Tiny Reflow Controller V2

Description

V2 of our beloved Tiny Reflow Controller! The tiniest form factor we have ever made and now it comes with an OLED LCD display to plot the reflow curve. On top of that, we have added a USB-serial interface chip to remove the necessity of an external USB-serial adapter. Every single piece of hardware that we ship out the door here were manufactured using our very own Reflow Oven Controller Shield. And we have sold countless number of them over the years and we are glad that it help many people to start reflowing their own SMD components in a reliable and repeatable manner. Along the way, we received many feedback from users and we took those feedback seriously and incorporate them in a new all-in-one reflow oven controller. Powered by the ATmega328P coupled with the latest thermocouple sensor interface IC MAX31856 from Maxim, we managed to remove the need of an Arduino board and reduce the overall cost. We also use as much SMD parts in this revision to keep the cost low (manual soldering and left over residue cleaning is time consuming) and leaving only the terminal block on through hole version which is unavoidable. We also managed to streamline all components to run on 3.3V to further simplify the design. All you need is an external Solid State Relay (SSR) (rated accordingly to your oven), K type thermocouple (we recommend those with fiber glass or steel jacket), and an oven of course! You can now select to run a lead-free profile or leaded profile from the selection switch. The example code running the reflow process utilized a PID control provided by the awesome PID library written by Brett Beauregard. Features:

• Powered by ATmega328P
  • 3.3V at 8 MHz
  • Arduino Pro / Pro Mini 3.3V 8MHz compatible
• MAX31856 thermocouple interface
• 0.96″ 128×64 OLED LCD yellow and blue color
• 2 push button:
  • 1 to start and stop the reflow process
  • 1 to select the reflow profile (lead-free or leaded) and stored on the non-volatile EEPROM
• 1 red LED for status indication
• 1 terminal block for thermocouple type K
• 1 terminal block for driving SSR (through an NPN transistor, 5mA @ 5V output) to control heating element/oven
• 1 terminal block for driving SSR (through an NPN transistor, 5mA @ 5V output) to control fan
• 1 buzzer with transistor for loud and annoying sound
• 1 reset button
• ISP pins breakout
• Built-in USB-serial interface for firmware upload and serial interface
• Unit is powered through a microUSB connector with 500 mA resettable fuse
• Comes with extra 4 pieces of M2*5mm spacer (male-female) and 4 pieces of M2*5mm screws if you decided to mount it on the oven’s front panel
• Dimension – 27.94 mm x 50.80 mm
• FR4 TG140 PCB with immersion gold (ENIG) finish
• RoHS compliant – Yes

Documentation:

• What oven to get?
• Schematic
• Design files & firmware examples on Github
• User guide
• Oven builds by customers