How to Power a Raspberry Pi Pico
There’s more than one way to power a Raspberry Pi Pico microcontroller board, depending on your particular project needs.
The Raspberry Pi Pico is the only microcontroller board made by the Raspberry Pi company. Similar to products like Arduino and ESP-32, the Pico was designed to control electronic components and is much better suited for running simple tasks in basic electronics projects than a full-fledged Raspberry Pi computer.
There are a few different ways in which you can power a Pico, as we will explore here.
The Raspberry Pi Pico is a minimal, low-cost, and high-performance microcontroller board built around the RP2040 chip. The RP2040 is an in-house microcontroller chip from Raspberry Pi Ltd. and is responsible for powering several other RP2040-based boards, besides the Pico.
The Raspberry Pi Pico is the company’s official RP2040 board and comes with 2MB of on-board QSPI flash memory for writing and loading code. It has 40 pins in total for interfacing with other electronic components, 26 of which are multifunction GPIO pins. Check out the Raspberry Pi Pico’s pinout in detail.
There are several versions of the Raspberry Pi Pico board: the standard Pico (with unpopulated pin holes), the Pico H (with pin headers pre-soldered), the Raspberry Pi Pico W (with Wi-Fi and Bluetooth), and the Pico WH (with both wireless connectivity and pre-soldered headers).
Compared to Raspberry Pi single-board computer models, the Pico has a relatively low power drain, and it is capable of operating with a voltage supply in the range of 1.8V and 5.5V DC. This allows it to be run from the 5V USB port on a computer or a pair of AA batteries and allows users flexibility with their choice of power supply. The Pico can be fed power through the micro-USB port on the board or GPIO pin 39 (VSYS).
The most straightforward way to power a Raspberry Pi Pico is to connect the micro-USB port to your laptop, desktop, or Raspberry Pi computer using a micro-USB to USB cable. The USB cable will provide the Pico with the power it needs. The computer has to be powered on for it to work.
You'll need to connect your Pico to a computer the first time you use it so that you can install the MicroPython firmware, and afterward to program the microcontroller. Be sure to use a USB data cable and not a charge-only cable to connect the Pico to your computer. It is not the most portable setup and could be temporary until you find a battery pack or portable power supply.
You can also connect the Raspberry Pi Pico to the mains with a compatible cable and an AC to USB adapter. You need to take extra care when choosing a power supply, as an incompatible one may risk damaging your Pico. The cable and adapter should not deliver more than the maximum voltage of 5.5V to the Pico.
This setup removes the need to have another computer connected to operate your Pico, since the board will automatically run a program saved with the name main.py when you power it up. It doesn't however make for a very portable setup, so consider one of the next options if portability is a primary concern of yours.
If you want to power the Pico using a battery, you can use a battery pack or a set of AA or AAA batteries. A single Li-ion battery will also work well for this purpose. To do this, you must connect the batteries to the VSYS pin and the GND pin on the Pico.
To power the Pico with AA batteries, you need a two- or three-cell battery pack, two jumper leads with sockets, and heat-shrink tubing. You can find a detailed tutorial on the Raspberry Pi website.
It involves some wire stripping and soldering. At the end, you should have a battery pack you can connect to the VSYS and GND pins. The ground wire keeps you and the Pico protected in the event of a short circuit. You should not use more than three AA alkaline batteries or four rechargeable NiMH or NiCad batteries to power the Raspberry Pi Pico, as this may cause overvoltage and permanently damage the Pico.
If you'd rather not do any wiring, you can use the Pico-UPS-A module from Waveshare to power your Raspberry Pi Pico. It mounts on top of the Pico and features a Li-ion battery switching charger with power path management, and a voltage/current monitoring chip that allows battery monitoring in real-time. It supports a 14500 Li-ion battery with a capacity of up to 800mAh, which should power the Pico for 10 hours or more.
Advantages of using batteries to power the Pico include portability and low cost. However, the output voltage may vary as the batteries start to drain, affecting the Pico's performance.
Alternatively, you can use a USB battery pack to power your Raspberry Pi Pico. In this case, you will need to use an always-on battery pack or add an LED indicator or another component to increase the current draw.
This is because battery packs automatically switch off when a certain minimum amount of current (usually about 100 milliamps) isn’t being drawn from them, and the Pico will typically use much less than that.
It is also possible to power the Raspberry Pi Pico with a solar panel as long as you ensure that the Pico is getting the correct voltage and current. You’ll need a solar panel that is capable of 5V output, a battery charge controller, and a DC/DC converter to step up the voltage from the controller.
The Raspberry Pi Pico is a very flexible device with a wide voltage rating to accommodate various power supplies. As always, keeping safety and power requirements in mind is essential when experimenting with different power supplies. The power source you choose will depend on the tools you have available along with your project demands.
Tomisin is a staff writer at MUO with a penchant for breaking down complex topics into easily digestible bits. He first started writing reviews of phones and gadgets in 2016 and loves reading spec sheets and tinkering with new technology.Currently, he writes about DIY tech for MakeUseOf and looks forward to expanding his horizons.main.py