News: PCB development - I2C_mtrDrvr V1.0, servoDigitCtrlr, pxlBlck_multiPCB, XGZP6847_adapter and nanoPxl V1.4

At the moment I am working on a few PCB projects in which I would like to give you a little insight here. 🙂

All of the boards presented in the following have been manufactured by They support my projects and have made the boards available to me. If you are looking for a reliable PCB manufacturer with very good service, I can highly recommend 🙂

I2C_mtrDrvr V1.0

The I2C_mtrDrvr board has been lying on my desk for a while. It is part of the first experiments to simplify the control of the WinDIY mechanics a little. The following components are installed on the circuit board for this purpose.

  • DRV8830 I2C motor driver for controlling DC motors up to 1A
  • ADS1115 I2C 4x ADC
  • MCP9808 temperature sensor

A connected DC motor can be controlled with the aid of the DRV8830. I also used this driver on the first version of the control for WinDIY to be able to control the individual gear motors.

The also built-in ADS1115 4x ADC can be used to read in up to four analog voltages. The first channel of the ADC is permanently connected to the shunt of the motor lead. In this way, the current motor load can also be determined and, if necessary, switched off in the event of an overload.

The MCP9808 temperature sensor is not necessary for the actual function. This provides the temperature on the PCB via the I2C bus.

The circuit works. You should only be careful with the FAULT line of the DRV8830 that is led out via the JST-PH connection, as it should not be connected to a GPIO without a series resistor. In a new version I will also accommodate this resistor on the PCB.

I will soon provide a construction article of the I2C_mtrDrvr here on Until then you will find more information and pictures in the following paragraph.


The servoDigitCtrlr board is intended as a control board for my servoDigit project (see video).

The aim is to be able to control the 28x SG90 servos (seven per digit). The following components are installed on the circuit board for this purpose.

  • 2x PCA9685 16x port I2C PWM expander
  • 2x ADS1115 4x I2C ADC
  • LM2596S step-down converter
  • 1x WS2812 2x2mm RGB Led
  • BME280 climate sensor
  • MCP9809 temperature sensor
  • DS3232M I2C RTC
  • 2x RT9013 3.3V voltage regulators
  • ESP32-Wroom as MCU

The first prototype works. The built-in JST-XH connector can also be connected directly to the balancer connection of a 4S Lipos. So you can theoretically supply the circuit or clock via a battery. The power supply of the built-in sensors and actuators can also be controlled separately from the power supply of the ESP32 to save energy.

Below is a video and a few photos of the first prototype.


The pxlBlck_multiPCB is a very closely populated four-layer circuit board. An LED matrix of 10×10 WS2812 3.5×3.5mm LEDs can be installed on the underside.

There is space on the top for the following components.

  • DS3232M RTC
  • ESP32-Wrover-B MCU
  • ADXL345 IMU
  • MicroSD card slot
  • MPR121 touch controller for up to 12 electrodes
  • BME280 climate sensor
  • USB-C connection including ESD protection and USB-serial converter via which the MCU can be programmed
  • MAX98357 I2S DAC including Class-D amplifier
  • QWIIC connection

The board is supposed to be the new centerpiece for my pxlBlck platforms. The plan is also to play MP3 files from the built-in SD card and the class D amplifier. In addition, inputs for controlling the pxlBlock can be made via the 12 touch electrodes of the MPR121.

With the help of the QWIIC connection, other sensors and actuators with the same standard can also be connected. The board is ultimately supplied with up to 15W (5V / 3A) via the USB-C connection.


The XGZP6847_adapter board is a small adapter board that I use to build my pick and place machine.

For this purpose, two XGZP6847 air pressure sensors can be installed on the board. These are used to measure the pressure or negative pressure in the suction line for receiving the components. In this way, the machine can automatically detect whether a recording process was successful or unsuccessful.

The measured pressure is output as a voltage between 0.5 and 4.5V. These voltages can be measured directly via the JST connector. With the help of the solder jumpers on the PCB, an optionally equipped ADS1115 can also be used to measure the voltages. The I2C bus is then accessible via the JST connector.

nanoPxl V1.4

The nanoPxl V1.4 board is the fourth iteration of the nanoPxl. This is an adapter board for the WS2811 with the aid of which three 5730 LEDs can be controlled. This is intended as a stronger alternative to the well-known WS2812 LED, because I need a slightly brighter version for one of my projects.

You can find more information about this in the article Electronics – soldering nanoPxl V1.1 SMD components or in the following video and pictures.

Kommentar hinterlassen

Your email address will not be published. Erforderliche Felder sind mit * markiert