esmi83:
LeoPhi - Sparky's Widgets
is the microcontrollers the same?
It probably is a microcontroller, but it is very unlikely it's an atmega32u4 as used in the link mentioned. The arduino-PH-meter-controller uses the same exterior as the chip in your meter, but internally it may differ a lot.
Looking only at their microcontrollers, and only those using this so called tqfp-44 exterior, Atmel (producer of "arduino" chips) sells about 85 different ones and for sure isn't the only one company on the market.
Quite often texts on chips are small /poorly readable, but with a good light and magnifying-glass it's often possible to find out what chip it is. Knowing which one it is may help you/us one step further.
The same is true for the LCD. Could you give us any info you can find on both ?
It's a pity the back is covered with glue. It wouldn't surprise me the rectangular block houses an opamp.