I broke the hantek DSO2C15 - Page 1
Forum section: electronics / testgear

author: eospss
author_rank: Contributor
timestamp: November 26, 2023, 04:22:15 am
content: I always felt like this scope was unstable and when I took the machine apart I found that the Lemontree 2090 had a rough welding. Some of the pins felt like they were only halfway touching the pads, so I decided to remove the chip and resolder it. Unfortunately, I did not master the stability and directness when removing the chip, which caused the Lemontree 2090 to be damaged. After booting, the machine freezes after initialization. There is no Lemontree 2090 for sale right now and I am looking for a replacement chip. Is anyone willing to provide relevant information? Thanks

author: Algoma
author_rank: Frequent Contributor
timestamp: November 26, 2023, 07:08:19 am
content: Review the post by David Alpha for more info about the chip.https://www.eevblog.com/forum/testgear/hacking-the-dso2x1x/msg3603156/#msg3603156I'm not certain there is a direct replacement available, some have requested a replacement mainboard from Hantek Support. Some of these large chips are already over half the cost of the scope to buy them from an available suppliers.

author: pcprogrammer
author_rank: Super Contributor
timestamp: November 26, 2023, 08:22:21 am
content: The ID within the bit stream shows it being a Gowin FPGA, but not precisely which one. It has to do with the memory within the chip. But it might be easy and cheap to find a replacement within China. I did findthis websitewhere they seem to be about 10 bucks US.I believe it to be the one with the 64Mb of SDR memory.Take a look at theschematicsI made. Or read more about thejourneyof making them.

author: DavidAlfa
author_rank: Super Contributor
timestamp: November 26, 2023, 10:11:11 am
content: As per the datasheet and the JTAG ID, likely a GW2AR-18-144.https://www.eevblog.com/forum/testgear/hacking-the-dso2x1x/msg3598420/#msg3598420Check thisdatasheet, alsothis one.However, there are several types, at least:GW2AR-LV18LQ144C7/I6GW2AR-LV18LQ144C8/I7GW2AR-LV18EQ144C7/I6GW2AR-LV18EQ144C8/I7GW2AR-LV18EQ144PC7/I6GW2AR-LV18EQ144PC8/I7Which one is actually used here, I don't now.LQ / EQ refers to the package :QuoteThe "P" (144P) refers to the memory type:Maybe this "Lemontree" is a custom device, having 128MBit DDR RAM in a 144-pin package?Rest is speed grade and temperature range:This guy replaced it, but either did a bad job or the replacement device was defective/incorrect:https://www.eevblog.com/forum/testgear/new-hantek-dso2x1x-models/msg4899533/#msg4899533https://www.eevblog.com/forum/testgear/new-hantek-dso2x1x-models/msg4798610/#msg4798610I'd take the fastest grade for sure. The package should be "EQ" (Bottom gnd pad).Only the memory type remains unknown.

author: ebastler
author_rank: Super Contributor
timestamp: November 26, 2023, 10:38:20 am
content: Quote from: eospss on November 26, 2023, 04:22:15 amLet's assume that the factory soldering was indeed not done right. Even in that case, unsoldering the chip was not necessary at all. You should just have added some flux and carefully re-soldered the connections.Since you are apparently not too experienced with soldering these fine-pitch chips:How sure are you that your new solder joints are all good, and that there are no solder bridges?If you have not done so yet, please inspect all joints closely under a microscope. If you find suspicious joints, add flux and re-solder them.Maybe the Lemontree chip is not damaged after all, and you can still fix your scope by cleaning up the soldering. Fingers crossed!

author: eospss
author_rank: Contributor
timestamp: November 26, 2023, 03:38:34 pm
content: Thank you all for your enthusiastic replies. Will high temperature cause the firmware to be lost? I definitely got carried away while soldering the chip. I shouldn't have done it when I wasn't sure how to deal with it, and I regret it very much now. GW2AR-18-144 This chip is not cheap either. I am not sure that it can be restored by replacing it after purchase, and whether this chip can work properly after being soldered. I don't even know if the firmware can be flashed in smoothly and work normally after replacing the chip.

author: eospss
author_rank: Contributor
timestamp: November 26, 2023, 03:48:41 pm
content: I checked with a high-power magnifying glass used to repair clocks, and I confirmed that there were no solder bridges forming directly on the pins.

author: pcprogrammer
author_rank: Super Contributor
timestamp: November 26, 2023, 04:16:53 pm
content: Quote from: eospss on November 26, 2023, 03:38:34 pmThe what you call firmware for the Lemontree chip is in fact a configuration bit stream and it is loaded into the chip by the CPU after power up. So replacing the chip with a new one does not need any additional action. Just properly solder it in and power up. With the correct chip it should work.

author: eospss
author_rank: Contributor
timestamp: November 27, 2023, 02:50:21 am
content: Quote from: pcprogrammer on November 26, 2023, 04:16:53 pmThank you for your reply. Can you confirm the specific fpga model? I'll see if I can buy it. And what is the chip next to Lemontree used for? Its model number was obliterated.

author: pcprogrammer
author_rank: Super Contributor
timestamp: November 27, 2023, 06:16:13 am
content: I'm not sure which one it actually is. It depends on the type of memory in it and if there is a ground pad underneath the chip. (P or no P), (LQ or EQ)The other chip is the ADC for converting the analog signal into the digital values. The consensus is that it is an ADC08D500.

author: eospss
author_rank: Contributor
timestamp: November 27, 2023, 09:55:40 am
content: Quote from: pcprogrammer on November 27, 2023, 06:16:13 amDuring the soldering process, I felt that the lower part of the chip should be grounded, because I used an air gun to heat the pins and gently lifted one corner with tweezers, only a little at a time. The temperature of the air gun reached 400°C and the chip still could not be removed. So I feel like there should be a ground pad underneath the chip.

author: pcprogrammer
author_rank: Super Contributor
timestamp: November 28, 2023, 07:30:10 am
content: In the case of a ground pad the EQ type should be used. Still leaves the question of the memory type.

author: eospss
author_rank: Contributor
timestamp: November 28, 2023, 02:15:44 pm
content: Quote from: pcprogrammer on November 28, 2023, 07:30:10 amSomeone mentioned that there were functional issues after replacing the GW2AR-LV18EQ144PC8, which uses PSRAM. So I think it should be GW2AR-LV18EQ144C8/I7, and I happened to see it on sale online. I plan to practice soldering first and completely remove the previous chip. Then buy a GW2AR-LV18EQ144C8/I7 and try it. If this doesn't work, we can only think that Lemontree is a custom chip. This process may take some time, after all, GW2AR-LV18EQ144C8/I7 is not cheap. Not sure what the impact would be if I didn't solder the ground pad. I also need to buy solder paste if I have to solder the ground pad. I actually don't want to invest more in a scope that has little hope of repair.

author: DavidAlfa
author_rank: Super Contributor
timestamp: November 28, 2023, 02:41:23 pm
content: Sorry to say it like this, but it seems you simply skipped any reading here or in 4pda.ru and went on your own taking the worst route without proper skills/equipment.If you failed at soldering some pins, replacing the entire IC doesn't look good!Probably there was nothing wrong with it in first place, maybe just lacking updates, or old FW version.Sometimes it will randomly hang, specially on long runs, it's simply impossible to run it for two hours straight without crashing.* It's just Hantek *.

author: eospss
author_rank: Contributor
timestamp: November 28, 2023, 03:56:28 pm
content: Quote from: DavidAlfa on November 28, 2023, 02:41:23 pmI already had some premonitions while trying to remove the chip. The chip removal was not smooth. The air gun temperature remains at 400°C for too long. In the end, it was still not completely disassembled. Then I realized there might be a ground pad underneath the chip. I put the chip back together and checked the pins to make sure there were no false solders or solder bridge on the pins.Before removing the chip, I pressed the corners of the PBC with my hands to cause some deformation. I found that the waveform was normal and the displayed values were also normal. This gave me the idea of soldering fpga.

author: ebastler
author_rank: Super Contributor
timestamp: November 28, 2023, 04:14:43 pm
content: I am afraid the thread title sums up the situation nicely: You broke that scope. To be honest, I don't think it is likely that you will be able to fix it again.Even if, with a bit of luck, we identify the right part and you can obtain that: How do you expect to solder it? You have not yet managed tounsolderthe presumably damaged part, due to its ground pad. The new part will have that ground pad too, and it will need to be soldered for good heat transfer to the PCB. There is also a good chance that you will start to lift traces and pads on the PCB, due to the heat treatment you gave it.I would start saving for a new scope, and looking around for opportunities to buy a used one if you are on a budget.

author: eospss
author_rank: Contributor
timestamp: December 19, 2023, 08:56:15 am
content: The machine works again. I purchased board washing water and cleaned the circuit board and re-soldered it. After the completion, the machine can boot normally and I updated the 3205 firmware. It's working fine now. It seems that the fpga was not soldered firmly before. Thank you all for your help.