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peteruithoven, 2013-03-05 23:07


PWM stands for Pulse Width Modulation and is used to control the power of the laser. On the HPC3020 you will see a mA meter and a turn knob that will allow you to control the power of the laser by hand. With PWM the Laos board can take over this function, which allows for e.g. engraving of pictures or controlling the right power settings for certain materials.

Example of enabled laser PWM

To use the power control from the LAOS board, you need to connect the laser PWM output (are we sure this shouldn't be connected to exhaust enable?) to the ANALOG input of your power supply. On the LAOS board this is J39, together with laser on. You need to make a two wire cable with a 3 pin JST on one side, and a 4 pin JST on the other side.

  • Use a 470 ohm (how much watt?) pull-up resistor between +5V and analog in at the laser power supply side.
  • "C" connects to the analog in pin (and resistor)
  • "E" connects to GND

(This image is slightly confusing because the 4 pin JST already contains 2 cables for the laser on connection, right?)

HPC3020 laser

hpc side, very much a poc (a what?) (How do I recognize the analog input? The image doesn't really help)
pwm hpc side
An alternative image of a power supply, could someone highlight the analog input?

laos side
pwm laos side

KIII laser

pwm-connector.jpg View (41.4 KB) hugomeiland, 2013-02-22 19:17

IMG_1154.JPG View - pwm hpc side (102 KB) hugomeiland, 2013-02-22 19:22

IMG_1157.JPG View - pwm laos side (102 KB) hugomeiland, 2013-02-22 19:22

power supply.JPG View (152 KB) peteruithoven, 2013-03-04 09:58

powersupply.jpg View (152 KB) peteruithoven, 2013-03-04 09:59

powersupply.jpg View (159 KB) peteruithoven, 2013-03-06 01:47

PWM.png View - PWM overview HPC3020 (44.1 KB) hugomeiland, 2013-03-11 12:04