TESTED WITH CR-10
Succsessfull - Use 1kOhm for R3
Additional tests are required. Need to make sure the output is reliable and stable.
I updated the circuit and did a new PCB Layout. V1.6 REV0 is the current version.
Final boards are on their way. Warning: The Pinout of the v1.6 Board has changed distinctly.
This circuit board provides ABL and Laser functionally trough a 6 wire cable to the print head. It's designed for laser modules with separate 5V PWM and 12V work voltage
It also brings down the 12V PWM signal from the part cooling fan to 5V PWM to
connect the laser module PWM/TTL port.
It provides a 12V work voltage with the ability to add a safety switch to prevent laser operation during printer start up. You can also add door switches or an emergency switch so secure the laser operation.
You can optionally connect an external power supply for the laser and ABL sensor.
The board provides an optocoupler for the ABL sensor.
All connections are provided via an 6-pin connector to the print head.
You can mount the PCB to the printer frame with 3mm bolds and headnuts near the Z stepper.
Feel free to provide a nice and snugly printable case. You can bend the LED to point upwards the PCB.
To mount the laser module to the CR-10 or Ender2 use this https://www.thingiverse.com/thing:2757972
Order @ OSHPark:
I used KiCad to draw the circuit and layout the PCB.
Prototype manufacturing with OSHPark.
Current challenge: Due to the use of a FET on the CR-10 "melzi" board the PWM signal generated by the Atmel will be transformed to a PWM-GND signal. This kind of signal can not be interpreted by the laser module. It must be transformed to a regular PWM-V signal.
I updated the schematics and add a opto-isolator to convert the PWM signal to the right one.
How to build and use
- PWR: connects to the power supply (optionally plug external 12V 2A power supply direct to the boards barrel connector)
- PWM: connects to the second 12V controlled fan port on the CR-10 board
LS Safety Switch:
- Connect safety switches. Cuts 12V work voltage from the laser if not closed.
To Print Head:
- 12V working voltage for the capacitive ABL sensor
- feeds back the ABL Sensor signal to the optocoupler
- common GND for ABL and the laser work voltage
- 5V PWM control voltage to the laser module
- a safety switchable 12V work voltage for the laser
- connects to the old mechanical endstop for safety (not needed)
- connects the ABL sensor signal to the Z endstop cable from the control box
- 1x LJC18A3-H-Z/BX
- 1x LM7805CT TO-220-3
- 12x PC817 EL817 817 DIP-4
- 1x blue LED
- 2x 680Ohm resistor
- 1x 0.1µF capacitor
- 1x 0.33µF capacitor
- 2x 3-Pin Header
- 2x Jumper
- 3x JST XH 3 angled
- 4x JST XH 2 angled
- DC barrel connector (optionally)
You can also solder directly to the pads.