This is a 3D-printed plastic case specifically designed for Raspberry Pi Pico W microcontrollers with straight pin headers. It is one of the products in the IoT Case Lab (aka ICL) line of cases.

The design of the case model was conceived and developed to make the controller convenient to use, minimizing the time spent on assembly and connecting the rest of the project components.

If your Raspberry Pi Pico W has side-mounted pin headers, we recommend considering another ICL-made case (ICL_RPIPW_SI_V1), which is designed specifically for this pin configuration.

Who needs it

This case is suitable for use in DIY projects that use the popular Raspberry Pi Pico W microcontroller (the green board with the micro USB connector, from 2022).

Radio amateurs and DIY enthusiasts who need to conveniently connect project components to the RPi Pico W controller will find this case simple and easy to install and use, especially for connecting companion components with cable harnesses (Dupont-style connectors).

We hope to see both beginners and professionals in the ICL case line’s user base, including those involved in designing and building smart devices and home automation. The case should also appeal to those who spend a lot of time in a lab: students and teachers, testers, programmers, and those creating educational materials or running a technical blog.

Why did you make it?

In the DIY field, there is a wide variety of microcontroller boards based on popular hardware platforms like Arduino, ESP8266, ESP32, and Raspberry Pi Pico.

All of these controllers are sold as “Dev Boards,” which come with pre-soldered straight pin headers. This format is most often used with Dupont connectors to connect components to the controller.

Pin headers on the main controller board are a very convenient way to quickly connect and disconnect components in a project, especially for users who don’t want to solder.

However, there is a significant drawback: Dupont connectors often don’t stay in place well. This can lead to a poor connection at best, and frequent disconnections between components at worst. This is very frustrating, especially when a project has many connections or is built in a limited space.

When developing this product, ICL aimed to solve several problems at once:

• Allow the use of Dupont connectors while securely fastening them to the pin headers.
• Protect the controller board with a plastic case to prevent accidental short circuits from various metal surfaces.
• Securely hold the controller in place.
• Create a well-designed case for the standard controller module.
• Provide the ability to connect (combine) cases of various sizes, layouts, and purposes for project components.

What makes it special?

• Designed specifically for the Raspberry Pi Pico W controller.
• The panel securely fastens the Dupont connectors in place.
• All pin headers on the controller board are accessible for connections.
• The controller is secured inside the case using the four standard mounting holes on the RPi Pico W board.
• The BOOTSEL button is accessible through a hole in the case.
• The case has its own external mounting tabs.
• Although not originally intended, the internal space of the case also allows for the installation of pin headers for the DEBUG port (SWDIO, GND, SWCLK).
• Features special ICL Square Finger Joints – universal inter-case connectors – that are equipped on all IoT Case Lab products.
• Ventilation holes are located on three sides: two side faces and the top of the case, to provide passive cooling.

What’s in the box, assembly, and installation

Product includes:

Case – 1 pc;

Button cap – 1 pc;

Case panel – 1 pc;

Note. Screws, bolts, and nuts are not included with the product. The Raspberry Pi Pico W controller board is not included.

Case weight (plastic parts): 25.12 g

Material: PLA plastic

Color: The color matches the photo. The shade may vary slightly from batch to batch and is not dependent on the manufacturer.

Required skills, parts, and tools:

• No special skills or experience required.
• Screwdriver.
• Screws for securing the controller board — 4 pcs.
• Screws with nuts for securing the bottom cover and mounting the case to a surface — 4 pcs.

Assembly steps:

1. Flip the case upside down (the side with the ventilation and button hole).
2. Using tweezers, place the button cap in its designated spot from the inside.
3. Insert the controller board, chip-side down (pin headers up), into its place. The micro USB connector should go into its opening first, and then the rest of the board should rest on the internal mounting posts.
4. Secure the controller board with four screws inside the case, ensuring the button cap functions correctly in its hole.
5. Install the necessary cable connectors onto the controller’s pin headers so that they lie along both long sides of the case.
6. Close the bottom opening of the case with the corresponding panel.
7. Flip the entire assembly into a normal position and, if needed, attach the case to a surface using the mounting tabs. Alternatively, use the mounting tabs to secure the bottom panel you’ve just installed.

3D Model Source Files

We have not yet implemented the ability to purchase 3D model files as a virtual product, but we plan to do so in the future.

There is a model of the case’s external contours on GitHub for customers to evaluate the dimensions and the case’s projection on the X, Y, and Z planes.

System digital serial bus I2C due to the simplicity, high enough speed, and reliability of data transmission over relatively long distances – has a high rating of use in industrial components, modules and devices, and DIY projects.

The I2C bus also allows hot connection/disconnection of slave devices and identification of devices by addresses, or unique internal register data. The bus topology and at least 7-bit addressing allow up to a hundred slave devices to be connected to the I2C network simultaneously.

All this allows to build a convenient, reliable, and functional infrastructure of sensors and actuators around the main controller.

The main controller, however, usually has only one I2C interface and/or a limited number of free pins. That is why, in order to fully use the I2C bus in the development and operation, interface splitters are used. And then through the splitter connect to the main controller the required number of sub-components.

The offered device is specially designed for such tasks – I2CHUB_V1 – splitter and converter of interface connector types in one module.

The I2CHUB module will be useful for:

• Creating prototypes of electronic devices with a large number of connected modules via the I2C bus, which, traditionally for Arduino, are connected to the system by cables with pin connectors from Dupont, JST, or others with a pin-to-pin step of 2.54 mm;.
• Construction of DIY devices with a large number of modules connected by the I2C bus;
• Remotely distanced groups of modules or devices, such as weather stations with remote cable groups of sensors.

On the module, as one of the delivery options of the User’s choice, it is possible to install six connectors (4 pins 2.54) with I2C interface and two connectors (2 pins 2.54) for the power supply. The User can also add the required number of appropriate interface cables to the kit when ordering.

Description

The I2CHUB interface splitter module is a passive device and allows you to connect several (up to five) devices (sensors or actuators) to the main controller at the same time. The controller and splitter form a network of connected I2C devices with a bus-type topology and Master-Slave interaction profile.

Also, if you install different connectors (JST and/or Dupont) on the board of the splitter module, I2CHUB will also act as a converter of physical interfaces, which is very convenient for prototyping and development.

Multiple I2CHUB devices can be freely cascaded within the limits allowed by the I2C bus specification, and further, expand the total number of free ports in the network of subordinate smart devices of the master controller.

Connection

The main controller which will work in the “Master mode” is connected to one of the 4-pin ports of the module. Subordinate devices are connected to other 4-pin ports. In this scheme, all devices are powered by the main controller, and the 2-pin power connectors on the I2CHUB module board are not involved.

Power connectors can only be used if each of the devices on the bus is powered from its own source.

For example, the main controller can feed only itself and then only the interface signals are connected to the splitter: SDA, SCL, GND – without power, but with a common “ground” signal for all devices on the bus.

In this case, slave devices connected to the I2CHUB splitter must be powered directly from it:

• power to the I2CHUB is supplied via two-pin connectors;
• power from the I2CHUB to each device is supplied through the appropriate 4-pin interfaces;
• keep in mind that the controller is powered by itself.

WARNING! Be careful when designing – do not allow the current to run on the bus from multiple power sources – the devices on the bus will be damaged under the counter-current impact.

If you want to use an additional I2CHUB splitter, then instead of one of the slave devices you may connect an additional splitter, and then connect to it other devices that do not have enough free ports on the first splitter.

Recipe application as an example

To build a personal weather station, it is necessary to connect a number of sensors to the controller to measure ionizing radiation, ultraviolet light, temperature, atmospheric pressure, relative humidity, and to detect lightning strikes.

The Bill of Materials, in this case, it is possible to make as the following:

• MSU: ESP12.OLED module based on ESP8266 and OLED SSD1306, I2C;
• I2C Splitter: I2CHUB 1-to-5 I2C bus passive hub;
• user interface module: I2CUI4_V1, I2C;
• ionizing radiation sensor: GGreg20_V3, discrete pulse output;
• ultraviolet sensor: VEML6075, I2C;
• CO2 sensor: CCS811, eCO2 & eTVOC, I2C;
• temperature, atmospheric pressure, humidity sensor: BME280, I2C;
• Lightning detector: AS3935, I2C.

As we can see in this example, with a fairly wide functionality of the weather station, only one I2CHUB splitter will be enough to connect via I2C bus all the sensors listed to the main controller.

Moreover, if it is necessary to expand the weather station with new sensors (for example, add a light sensor: MAX44009, I2C), it will be easy to do just by using one more splitter. In this scenario, we get 4 more free I2C ports.

Product delivery kits.

1. Basic Kit:

• I2CHUB_V1 module board without connectors.

Note: The user can install his own 2.54 mm connectors on such a board

Technical description: i2chub_v1-product-description-and-datasheet-ukr, i2chub_v1-product-description-and-datasheet-eng.

Dimensions

The module board has the following linear dimensions:

• X: 53 mm;
• Y: 18 mm;
• Z:< 15 mm with connectors.

Dimensions along the axes of the mounting holes:

• X: 48 mm;
• Y: 12 mm.
• Holes: 2 x d3 mm.

References

Manufacturer message

Dear Reader! Thank you for your interest in our products. We hope that you enjoy this device. IoT-devices was born thanks to the support of our customers and thanks to our experience and love for Electronics.

Designed and made by IoT-devices with freedom & wisdom in Ukraine – 2021. All rights reserved.

Compatible with ARDUINO, ESP12.OLED_V1 controllers, NodeMCU board (based on ESP8266-12), modules on the ESP8266EX, ESP32 or other chip, which are powered by a voltage in the range from 1.8 to 5.5 V.

Functionality

The module connects to the main controller via a 4-wire I2C bus interface and provides the following functions:

• Data entry with a five-button keyboard (left, right, down, up, OK)
• Data output to RGB LED;
• Output of sound sequences to the active indicator of the buzzer type;
• I2C bus input and output through ports. Input for connection to MCU and output – for connection of any external devices that support the I2C specification.

Thanks to the use of the I2C bus and the MCP23017 port expander, GPIO savings of the main controller and the ability to input and output information in a user-friendly way are achieved. The rest of 7 GPIOs are connected to separate pin connectors for additional I / O signals connection according to the user’s design.

Int A & Int B output signals are available – can be used for interrupt processing when the state of the module inputs changes.

Application

I2CUI4_V1 will be convenient to use as a control panel and status display in user devices:

• electronic clocks,
• radiation level dosimeters,
• smart outlets,
• thermostats,
• multimedia and audio devices,
• weather stations and others.

Compatibility

Compatible with controllers and platforms:

• ARDUINO,
• ESP12.OLED_V1,
• NodeMCU board (based on ESP8266-12),
• modules on the ESP8266EX chip,
• ESP32,
• or others powered by 1.8 – 5.5 V;
• integration into Home Assistant (with ESP Home plugin), Blynk, OpenHab, Node-RED, Tasmota is possible.

Minor and major versions of the module

Unlike the minor version I2CUI3_V1, the I2CUI4_V1 user interface module uses a widely supported 16-bit MCP23017 port expander. This makes it possible to use this module in devices for integration into Home Assistant, Arduino and many others.

Chips of user interface modules:

• I2CUI3_V1 – 8-bit, I2C, PCA9538, 2^3 GPIOs;
• I2CUI4_V1 – 16-bit, I2C, MCP23017, 2^4 GPIOs.

The major version of I2CUI4_V1 has the following features:

• single digital interface – 2 x I2C (input / output) ports;
• 5 “joystick” buttons; sound indicator; RGB LED indicator;
• selection of one of 8 module addresses on the I2C bus via solred-pads;
• 7 free GPIOs are connected to separate pin connectors.

Driver-level support

Support for the MCP23017 chip at the driver level is stated in particular by the following platforms:

Assignment of module ports

Power supply and consumption

Power supply of the module is possible in the range of voltages of 1,8 – 5,5 volts. The current consumption of the I2CUI4 module at rest is about 1 microampere. In the case of simultaneous data output to R + G + B + buzzer, the maximum current consumption can reach 20 milliamperes.

Addressing on the I2C bus

The address of the module has a fixed and variable part:

The address of the module I2CUI4_V1 is selected in accordance with the documentation on the chip MCP23017, because it is this chip of the module that interacts with the main controller via the I2C bus.

Interrupt handling

The module has two interrupt channels: Int A and Int B. All processing and logic (active-low) corresponds to the documentation for the MCP23017 chip. Interrupt processing is provided for the master controller to monitor changes in GPIO states set to input mode.

According to the design of the interface module I2CUI4_V1, input mode:

• must be set for:
  • GPIO 11 (GPA3) – Key Up on board
  • GPIO 12 (GPA4) – Key Down on board
  • GPIO 13 (GPA5) – Key Left on board
  • GPIO 14 (GPA6) – Key Right on board
  • GPIO 15 (GPA7) – Key OK on board
• can be set for spare GPIO ports if used by the user as inputs: GPIO 1 (GPB1), GPIO 2 (GPB2), GPIO 3 (GPB3), GPIO 4 (GPB4), GPIO 5 (GPB5), GPIO 6 (GPB6) ), GPIO 7 (GPB7).

Ports GPIO 0 (GPB0) Buzzer on board, GPIO 8 (GPA0) LED – Blue on board, GPIO 9 (GPA1) LED – Green on board, GPIO 10 (GPA2) LED – Red on board – work on the module as outputs.

Module dimensions

• Dimensions of the module board 50 x 52 mm,
• Module height (Z): 15 mm.

Product kit sets

The module is delivered in the following sets:

• Basic set:
  • 1 pc – I2CUI4_V1 user interface module;
  • PCB Headers ( Dupont Headers ) 2,54 20p – 1 pc.

• Basic + Connectors set: (Note: The user receives the module with installed connectors )
  • 1 pc – Basic set;
  • Connectors:
    • JST XH 2,54 2p – 1 pc:
    • JST XH 2,54 4p – 4 pcs..

• Basic + Connectors + Cables set: (Note: The user receives a module with installed connectors )
  • 1 pc – Basic + Connectors set;
  • Cables:
    • JST XH 2,54 4p – JST XH 2,54 4p – 1 pc.
    • JST XH 2,54 2p – JST XH 2,54 2p – 1 pc.
    • JST XH 2,54 4p – Dupont 4p – 1 pc.
    • JST XH 2,54 2p – Dupont 2p – 1 pc.

Technical description: i2cui4_v1-product-description-ukr, i2cui4_v1-product-description-eng.

References

The port expander chip used in the module:

Manufacturer message

Dear Reader! Thank you for your interest in our products. We hope that you enjoy this device. IoT-devices was born thanks to the support of our customers and thanks to our experience and love for Electronics.

Designed and made by IoT-devices with freedom & wisdom in Ukraine – 2021. All rights reserved.

Purpose and compatibility

PS4IoT is an uninterruptible power supply module with battery charging and protection, for building smart devices with power paths’ redundancy, with 3.0 to 6 volts and 3V3, 5V or 12V output voltages, with total power up to 5 watts.

The module is designed for use in electronic devices based on any microcontroller platform, such as ESP8266, ESP32, Arduino, STM32, and derivative boards ( ESP12.OLED, NodeMCU, etc.) as an autonomous or software-controlled power supply unit.

Features

• Start from AC/DC adapter when the battery is deeply discharged;
• Start from AC/DC adapter when there is no battery;
• Automatic battery charging and simultaneous use of the device;
• Possibility to replace the battery without interrupting power from the AC/DC adapter;
• When powered by the AC/DC adapter, the battery is not connected to the load, which saves the number of charge-discharge cycles (prolongs battery life).

Capabilities of the module with basic settings

This tiny module may surprise you with many important and interesting functions. PS4IoT_V1 with basic settings provides:

• Automatic online switching “battery-mains” and vice versa, without interruption of output voltage generation (12V, 5V, 3V3) of loads;
• Automatically switches to AC/DC adapter 5V when the battery is disconnected without interrupting power to the loads;
• Automatic battery charge/discharge control; Default charge current is set to 0.5 A. The state of the battery charging process is displayed by two LED indicators.

Module application profiles

The module can provide the following profiles for autonomous and controlled use as part of a smart device:

• a battery-free device powered only by an AC/DC 5V adapter;
• a device powered by Li-Ion battery and AC/DC adapter 5V
• a device with rechargeable Li-Ion battery only;
• a device with fault-tolerant redundancy of 3 power supply paths.

Smart power supply module formula

Online Uninterruptible Power Supply Unit module

• With automatic charger and selectable power source;
• Intelligent and connected;
• With power source redundancy layout;
• Fully autonomous or sufficiently managed;
• With or without a battery;
• For pockets or stationary;
• With simultaneous charging and power supply of load;
• Indoor or outdoor;
• In inexpensive and miniature design;
• Best suited for smart devices and IoT;

As you can see from our “formula”, you can simultaneously power one or more payloads, connect a controller with any functionality to the module according to your design idea – in other words, you can create the most demanding portable and stationary devices using the PS4IoT_V1 module.

This module is a versatile component that will provide reliable power, observability and controllability for your DIY or even commercial product.

PS4IoT acts as an intelligent intermediary between the load and all available power sources.

This power supply automatically protects the device and the battery, providing consumers with the ease and simplicity of using the end device in a way that is only found in high-quality and high-tech smartphones.

Module functions

Battery protection and safety functions

Module block diagram

Software monitoring of Li-Ion battery charging status

PS4IoT_V1 has a number of signal lines that allow the main controller to monitor the charging process status, temperature, and battery voltage programmatically. For example, if a mismatch is detected, such as exceeding the charging time or battery temperature, the controller can programmatically stop or restore the charging process. In addition, these mechanisms in combination with the sleep mode are reasonable to use in the charge/discharge control software algorithm to extend battery life.

Note. What if we make two interfaces at once on the GGreg20 module: pulse output and I2C? This would be very convenient, but the clients’ costs increase unnecessarily in that case. The companion controller occupies a certain area on the module board. The I2C bus occupies twice as many controller ports as the pulse output. All that adds significantly to the unit price. On the other hand, the pulse counting output interface takes up only one controller GPIO with an interrupt handler and is much easier to code. The current version of the GGreg20 module can work without a controller at all: a user can use a watch to monitor the duration of the radiation measurement and count led blinks manually. The PS4IoT_V1 version of the module does not support connecting an NTC battery thermistor directly to the charging controller. Therefore, temperature monitoring can be implemented by connecting an additional temperature sensor to the main controller using I2C bus or other interfaces such as 1-Wire, SPI, NTC-thermistor, etc. Thus, through the Charge Enable signal (see CEset.2) the controller can prohibit or allow charging depending on the battery temperature.

The interfaces are located on one side of the module

It is recommended to design the case of the device where you plan to install PS4IoT_V1 so that the bottom edge of the PS4IoT module board touches one of the outer sides of the case, as shown in the pictures. In that case

• Charge control LED;
• Power supply input 1 (μUSB);
• ON/OFF main switch;
• Aux spare interface – the connector for external devices;

can be used to organize a convenient interface to control the entire device through the user-provided mounting holes in the housing.

Cautions

Caution! Use quality batteries to obtain the declared technical characteristics of the product.

Caution! Use quality AC/DC adapters with appropriate cables capable of withstanding 5 volts with a load of up to 2 amps.

Caution! Maximum permissible load current:

• to the output 12V – 150 mA;
• to the output 5V – 1A;
• to the output 3.3V – 1A.

!! The maximum total load on the charger and outputs is up to 5 Watts.

Delivery sets

Set №1 – only PS4IoT_V1 module (Basic)

1. PS4IoT_V1 module – 1 pc;
2. Jumper on the board – 2 pcs;
3. Pin connector 2.54 2P M, straight, included – 7 pcs;
4. Pin connector 2.54 4P M, straight, included – 3 pcs.

Set №2 – module with connectors and cables (Basic + Connectors (installed) and cables)

1. PS4IoT_V1 module – 1 pc;
2. Jumper on the board – 2 pcs;
3. Pin connector 2.54 2P M, straight, included – 7 pcs;
4. Pin connector 2.54 4P M, straight, included – 3 pcs.
5. Battery cable, flat, 15 cm, 2 wires, with connectors – 1 pc: 2P JST XH2.54 F – Dupont 2x1P F.
6. Power output cable, flat, 20 cm, 2 wires, with connectors – 2 pcs: 2P JST XH2.54 F – Dupont 2x1P F.
7. Charging status output cable CP&CC, flat, 20 cm, 2 wires, with connectors – 1 pc: 2P JST XH2.54 F – Dupont 2x1P F.
8. Battery level output cable, flat, 20 cm, 2 wires, with connectors – 1 pc. 2P JST XH2.54 F – Dupont 2x1P F.
9. JST XH 2.54 2P M connector, straight, on the board – 7 pcs;
10. JST XH 2.54 4P M connector, angled, on the board – 1 pc;
11. JST XH 2.54 4P M connector, straight, on the board – 1 pc;

Note : In this version, these connectors are soldered to the board and are ready to use with the appropriate cables.

Options № 3 – module with connectors and cables (Basic + Connectors (installed) and cables + AUX )

1. PS4IoT_V1 module – 1 pc;
2. Jumper on the board – 2 pcs;
3. Battery cable, flat, 15 cm, 2 wires, with connectors – 1 pc: 2P JST XH2.54 F – Dupont 2x1P F.
4. Power output cable, flat, 20 cm, 2 wires, with connectors – 2 pcs: 2P JST XH2.54 F – Dupont 2x1P F.
5. Charging status output cable CP&CC, flat, 20 cm, 2 wires, with connectors – 1 pc: 2P JST XH2.54 F – Dupont 2x1P F.
6. Battery level output cable, flat, 20 cm, 2 wires, with connectors – 1 pc. 2P JST XH2.54 F – Dupont 2x1P F.
7. JST XH 2.54 2P M connector, straight, on the board – 7 pcs;
8. Pin connector 2.54 2P M, straight, included – 7 pcs;
9. Pin connector 2.54 4P M, straight, included – 3 pcs.
10. JST XH 2.54 4P M connector, angled, on the board – 1 pc;
11. JST XH 2.54 4P M connector, straight, on the board – 1 pc;
12. Internal interface cable, flat, 15 cm, 4 wires, with connectors – 1 pc. 4P JST XH2.54 – Dupont 4x1P.
13. External interface cable, flat, 30 cm, 4 wires, with connectors – 1 pc. 4P JST XH2.54 – Dupont 4x1P.

Note : In this version, these connectors are soldered to the board and are ready to use with the appropriate cables.

Attention. AC/DC adapter(s), battery pack, solar panel and temperature sensor are not included.

Full technical description: PS4IoT_V1 power supply unit description UKR , PS4IoT_V1 power supply unit description ENG

Module presentation: PS4IoT_V1 quick facts