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LAOS Mainboard v03 » History » Version 17

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jaap, 2012-10-01 20:47


LAOS Mainboard v0.3

Design files

The KiCAD design files for this PCB are available on Github, see https://github.com/LaosLaser/Hardware/tree/master/laos-board-rev3

For a PDF of the schematics, as well as a top view image of the board, see the attachments at the end of this page.

Bill of materials

The BOM lists all recommended components. You will need to modify this list to suit your needs. Common choices:

  • Connector types. The HPC laser uses JST connectors. Our reference design uses Phoenix connectors, they are nice but not cheap. You may omit connectors for functions you do not require.
  • The 7805 voltage regulator (U3) is not needed if you have a stable 5V power supply.
  • The pololu steppers (J8,J17,J23,J32) can be omitted if you use external steppers.
  • The TIP110 (or equivalent) transistors (Q1,Q2) and associated components can be omitted if you do not want to switch external 24V loads.
  • The CAN bus transceiver (U1) and associated components can be omitted, as the CAN bus is not in use by the firmware yet.
  • The USB connector can be omitted. USB file systems are not implemented yet in the firmware yet.
  • R2 and R3 can be omitted if you use an Ethernet connector without LEDs (one would suffice, as they both just connect to the power supply).

The Ethernet connection and the SD card are essential parts of this design.

Common parts

These parts are needed for every board, no matter the type of laser it will be used for.

Count Component RS Part No. RS Price Farnell Part No. Farnell Price Comment
1 ARM mbed LPC1768 Module 703-9238 € 49,53 1761179 €49,73 Mbed
1 Hirose DM1B-DSF-PEJ 685-0788 € 2,22 1764373 €2,65 reverse SD Memory Card connector
2 DIL socket,0.3in pitch, 16 pin 402-771 € 0,18 1077315 €2,17
2 Harwin M20-7832046 681-6851 € 5,31 9688862 € 7,07 Mbed Footprint
1 MAGJACK SI-60002-F 741-8477 € 4,38 1137981 €6,27 Network connector (with LEDs: Farnell:1137983)
2 IC KB847 619-2026 € 1,96 2001656 €1,37 (5 pcs min)
1 2GB SD card 539-7804 € 9,40 SD Card (cheaper at Mycom: € 4,99)
1 100R resistor 707-7587 € 0,02
1 120R resistor 707-7599 € 0,02
4 330R resistor 707-7622 € 0,02
15 1K resistor 707-7666 € 0,02
2 2K2 resistor 707-7690 € 0,02
11 10K resistor 707-7745 € 0,02
5 100nF capacitor 721-5240 € 0,07
1 22nF capacitor 721-5268 € 0,12
1 100 µF capacitor (ELCO) 520-0996 € 0,28 min. voltage: 12V
1 1000 µF capacitor (ELCO) 520-1090 € 1,31 min. voltage: 25V (depending on your motor voltage)
1 Red LED 708-2753 € 0,09
1 Green LED 708-2756 € 0,11
1 Yellow LED 708-2769 € 0,11
1 Laos PCB Rev 0.3 € 15,00 Available from our WebShop: http://wiki.laoslaser.org/index.php/WebShop

Connectors

Phoenix

Count Component RS Part No. RS Price Farnell Part No. Comment
7 Phoenix 4-pin terminal block 189-6032 € 3,05 3705377
7 Phoenix 4-pin PCB header 189-6127 € 1,04 3705195
3 Phoenix 2-pin terminal block 189-6010 € 1,746 3705353
3 Phoenix 2-pin PCB header 189-6105 € 0,51 3705171
1 pin-header 1x4 251-8632 € 1,056

JST (HPC LS3020 Pro)

The HPC LS3020 Pro uses low cost JST connectors on their cables.

Count Component RS Part No. RS Price Farnell Part No. Farnell Price Comment
1 WUERTH ELEKTRONIK 3WAY PCB connector RIGHT ANGLE 5.08mm 189-6571 € 0,62 1641987 € 0,60 PCB Power connector
5 JST 4 pin PCB connector B4B-XH-A (LF)(SN) 543-2733 € 0,16 1516278 € 0,20 Stepper drivers, Endstop & Laser and I2C
2 JST 4 pin housing XHP-4 353-1636 € 0,07 1516266 € 0,10 For endstop and laser cable (usually provided with laser)
1 JST 2 pin housing XHP-2 353-1614 € 0,05 1516264 € 0,05 To add laser power modulation
2 JST Socket insert BXH-001T-P0.6 353-1591 € 0,04 1516301 € 0,05 To add laser power modulation

Note - You need to modify the cables a bit to connect to the correct pins, see description in the HPC installation section. Connectors may have significant minimum order quantity. You may ask Peter if he has some he can supply when ordering the PCB.

JST (HPC LS3020)

The HPC LS3020 uses low cost JST connectors on their cables.

Count Component RS Part No. RS Price Farnell Part No. Farnell Price Comment
1 WUERTH ELEKTRONIK 3WAY PCB connector RIGHT ANGLE 5.08mm 189-6571 € 0,62 1641987 € 0,60 PCB Power connector
3 JST 4 pin PCB connector B4B-XH-A (LF)(SN) 543-2733 € 0,16 1516278 € 0,20 Stepper drivers, Endstop & Laser and I2C
2 JST Socket insert BXH-001T-P0.6 353-1591 € 0,04 1516301 € 0,05 To add laser power modulation
1 FFC / FPC connector 718-8772 (straight, untested) € 0,18 1816463 € 0,30 This connector combines X-axis and endstops!

Pololu Stepper Drivers

Number Component RS Part No. RS Price Farnell Part No. Farnell Price Comment
2-4 Pololu stepper drivers Depending on how many axes your machine has
4-8 8x1 pin-header socket 495-8587 € 1,25 3419101 € 0,56 You need 2 for each Pololu

The Pololu you need is of the type A4988: http://www.pololu.com/catalog/product/1182

We recommend a heatsink with the pololu, as sold here: ultimachine.com and here: reprap.me

Other parts

Number Component RS Part No. RS Price Farnell Part No. Farnell Price Comment
1 7805 398-697 € 0,23 Power regulation (see below)
1 2x4 DIL socket 402-759 Canbus IC holder
1 65HVD251 CAN chip 662-4321 Canbus IC
1 USB connector 719-9438 1642033 Usb Host connector
1-2 TIP 110 485-9648 9294201 Analog output

Power regulation

If your laser does not have a good 5V power supply built-in, you can add this 7805 power regulator. Note that it will get very hot if you feed it a high voltage. Anything between 7 and 12 volt should be ok. You can use a left-over power adapter to power the board.

The HPC series have a 5V power output built-in.

Older versions

The history of mainboards is available in Mainboard_Revisions

Attachments

Laos_rev3.png View - board, top view (30.8 KB) Anonymous, 2012-07-12 20:58

DSC_3506.jpg View (152 KB) Anonymous, 2012-07-12 21:27

laos-board-rev3.pdf - PDF of the schematics of rev0.3 board (126 KB) peter, 2012-09-09 15:41

PI_E453774.pdf - Rev 0.3 PCB rendering (516 KB) peter, 2012-09-09 15:45