Overview

This version of the PCB based reflow plate aims to be as modular as possible to allow for many configurations and parts to be replaced. There are 5 main boards in the project:

  • MCU board

  • Power board

  • I/O board

  • Heating board

  • Backplane

Pinout

Each of these boards interconnect in order to create a fully functional reflow plate. The boards are stackable allowing for multiple boards to be added. The standard interface between the boards is shown below.

                      +----------------------+----------------------+
               5V ----+                      |                      +---- SDA
                      | LOGIC POWER          |                  I2C |
              3V3 ----+                      |                      +---- SCL
                      +----------------------+----------------------+
          SENSE A ----+                      |                      +---- TX0
                      |                      |                UART0 |
          SENSE B ----+                      |                      +---- RX0
                      |                      +----------------------+
          SENSE C ----+ TEMPERATURE SENSORS  |                      +---- TX1
                      |                      |                UART1 |
          SENSE D ----+                      |                      +---- RX1
                      |                      +----------------------+
          SENSE E ----+                      |                      +---- GPIO0
                      +----------------------+                      |
          SENSE A ----+                      |                      +---- GPIO1
                      |                      |                      |
          SENSE B ----+ CURRENT SENSING      |                      +---- GPIO2
                      |                      |                 GPIO |
          SENSE C ----+                      |                      +---- GPIO3
                      +----------------------+                      |
            RESET ----+ SYSTEM RESET         |                      +---- GPIO4
                      +----------------------+                      |
               NC ----+                      |                      +---- GPIO5
                      |                      +----------------------+
               NC ----+                      |                      +---- SCLK
                      |                      |                      |
               NC ----+                      |                      +---- MOSI
                      +----------------------+                      |
HEATER CONNECTION ----+                      |                      +---- MISO
                      | HEATER CONNECTIONS   |                      |
HEATER CONNECTION ----+                      |                      +---- SS1
                      +----------------------+                  SPI |
              12V ----+                      |                      +---- SS2
                      |                      |                      |
              12V ----+                      |                      +---- SS3
                      |                      |                      |
              12V ----+                      |                      +---- SS4
                      | PCB HEATER POWER     |                      |
              GND ----+                      |                      +---- SS5
                      |                      +----------------------+
              GND ----+                      |                      +---- GND
                      |                      |            LOGIC GND |
              GND ----+                      |                      +---- GND
                      +----------------------+----------------------+

Mechanical Specifications

In order to maintain mechanical compatibility between all boards, a specification has been created to stipulate the positioning of the inter-board connections. The headers have been set at the spacing of a standard 2.54mm breadboard allowing for easy development of custom boards without the cost of PCB manufacture.

Mechanical drawing of board

The mechanical drawing of the stackable board.