SOT23-6 with marking code 05 or O5 - Page 1
Forum section: electronics / repair

author: icezebra
author_rank: Contributor
timestamp: February 07, 2023, 08:37:32 pm
content: I have tried a lot of things, such as the ideas discussed in:https://www.eevblog.com/forum/chat/(tips)-how-to-identify-smd-devices-from-the-marking-codes/msg4683560However I cannot identify this TSOT23 six pin device (SOT23-6) with marking code05orO5It might be a TVS, or a Linear Regulator, or a FET.It is NOT TVS SMS05Also, what is the long black thing markedEAUEin the second photo?Help!

author: mariush
author_rank: Super Contributor
timestamp: February 07, 2023, 09:50:21 pm
content: It looks like the bottom 3 pins are connected together, so that makes me think it may be a n-channel mosfet on npn transistor.As for that rectangular black part, it makes me think it's be a shock sensor or orientation sensor, maybe to detect drive falling or something like that.... but it's much more likely it's just an oscillator / crystal, based on the two ceramic capacitors that seem to be connected to the pads at the endThe chip under it is probably a 2 gbit slc nand chip from Micron.

author: fzabkar
author_rank: Super Contributor
timestamp: February 07, 2023, 10:14:16 pm
content: The Micron chip is MT29F2G01ABAGDWB-IT:G.https://www.micron.com/support/tools-and-utilities/fbga?fbga=nw874https://nand.gq/#/decode?pn=NW874

author: icezebra
author_rank: Contributor
timestamp: February 08, 2023, 12:50:13 am
content: Much obliged for the responses so far.I should mention that the chip next to the "05" SOT23-6 devices is an SMPS synchronous buck controller MP1657 with two internal MOSFETs. One internal MOSFET is doing the function of the free wheeling diode in a normal buck converter and the other is the "switch" in a normal buck converter. I have no idea what the external SOT23-6 "05" devices are, but I do not think they can be operated by the MP1657 (for which I append the datasheet.)On other places on this PCBA there are linear regulators near the SMPS presumably to further regulate the output of the SMPS. There are a total of 6 SMPS and 2 Linear regulators on this PCBA not including the two05devices. Cray-cray. See new photos attached for more detail.https://en.wikipedia.org/wiki/Buck_converterAlso, your are correct, thatISa FLASH device. This PCBA is the main Linux Processor PCBA of a Reolink RLC-510WA IP Camera. I think it has both NAND and NOR Flash onboard.So the black thing is likely a crystal then. Good observation with the caps and the proximate FLASH device. I don't think it is an orientation sensor but I suppose it could be a reed switch or a shock sensor. I will stick a scope on it if I get the PCBA working again, and update this thread with the result. The MP1657 has failed and I ordered a new one today. I was trying to determine what the05devices were in case I also need to replace them. Since they could be FETs I was reluctant to probe them without knowing the pinout.More info here:https://ipcamtalk.com/threads/reolink-hardware.68214/

author: icezebra
author_rank: Contributor
timestamp: February 08, 2023, 12:53:28 am
content: MP1657 Datasheet

author: fzabkar
author_rank: Super Contributor
timestamp: February 08, 2023, 01:35:30 am
content: Could those be protection devices for the SD card, perhaps an ESD diode array (3 signal lines per chip)?There is a row of 7 pads behind the card socket on the other side. I suspect there will be continuity between each signal pad and one of the "05" pins.

author: icezebra
author_rank: Contributor
timestamp: February 08, 2023, 05:25:18 am
content: @mariush, thanks to your insight with the capacitors I have identified the back EAUE thing as a "Low Load Patch Crystal" part number MC-146https://www.aliexpress.com/item/1005002886890490.htmlhttps://www5.epsondevice.com/en/products/crystal_unit/mc146.html@fzabkar that is some brilliant detective work. I suspect your are very likely correct. I will measure the devices with a diode checker. I will not have access to them again until March. In the interim, I will search the diodes on Ali-Express!Thank-you to both of you for taking a genuine interest in this, I greatly appreciate your kind assistance.

author: icezebra
author_rank: Contributor
timestamp: February 08, 2023, 05:42:28 am
content: I want to say SRV05.On-Semi and LittleFuse and Semtech all make it with different markings. The Semtech marking isV05https://www.aliexpress.com/item/1005004126847506.htmlhttps://semtech.my.salesforce.com/sfc/p/#E0000000JelG/a/44000000MCn6/BeAzV1kgq8LEQB.FR71VkMB1v3NUxVrSyFjXw9p4pnk

author: fzabkar
author_rank: Super Contributor
timestamp: February 08, 2023, 06:16:29 am
content: Quote from: icezebra on February 08, 2023, 05:25:18 amCongratulations. I was thinking that it may be a "tuning fork crystal" or "watch crystal".

author: gamalot
author_rank: Super Contributor
timestamp: February 08, 2023, 05:59:57 pm
content: I can't find a component in a SOT23-6 package marked 05, maybe a compatible part for SMS05.https://semtech.my.salesforce.com/sfc/p/#E0000000JelG/a/2R0000001OfW/uM7qnDGNH0YlhXQ3LfpChJNLPGRP1iIkH1Mh_q3hrxM

author: icezebra
author_rank: Contributor
timestamp: February 09, 2023, 10:22:58 am
content: Quote from: gamalot on February 08, 2023, 05:59:57 pmIndeed professor @gamalot indeed!An equally probable candidate to the one last proposed (SRV05). The reason I ruled SMS05 out in the first post was because the marking is05/05.https://www.aliexpress.com/item/4001089229496.htmlIn hindsight, perhaps that was a bit hasty, as the SRV05 fits no better, with a marking ofV05.https://www.aliexpress.com/item/1005004126847506.htmlThey both have a similar pinout, with one measurable difference. On SMS05, there is a short between pins 2 and 5. Therefore, as soon as I can get an ohm meter on it (March 2023) I shall report the outcomes, including possible connection to the SD card as postulated by Dr. @fzabkarI am greatly encouraged by all the engagement and support in this thread. It is a rather pedestrian challenge, yet you have all deployed the full force of your deductive reasoning and SMD marking research skills. As as a result we have had some breakthroughs and some great leads to be followed up, not to mention the learning and skill/knowledge transfer that has occurred as a result, which benefits all members of this forum as well as future Googlers.Sir Isaac Newton summed up this sort of community support and intellectual tag-teaming rather nicely:https://en.wikipedia.org/wiki/Standing_on_the_shoulders_of_giants