I apologize for my ignorance, but does a brand new IC need to be programmed or are they already factory programmed ready to be solder?

I have an M-Audio 49 MIDI controller piano with a bad 24LC16B-I/P IC and can't find a donor board to extract that IC, but they do have the chip on Ebay. I was wondering if brand new ICs have to be code programmed before soldering to the MIDI keyboard PCB, or they are factory programmed ready to solder?

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    \$\begingroup\$ 24LC16B is a programmable zero-power memory. The chip producer delivers them blank. It's up to the producer of the device it is used in to put the correct data into it. \$\endgroup\$ – Janka Nov 18 '20 at 0:47
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    \$\begingroup\$ R M - Hi, Just to avoid this being an XY-problem: Why do you believe that the 24LC16B is "bad"? \$\endgroup\$ – SamGibson Nov 18 '20 at 0:54
  • \$\begingroup\$ SamBigson....Based on my Flir thermal camera it pin point directly at the IC chip very hot at touch \$\endgroup\$ – R M Nov 18 '20 at 1:04
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    \$\begingroup\$ That thermal issue is unique and surprising. The chip will not come with any piano-related contents. The more interesting questions are if the failure is actually of the chip itself and alone or if it is collateral damage from something else, and if the product requires the chip to have particular contents or if it is only a place to store user options in a way that the firmware can (and is willing) to initialize from nothing. These are product specific questions unanswerable here, but only by further research/experiment on your part. \$\endgroup\$ – Chris Stratton Nov 18 '20 at 1:06
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    \$\begingroup\$ @RM - I think there is a terminology problem. It is possible for capacitors to be shorted. But if the EEPROM was removed & the capacitors "are no longer shorted", then they were never shorted in the first place! I'm guessing that you are talking about some measurements which you made (using either resistance or diode DVM ranges) across nearby power rail decoupling capacitors. As I said, my interpretation of your comment is that the capacitors were never shorted, but the measurements you made changed after the EEPROM was removed. Overall it suggests the EEPROM has failed catastrophically. \$\endgroup\$ – SamGibson Nov 18 '20 at 1:34

The 24LC16B is a 16 kb (2 kB) EEPROM.

Unless it is explicitly described by the seller as containing the required code for your MIDI keyboard, then any of them which you buy will either be blank, or contain other code (not uncommon for EEPROMs bought from the grey market), or perhaps a test pattern; none of which will work in your device if your device requires it to have specific contents.

It's too small to hold program code for an MCU of reasonable complexity, but it could be factory-programmed by your keyboard's manufacturer with something special, meaning that one bought from elsewhere wouldn't work as a replacement. Or you might be lucky, and find that it does work. It all depends on your MIDI keyboard design, and how it uses that EEPROM.

As you commented:

Based on my Flir thermal camera it pin point directly at the IC chip very hot at touch

That is clearly abnormal, and might indeed mean that the EEPROM is non-functional. However as commented by Chris Stratton, there is the possibility that the cause of that damage to the EEPROM is a fault elsewhere in the keyboard.


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