it was only putting out 0.02 mAmps. Is the current I want 50, .02, or the consumption of the receiver?
What resistor should I get?
Is there a better formula for dropping voltage for different non-LED components?
I accidentally soldered away the contacts on my 3.3 volt pinhole
Anyone else understand that?
AWOL:
Anyone else understand that?
I'm guessing he lifted the trace.
As far as current, the I/O pin CAN source (put out) up to 40mA of current. That means whatever you connect cannot use more than that, and less is better.
Whatever voltage divider you use will determine the total current being drawn from the I/O pin.
AWOL:
Anyone else understand that?
Yeah, I didn't know what the round piece of metal around the hole was called.
tinman13kup:
As far as current, the I/O pin CAN source (put out) up to 40mA of current. That means whatever you connect cannot use more than that, and less is better.Whatever voltage divider you use will determine the total current being drawn from the I/O pin.
tinman13kup Thank, you I now understand that is incorrect. Still some unanswered questions.
Is the led formula the right one?
If so what I should I use for the current?
If not: what formula should I use?
What IR receiver do you have? The datasheet will tell you how much current it requires. You could also hook your meter up in series between the 5V pin and the Vcc pin of the receiver and measure how much current it draws.
I could be wrong, but I think the IR receiver doesn't work as well under five volts.
You are wrong, if the data sheet says 2.7 to 5.5 volts that is what it will work with equally as well.
I rarely get the same codes multiple times.
That could be expected depending on the hardware and the code. Please post a schematic and your code. Be sure to include the part numbers.