2
\$\begingroup\$

enter image description hereenter image description hereenter image description here

enter image description here

Please help me identify the IC with top marking “GR”.

This is a PCB from a 12 V Lavazza 500 espresso experience coffee machine.

enter image description here

\$\endgroup\$
16
  • 5
    \$\begingroup\$ From watching a video of the coffee maker -- it has timing, flashing LEDs, beeping -- this is almost certainly a microcontroller. It may well be ready-programmed, and the marking is a manufacturer's internal code. It might be a standard processor, but it will be difficult to work out. You could start by tracing out the circuit and trying to identify IO pins. Are you asking for curiosity, or trying to repair one, or some other reason? \$\endgroup\$
    – jonathanjo
    Aug 2, 2023 at 9:33
  • \$\begingroup\$ I have about 10 pcs. for repair, this board in the picture is working. Will it be possible to read and write the microcontroller? Any idea what to use. Thanks \$\endgroup\$ Aug 2, 2023 at 10:05
  • 2
    \$\begingroup\$ I don't expect an MCU failure here. Did you check the relays? You could swap the ICs of a bad and a working PCB to verify the theory. \$\endgroup\$
    – Jens
    Aug 2, 2023 at 20:29
  • 3
    \$\begingroup\$ Tthank you all for the advice you gave. it's definitely the chip because when I exchange it with a working one and everything starts normally. I don't have any experience with microcontrollers. \$\endgroup\$ Aug 3, 2023 at 8:12
  • 1
    \$\begingroup\$ @TomaNikolov It's not a buffer chip, it's definitely a MCU. Gil is confused because you chose a random part as placeholder in your schematic. \$\endgroup\$
    – nanash1
    Aug 5, 2023 at 10:08

1 Answer 1

3
\$\begingroup\$

This is not really answer, but an extended comment. I doubt the question as it stands has a realistic chance of being answered. From your comments, I understand, your plan is to find out what IC the one in the SOP16 package is and then buy a replacement to fix this coffee maker. I don't think this will work and here is why:

First, as others have commented, it's a MCU. SOP16 is a pretty big package by modern standards. It offers a lot of real estate for markings and most manufacturers (even cheap Chinese ones) will use it to write the full product code, a logo and lot numbers/date codes. The fact that this one is marked only with two letters tells us that this is probably not an off the self product, but likely in some way customized. This means that finding out what it is from the information given is exceedingly unlikely.

I traced out the circuit (purely visual trace, no grantee), so you can check what the connections are, but I couldn't find anything compatible when searching for the markings.

enter image description here

But even if you manage to find out what exactly this MCU is, you're not really any further in repairing it, because you would need to dump the firmware from a working unit and flash it to your replacement. This is not really practical. The only realistic way to replace this MCU (apart from donor boards of course) is a making a functional replacement. This means you have to reverse engineer the functions of this MCU and then write your own firmware for a 5V MCU of your choosing. This is not easy for a beginner and will take a lot of work, but the functions here are probably not too complicated. When the user presses start, it runs the pump and the heater until a certain temperature is reached. Then it beeps to let the user know the espresso is ready.

\$\endgroup\$
20
  • \$\begingroup\$ Very nice work on the diagram. \$\endgroup\$
    – jonathanjo
    Aug 6, 2023 at 8:59
  • \$\begingroup\$ @nanash1 first of all kudos for a job well done.thanks a lot!! I will be very happy if you contact me [email protected] \$\endgroup\$ Aug 6, 2023 at 9:17
  • 1
    \$\begingroup\$ I completely agree with nanash1's comments about how it's not easy for a beginner. It might just be possible to make a pin-compatible functional replacement with pretty much any microcontroller on some kind of carrier board. But I notice that Microchip's 14-pin microcontrollers eg 16F256 might just possibly be able to fit right onto the footprint, with MCU pin 1 on pin 2 of the PCB. You'd have to get power to PCB pin 15, which appears unused. This definitely would be uneconomic in development time, but if you wanted an educational project some people would consider it fun. \$\endgroup\$
    – jonathanjo
    Aug 7, 2023 at 10:48
  • 1
    \$\begingroup\$ @TomaNikolov You should stick to well known brands with good support like Microchip, ST or NXP. The obvious choice for something like this would be a PIC or AVR 8 bit MCU. \$\endgroup\$
    – nanash1
    Aug 7, 2023 at 12:12
  • 1
    \$\begingroup\$ @TomaNikolov this is not the place to solicit proposals on this sort of thing, and regardless, I don't expect you would be able to get this done for <$10k. \$\endgroup\$
    – flaviut
    Aug 7, 2023 at 16:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.