2 layers94.1 × 85.5 mm Maatherboard, the printed circuit board in 3D

Maatherboard

A single-sided PCB controller motherboard designed for an environmental test chamber (CryoFrost) driven by an ESP32, featuring precision temperature/humidity control, thermoelectric Peltier cooling, ultrasonic…

Open in PCBKit

Size: 94.1 × 85.5 mm
Copper layers: 2
Thickness: 1.6 mm
Parts: 44
Nets: 47
Pads: 134
Tracks, vias: 249, 0
Pours: 1
Routed: Yes
KiCad: KiCad 10.0 (file 20260206)
Created: 18 Oct 2026
Updated: 18 Oct 2026

Overview

Maatherboard is an open-source printed circuit board by wwwansarmhd2-ctrl, from the wwwansarmhd2-ctrl/Cryofrost-PCB repository on GitHub. It is a 2-layer board of 94.1 × 85.5 mm with 44 parts on 47 nets, routed with 249 tracks and 0 vias.

It is built around the IRLZ44N and PN2222A. Its parts include 13 resistors, 6 transistors, 3 connectors, 2 diodes and 2 switches. It belongs with the ESP32 boards of this library.

Main components

README

README.md

CryoFrost Chamber Controller Motherboard

PCB 3D Render

📄 View Complete Schematic PDF

🛠️ Hardware Specifications

Microcontroller: ESP32 NodeMCU Development Board (30-pin, ESP-WROOM-32)
Power Input: 12V DC via 5.08mm screw terminals (powersupply1 & powersupply2)
Regulated Logic Power: 5V DC via on-board LM2596 / Mini360 step-down buck converter module
Peltier Relay (K1): 5V DC SPDT relay (Songle SRD-05VDC-SL-C) switched via PN2222A BJT driver
Humidifier Relay (K2): 5V DC SPDT relay (Songle SRD-05VDC-SL-C) switched via PN2222A BJT driver
Fan 1 (Heatsink Exhaust): 12V PWM-controlled via IRLZ44N N-Channel MOSFET + BC547 pre-driver
Fan 4 (Chamber Circulation): 12V PWM-controlled via IRLZ44N N-Channel MOSFET + BC547 pre-driver
Constant Fans (Fan 2 & Fan 3): Direct 12V power rails
I2C Bus 1: Primary Chamber Sensor (BME280 / SHT31) + 128x64 OLED Display (SSD1306 / SH1106)
I2C Bus 2 / Auxiliary: Secondary Sensor connector (J1) for DHT22 / DS18B20 / SHT31

📌 ESP32 Pin Mapping

Pin / Function	ESP32 GPIO	Description
Peltier Relay	GPIO 25	Low-side NPN driver with 10kΩ pull-down failsafe
Humidifier Relay	GPIO 33	Low-side NPN driver with 330Ω base drive
Fan 1 PWM	GPIO 13	Inverted PWM (BJT pre-driver to IRLZ44N Gate)
Fan 2 PWM	GPIO 23	Inverted PWM (BJT pre-driver to IRLZ44N Gate)
Display I2C SDA	GPIO 22	OLED Display Data
Display I2C SCL	GPIO 21	OLED Display Clock
Sensor I2C SDA	GPIO 18	SHT31 Secondary I2C Data
Sensor I2C SCL	GPIO 19	SHT31 Secondary I2C Clock

📦 Files in this Repository

maatherboard.kicad_sch - KiCad 10 Schematic Source
maatherboard.kicad_pcb - KiCad 10 PCB Layout (optimized for single-sided CNC isolation milling)
schematic.pdf - High-resolution printable schematic PDF
pcb_render.png - 3D board rendering
Gerber_files/ - Exported CNC isolation milling & drill files
MY LIB.pretty/ - Custom footprint library

📄 License

Open source hardware design.

Parts

Qty	Value	Footprint	References
6	F1	MY LIB:TerminalBlock_Xinya_XY308-2.54-2P_1x02_P2.54mm_Horizontal	FAN1, FAN2, FAN3, FAN4, pump1, Pump1
4	1K	MY LIB:resistor	R13, R14, R16, R18
4	4.7k	MY LIB:resistor	R6, R7, R8, R9
2	10K	MY LIB:resistor	R17, R22
2	330	MY LIB:resistor	R12, R23
2	BC413	TerminalBlock:TerminalBlock_Xinya_XY308-2.54-3P_1x03_P2.54mm_Horizontal	Q4, Q6
2	D	MY LIB:R_Axial_DIN0204_L3.6mm_D1.6mm_P5.08mm_Horizontal	D2, D4
2	IRLZ44N	MY LIB:TO-220-3_Vertical	Q3, Q5
2	JQC-3FF-005-1Z	Relay_THT:Relay_SPDT_Hongfa_JQC-3FF_0XX-1Z	K1, K2
2	PN2222A	TerminalBlock:TerminalBlock_Xinya_XY308-2.54-3P_1x03_P2.54mm_Horizontal	Q1, Q2
1	+ve	TerminalBlock_Phoenix:TerminalBlock_Phoenix_MKDS-1,5-3-5.08_1x03_P5.08mm_Horizontal	powersupply1
1	-ve	TerminalBlock_Phoenix:TerminalBlock_Phoenix_MKDS-1,5-3-5.08_1x03_P5.08mm_Horizontal	powersupply2
1	10k	MY LIB:resistor	R21
1	Conn_01x01_Pin	Connector_Pin:Pin_D1.2mm_L10.2mm_W2.9mm_FlatFork	PELTIER1
1	Conn_02x02_Counter_Clockwise	MY LIB:Buck converter	Buckconverter1
1	Display	MY LIB:TerminalBlock_Xinya_XY308-2.54-4P_1x04_P2.54mm_Horizontal	DISP1
1	ESP32	MY LIB:ESP32 MYKIT	J2
1	GND	MY LIB:TerminalBlock_Xinya_XY308-2.54-2P_1x02_P2.54mm_Horizontal	gnd1
1	HUM	MY LIB:TerminalBlock_Xinya_XY308-2.54-2P_1x02_P2.54mm_Horizontal	Hum1
1	SENSOR	MY LIB:TerminalBlock_Xinya_XY308-2.54-4P_1x04_P2.54mm_Horizontal	SENSOR1
1	sensor 2	MY LIB:TerminalBlock_Xinya_XY308-2.54-4P_1x04_P2.54mm_Horizontal	J1
1	shifter	TerminalBlock:TerminalBlock_Xinya_XY308-2.54-3P_1x03_P2.54mm_Horizontal	J3

The 40 most common of 44 parts.

Questions

How big is the Maatherboard PCB?

It measures 94.1 × 85.5 mm and has 2 copper layers, 1.6 mm thick.

What parts does the Maatherboard use?

44 parts, built around the IRLZ44N and PN2222A. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.

Where can I download the Maatherboard KiCad files?

From the wwwansarmhd2-ctrl/Cryofrost-PCB repository on GitHub, at the commit this page was made from: the board is maatherboard.kicad_pcb and its schematic maatherboard.kicad_sch. PCBKit opens the board in the browser, with nothing to install.

Can I use the Maatherboard design in my own project?

Its repository states no licence, so its author keeps all rights: ask wwwansarmhd2-ctrl before reusing the design.

Category and platform

ESP32

Project files

Show this board on your page

A live frame, for any web page

<iframe src="https://pcbkit.io/embed/boards/wwwansarmhd2-ctrl-cryofrost-pcb" title="Maatherboard in PCBKit" width="100%" height="480" style="border:0;border-radius:12px" allow="fullscreen" loading="lazy"></iframe>

A picture

<img src="https://pcbkit.io/embed/boards/wwwansarmhd2-ctrl-cryofrost-pcb.jpg" alt="Maatherboard" width="1200" height="900">

A picture that opens the board, for a README

[![Maatherboard](https://pcbkit.io/embed/boards/wwwansarmhd2-ctrl-cryofrost-pcb.jpg?size=s)](https://pcbkit.io/boards/wwwansarmhd2-ctrl-cryofrost-pcb)

Source

Repository: wwwansarmhd2-ctrl/Cryofrost-PCB
Board file: maatherboard.kicad_pcb
Commit: 71fc230
Licence: Not stated

Similar boards

2 layers67.4 × 42 mm
FlipperZeroModule
ComplacencyKillz/GhostMesh
Meshtastic + Flipper Zero integration for offline red team comms — remote Bad USB, killswitch, and mesh-based C2 over LoRa
23 parts5MIT
2 layers80 × 120 mm
Mppt arduino
anupam-dubey/Solar-MPPT-Charge-Controller
Arduino SOlar MPPT chrage controller
34 parts
2 layers148 × 85.2 mm
Thesis KiCad
drewsix9/Thesis_KiCad

24 parts
2 layers131 × 125 mm
Industry temperature control
IaMdEvJaXoN/industry_temperature_control_system
This project entails Dallas Temperature sensors sending data to the ESP32 which then determines the PWM output to the actuators after the PID engine runs.The ESP32 also sends telemetry to Firebase RTDB which then sends…
32 parts
2 layers64 × 50 mm
Spectre tht
mkrmx/spectre
Sensor de iluminación por medio de Hall + LDR
51 partsMIT
4 layers99.5 × 76.7 mm
ROCKET
Pingu207/ROCKET
Designing and building a TVC rocket controlled by a custom PCB wired to a ESP32-WROOM board
113 parts
2 layers80 × 60 mm
UQS Theseus HARVEST Control Boad
yoganshbhalla/payl_theseus_2026_HW
Repository containing all Payload PCBs and FW for Theseus 2026
58 parts
2 layers152.4 × 101.6 mm
8088-FE2010A SBC
skiselev/micro_8088
Micro 8088 - IBM XT Compatible Processor Board based on Faraday FE2010 chipset
72 parts412GPL-3.0