Can I use Arduino pins in place of a switch for very low current at 5V?

I have a power outlet that is controlled by a little IC chip, which responds to a button-press. I found that by shorting the two button leads for 0.5 seconds, the chip will respond as though I had pressed the button, which is great. Now I want to control it with my Arduino. I measured the voltage across the button, which was a steady 5.05v. I put my multimeter in series with the button and got only 20-50uA while pressing it, so it's well within the Arduino's capability. I soldered a wire to each lead on the button so I can connect them to Arduino pins. However, I don't know how to mimic the function of a switch. I was thinking I could set one pin high and one low, then activate the button by setting them both low to mimic a short. Is my logic accurate? Or should I connect the positive lead to ground and the negative lead to a digital pin and activate by setting the pin high?

I figured it out!! The following code toggles the device between on and off every 5 seconds. When both pins are set LOW, a connection is made between them and it's like the button is being pushed.

int positive = 3;
int negative = 4;

void setup() {                
  pinMode(positive, OUTPUT);  
  digitalWrite(positive, HIGH); 
   pinMode(negative, OUTPUT);  
  digitalWrite(negative, LOW);  
}

void loop() {
  digitalWrite(positive, LOW); 
  delay(250); 
  digitalWrite(positive, HIGH);  
  delay(5000); 
}

Just make sure that the Arduino pin is not required to source or sink more than 20 mA.

...R

Roger that and thanks!

I think, that better would be to connect only the positive pin and the other side of switch (negative) connect to ground of arduino (if they are independently powered - if they are powered from one source of DC, then you should measure all voltages again common ground )