Dimming A Meanwell CC Driver with an Arduino Uno

Other Hardware LEDs and Multiplexing
1

Can anyone help me understand how to connect my Arduino Uno rev3 to my Meanwell LDD-700HW in order to dim the constant current driver? MW LDD-700HW datasheet

  1. I have a 9V 1A DC wall wart running into my MW Vin.
  2. I have the Vout+ and Vout- running out to my led string
  3. I have the dim lead running to pin 3 running the following code:
int led = 3;

void setup() {                
  pinMode(led, OUTPUT);     
}

void loop() {
  analogWrite(led, 50);  
}

I have read 20+ threads where people ask the same question and apparently they are all sharper than me. I gather it has something to do with making a common ground between my arduino and the MW-700 but I have yet to work out what specifically to connect. I have tried connecting the ground of my Uno (each of the 3 not that one should work and the others not) to the Vout- terminal and I get no dimming effect at all. I found another thread that makes it sound like I need to connect Vin- to Vout- to my Uno's ground but that seems a little sketchy to me. Can anyone clear this up for me?

2

Connect the ground of the Arduino to the -Vin, and connect the negative of your power supply also to -Vin.