The standard programming technique for Arduino boards is to open the Arduino IDE (or possibly Visual Studio Code), connect your board using a “regular” USB port, choose the appropriate choices, and press the upload button. On closer inspection, the Arduino Pro Mini does not appear to have a USB port, though.

What is Arduino pro-Mini?

Arduino Pro mini is a tiny, microcontroller board designed to help you bring your ideas and projects to life. It’s powered by an Atmel ATmega168P/328P-AU microcontroller operating at 16MHz with 32KB of flash memory. As well as the direct control over hardware and simple coding language, Arduino Pro Mini offers several advantages that make it ideal for various projects.

Arduino Pro mini USB Serial

On one side of this tiny board, there are six pins that can be used to connect an FTDI cable for serial data transfer. The onboard USB-to-Serial conversion is eliminated, and the workload is transferred to a separate device that may be plugged in and powered on as required.

This arrangement also eliminates the cost of the onboard chip itself and the additional power needs for something that is only occasionally used. The drawback is that a particular cable is required to make the connection, which might be challenging for beginners.

The Arduino Pro Mini is a terrific option if you are a little more experienced and need something small, effective, and affordable, but it won’t replace the Uno as the de facto first-maker board. With a smaller PCB, its footprint is around 1/6th that of the Arduino Uno at 1.3″ x.70″ or.91 in2. If weight savings are crucial for your application, doing this should result in a small reduction.

These boards are available in both the 3.3V and the 5V versions. So, at least that part is easily replaceable if you happen to, say, crack one affixed to your drone in a crash. We’ll talk about how these boards can be quite power-efficient in a moment.

Let’s talk about programming these tiny boards first given their advantages.

Programming Arduino Pro Mini 

The Arduino Pro mini programming board comes preloaded with the latest version of the Arduino IDE software, allowing you to quickly get started creating and testing your own sketches.

These boards are available in both the 3.3V and the 5V versions. So, at least that part is easily replaceable if you happen to, say, crack one affixed to your drone in a crash. We’ll talk about how these boards can be quite power-efficient in a moment.

Let’s talk about programming these tiny boards first given their advantages.

Connect the cable to your computer, choosing the correct port, voltage, and CPU type. When you press the upload button, your board should begin to obediently blink a little while later. While Linux or Windows should function similarly, I’m using a Macintosh here.

Arduino Pro Mini 3.3V or 5V?

It is appropriate to utilize a device with a 3.3V supply when using a 3.3V board, such as this FT232RL UART Breakout Board, which can switch between 3.3V and 5V. Having said that, I was able to program the 3.3V board without incident by plugging it into the same 5V wire that I used for the 5V board. Though it might not seem like a big deal, proceed at your own risk.

Running the +5V pin through the RAW voltage regulator input to reduce it to 3.3V is one possible fix. This worked for me as well, albeit it does make programming a little less practicaL.

Low power:Arduino Pro Mini advantage:s

The fact that these boards consume a lot less power than an Arduino Uno is another advantage of utilizing one of them, in addition to their low price and small size. The Uno requires 47mA when executing a blank program, as explained in this article on the power and sleep of an Arduino. Under those circumstances, the Arduino Pro Mini 5V uses 16mA, or slightly over a third of that amount.

each using the “Blink” design for this article and discovered that each fluctuated between:

·      5V board @ 5V input            Current: 18mA & 26mA      Power: .09W & .013W

·      3.3V @ 3.3V input                 Current: 4mA & 8mA          Power: .0132W & .0264W

Thus, the 3.3V version uses less than 25% of the current of the 5V version when the LED is off. If power is defined as voltage times current, then the low value for a 5V board is.018A x 5V, which equals.09W, while the low value for a 3.3V board is.004A x 3.3V, which equals.0132W. This means that the 5V version uses 6.8 times as much power as its 3.3V equivalent during the low power cycle (probably when the LED is off).

Although switching from 5V to 3.3V can bring some challenges, the reduced voltage might be well worth it for battery-powered applications. Furthermore, the 3.3V version’s RAW input makes it simple to connect a 3.7V LiPo battery, but the 5V version is, at best, dubious.

I also performed some power tests on the voltage converter, using the same blink sketch, to see if you’re using it to reduce inputs to a usable level:

·      5V board @ 9V input            Current: 16.75mA & 25.0mA          Power: .15W & .225W

·      3.3V board @9V input          Current: 3.9mA & 7.6mA                Power: .035W & .068W

Despite the fact that current values are essentially similar to applying the correct voltage directly to the 5V and 3.3V pins, keep in mind that the voltages have been boosted, which reduces the efficiency of the total power input. Of course, if low-power design is truly important to you, you should read the power/sleep page linked above for some additional tips and tactics.

3.3V and 5V Arduino Pro Mini differences

The debate between 5V and 3.3V is somewhat irrelevant if you don’t know what kind of board you have. The simplest way to determine this is to check the rating box on the back, as seen below:

This is hand-marked, which is unfortunate because it might have worn off. Check out the voltage regulator if you require more assurance. The 3.3V version here says “KB33,” and the 5V version says “KB50,” however it’s certainly feasible that various boards may utilize different components. The oscillators are also marked differently, though the significance is less clear.