Successful repair of Siglent SHS1102 oscilloscope not turning on - Page 1
Forum section: electronics / repair

author: tarantula
author_rank: Contributor
timestamp: April 25, 2019, 03:57:28 pm
content: Hi,I have a Siglent SHS1102, a portable oscilloscope that has two galvanically isolated inputs. Despite a few quirks with saving data, it's a remarkably nice instrument. It's only a few years now and suddenly it didn't turn on anymore. I checked the battery and that was at 0 V, meaning the protection probably switched it off. I bought a new battery from Siglent (worked very well, I was surprised, 2018 timestamp even) and the oscilloscope came back to life. For half a hour.I had already checked whether there was any input to the battery before, but there wasn't. Since buying a new battery was a reasonable choice over taking the thing apart and potentially ruining it, I didn't follow up on this issue and hoped that it was just detecting whether a battery is present or not before charging. Since the second battery just ran dry and the instrument also didn't turn on without a battery I finally took it apart.There are a bunch of switchmode regulators on the lower quarter of the main board. None of those was a dedicated LiPo-charger, though. I searched, until I finally found the LiPo-charger: U27, a Texas Instruments BQ24170:http://www.ti.com/product/BQ24170Checking the voltages, I found an almost absent output voltage (300 mV or so) but also no input voltage to the IC! Aha!I looked at the datasheet and traced the elements from the recommended schematic on the board. There are two transistors regulating the input voltage: Q1 and Q2. As it happened, these are right next to the input plug: U24 and U25. While measuring them, U25 had a nice diode drop across source and drain, but U24 was short circuited across S and D. I guess that is dead!The markings on these things were a bit enigmatic but turned out to correspond to the suggested device from the datasheet:TI CSD17313http://www.ti.com/product/CSD17313Q2So I invested the 50 Cents at Mouser and got me a nice new one. Reworking the board wasn't too difficult despite the large ground planes and double sided (components on both sides!) board. 400 °C hot air and covering all the parts around with Kapton tape. I put the oscilloscope back together e voilâ, it came back to life and is now also nicely charging the LiPo.I suspect that the Fet might have overheated, as one of the thermal pads (source) might not have been soldered well. It didn't have any solder on it on the broken IC, so maybe there was a wicking issue.Attached are pictures of the device and the repaired FET (pink arrow). Maybe it helps somebody some day!

author: tarantula
author_rank: Contributor
timestamp: April 25, 2019, 03:58:07 pm
content: more pics

author: tarantula
author_rank: Contributor
timestamp: April 25, 2019, 03:58:38 pm
content: and a last one

author: kosomsk
author_rank: Regular Contributor
timestamp: April 25, 2019, 04:06:13 pm
content: Hi, Bro! Can you dump firmware from ic on bottom side? My SHS806 is firmware brickedMay be yor dump of U6 can help me to repair my oscilloscopehttps://www.eevblog.com/forum/repair/try-to-find-siglent-shs806-oscilloscope-firmware-(dump)/

author: tarantula
author_rank: Contributor
timestamp: April 25, 2019, 04:16:20 pm
content: Hi,which one is U6? I don't think I have any hardware to dump the IC. How would I do that? Also, some of the screws holding in the board are just threaded into the plastic and one is already stripped. I glued it back for now but it doesn't seem the device is made for repeated disassembly.If you have instructions for dumping it without bricking my device, I can of course give it a try.

author: kosomsk
author_rank: Regular Contributor
timestamp: April 25, 2019, 04:25:55 pm
content: U6 is located on the back of the board. To read the chip you need a JTAG or NOR programmer. You can not help me (

author: tarantula
author_rank: Contributor
timestamp: April 25, 2019, 10:01:02 pm
content: I guess not. Sorry. Good luck anyway!

author: Alex2trois
author_rank: Contributor
timestamp: September 24, 2024, 09:27:37 am
content: Hello everyoneI have a broken Siglent SHS1102 oscilloscope, the screen remains blocked at startup, even when pressing the scop button, no reactionJust once pressing the F1 key:ver_soft 3.01.02.02r7ver_hard: 8-21-3.3Of course impossible to boot from a USB keyDo you have a solution to offer me?I am not an electronics engineer but only an electricianIs it possible to download the SHS1000 firmware and then load it with a programmer?Can the RT809HSE programmer be used?Thank you, see you soon

author: tautech
author_rank: Super Contributor
timestamp: September 26, 2024, 06:48:23 am
content: See post:https://www.eevblog.com/forum/repair/siglent-oscilloscope-screen-shs1102-frozen/msg5655383/