Problem with cycling Allegro 3144 Hall sensor

Using Arduino Sensors
1

Hi All,

I'm trying to test some allegro hall effect switches that i recently bought from ebay ( model 3144)
I put up a really simple circuit and wired my sensor correctly.5V to 5V , GND to GND , output to digital input arduino.
My basic code just read a digital pin ( where the sensor is tied) and prints out the state of the switch.

but what i found was not what i expected to read.

If i place a magnet (even really strong ) near the sensor, the state stills LOW.
If i place an AC line ( the one that powers my laptop) near the sensor, it start cycling between a series of zeros and ones. Like this: 0000000000001111111111111110000000000000000111111111111100000000
I noticed that the "period" of this sequence is determined by the distance between the sensor and the AC line: AC line next to -> long streaks of 0 and 1
AC line quite far to --> short streaks.

I also tried to add a 10k pullup resistor between 5v and output pin as i saw in some tutorials, but if i stick it, the signal goes HIGH and no changes are visible even with magnets/ac lines.

i expected the switch to close in presence of EMF and to open in absence of these. Where i'm faulting?

2

344 or 3144 ??
The latter want higher voltage for Vcc (try with external power)

3

Sorry, i realized now ( following your comment) that the ebay insertion reported 344 and my IC reported 3144. I now corrected the Subject. But 3144 datasheet reports minimum input voltage 4.5V .

4

Update:

I tried to tie the output to an analog pin.
what i found is similar to past results but i got some new information.
In analog values , the streaks of zeros and ones is represented by a series of values that reminds me of a sinus waveform:

So:
0000000000000000001111111111111111111111100000000000000000000000
Becomes like:
0 12 24 49 69 89 122 244 | 370 423 578 790 901 1011 906 756 547 433 376 | 234 111 90 65 32 21 11

and i also noticed that the higher value of the '1' streak ( 1011 in this example) is proportional to the distance between the sensor and the line. If i put the line a little more far from the 3144 , values are down scaled to a lower highest value ( i.e 700 )