LDR sensor (digital) sensitivity


i have this module

i use the digital pin as interrupts to wake up my arduino. that work fine but when i move my project to less light room it does not trigger well.(direct light <> darkness = oke, less light <> darkness = no trigger).

How can i make it more sensitief? i have try different potentiometer (10k,50k), LDR (GL5506,GL5537)
Or is there a beter LDR module then this one?

I give up and i need your help

(i think this is my module. i am not sure)

The module uses an LDR with pullup (or pulldown) resistor.
Connected to the analogue out.

And a threshold detector (the LM393).
Connected to the digital out.

Light/dark threshold (not sensitivity) can be set with the pot.
The LM393 has some hysteresis that might be too much for your application.

The two resistors between the LDR and the chip are most likely the pullup resistor and the hysteresis resistor.

I don't think that schematic is for that board.


To get more range out of an LDR, I use two or three resistors to power the LDR. The resistors are connected to outputs of the Arduino. One output can have a 1k resistor and one output can have 100k resistor (or even more).
I power the outputs one by one, and average the result. With that, I can see the difference between a dark night and a night when the moon is shining.
I don't use such modules, and because of the high value of the 100k resistor, it needs to be close to the Arduino and I use delays before taking a sample with analogRead() and I do averaging of a number of samples.

This schematic might be the one:

"One output can have a 1k resistor and one output can have 100k resistor (or even more)"

??? is that the R1

So there is nothing that i can do to fix(more sensitive) my LDR module.

And is there any LDR module on the market that i can use? (more sensitive than this one).

The LDR itself is sensitive enough!. Skip the board - desolder the LDR. Connect it is series with resistor(s).
Read Koepels answer again…

I agree with knut_ny. Use a LDR and a resistor. If you ask me, desolder or cut the LDR from the board and toss the board away. Try a few different resistors and see what happens.

Did you know that a LDR costs 3 cents ? (when you buy 100 of them at aliexpress).

i wish i can do that but i need the digital trigger to wake my arduino (attachInterrupt()). that is why i purchased this module. digital trigger with threshold)

( i have read in forum someone have try LDR analog on an Interrupts Pin. its dont work because voltage range 1.0-5v)

Then find resistor R1 of 10k, and replace the 10k with a higher value.