Espoir_iso

# Espoir

# Overview

Espoir is a Power over Ethernet+ (PoE+ 802.3af/at) mikroBUSTM mainboard based on the ESP32-MINI-1 microcontroller.

It reduces risk, cost, and time to market by taking care of the often more challenging aspects of designing power supply and high-speed circuits of a microcontroller board. Developers can focus on their application and get to testing and deployment quickly.

Espoir's mikroBUSTM socket provides incredible ease of use, with over 1,300 mikroBUSTM add-on boards available right away, including Connaxio's mikroShield and makroShield (coming soonTM) families.

Example applications Compatible IDEs Compatible frameworks
Smart farming Eclipse IDE Espressif's ESP-IDF
Smart lighting PlatformIO IDE Arduino
Access control Arduino IDE MicroPython
Assembly line tracking PyCharm ESPHome (soonTM)
Home automation (and many more!) Tasmota (soonTM)

# Features & Specifications

  • ESP32-MINI-1 Processor
    • Single or dual core 240 MHz
    • 520 KB SRAM
    • 4 MB flash
  • Power
    • Input: PoE+ 37 V - 57 V through the Ethernet connector, with 2,250 V isolation
    • Input: 5 V through the USB-C connector (4.6 V available through a protection diode)
    • Output: 5 V at 3 A (15 W) from PoE
    • Output: 3.3 V at 0.7 A (2.3 W) (Linear, derived from the 5 V power rail)
    • Jumper-selectable PoE Class 2, 3, and 4
    • Pi-filtered PoE input and output
    • Overload and thermal protections
  • Connectivity
    • Wifi 2.4 GHz 802.11b/g/n & integrated antenna
    • Bluetooth 4.2 BLE
    • Ethernet 10/100-BaseT (80+ mbps throughput)
    • USB 2.0 via USB-C connector (tested at 2 MBaud)
    • Full mikroBUSTM socket with two grounds, 5 V, 3.3 V and 12 IOs
    • Extension header with two grounds, four additional input only pins, and the ESP32 reset signal (unsoldered socket header included)
  • Mechanical
    • Weight: 31 g
    • Size: 50.8 x 61.0 mm2
    • PCB thickness: 1.6 mm
    • Four copper layers provide augmented thermal dissipation and electromagnetic compatibility
    • Mounting holes: 4x M2.5 / 4-40. The bottom-left hole is plated and connected to local ground.
  • Operating temperature range: -40 oC to +85 oC

# Top & Bottom Views

Espoir_top_bottom

# Pinout

Espoir_pinout Figure: Espoir's headers' pins

Table: Espoir's headers' pins mapping

Espoir's ESP32-MINI-1 mikroBUSTM socket Arduino
IO2 PWM A2 / T2 / PWM
IO4 INT A10 / T0 / INT
IO5 RST RST
IO9 RX RX1
IO10 TX TX1
IO12 MISO / SDI A15 / T5 / MISO / SDI
IO13 MOSI / SDO A14 / T4 / MOSI / SDO
IO14 SCK A16 / T6 / SCK
IO15 CS A13 / T3 / CS / SS
IO18 SCL SCL
IO23 SDA SDA
I34 - A6
I36 AN A0 / AN
I37 - A1
I38 - A2
I39 - A3

Table: Espoir's "internal" pins mapping

Espoir's ESP32-MINI-1 Signal
IO1 USB UART TX
IO3 USB UART RX
IO0 EMAC TX CLK
IO19 EMAC TXD0
IO21 EMAC TXD1
IO22 EMAC TX EN
IO25 EMAC RXD0
IO26 EMAC RXD1
IO27 EMAC RX DV
IO32 EMAC MDC
IO33 EMAC MDIO
I35 ETH PHY PME N

# Dimensions

The main dimensions of Espoir are presented here. Complete 3D models can be found in Espoir's repository on Github.

Espoir_dimensions

The connector shields and the bottom-left mounting hole are connected to the local ground. It is therefore safe (and recommended) to connect them to a metal case.

Care must be taken to leave enough spacing under the PCB to avoid accidental contact of the through-hole pins with the case. A 1 mm gap should be observed between the pins and and any conductive material to maintain proper isolation. 3 mm between the bottom of the PCB and the mounting surface is typically a good starting point.

# Safety Considerations

# Electrocution Hazard

The area around the main transformer and Ethernet jack contains parts that operate at a typical voltage of 57 V, with peak voltages above 135 V. In some situations, these voltages may cause injury or death. Avoid contact with the SMD components (top) or solder joints (bottom) during operation.

# Burn Hazard

Under constant heavy load, the area and parts around the main transformer may reach over 100 oC and cause severe burns. Avoid contact with both the top and bottom of the PCB in that region when high load conditions are expected.

# Safe Handling

An IP20 enclosure with proper ventilation is recommended to avoid accicental contact and overheating. Espoir's repository offers a 3D printable snap-on backplate that provides protection from accidental contact and good ventilation.

# Certifications

Directive Applicable standards

# Additional Resources