Synology DS1815+(SMD) damage what is the replacment part? HELP! - Page 1
Forum section: electronics / repair

author: Warren_K
author_rank: Newbie
timestamp: October 08, 2022, 09:37:40 pm
content: WOW!!!!I guess while I was doing a memory upgrade I some how managed to bump the component off. and now doesn't power up.It just clicks, Atom resistor fix done some years ago.I would like to replace it but have no idea what part it is.DS1815+ U37 ( I guess it's a power mosfet or voltage regulator?? But I have no idea the value etc etc)HELP HELP HELP!!!Any help Greatly appreciatedThanks Warren.

author: fzabkar
author_rank: Super Contributor
timestamp: October 08, 2022, 09:57:18 pm
content: NJM78L03A, 3-Terminal Positive Voltage Regulator, 3.0V, 300mW, marking 8B, SOT-89:http://datasheet.iiic.cc/datasheets-1/new_japan_radio/NJM78L03A-_T2_.pdfThis is an image of the 9V version:https://www.digchip.com/datasheets/photos/330/NJM78L09UA.jpgThe styling of the "8" differs, so I may have incorrectly identified the part.

author: Warren_K
author_rank: Newbie
timestamp: October 08, 2022, 10:47:49 pm
content: @fzabkar Thanks for the replyOK 8B = SOT-89, What does the GE refer to? Sorry for the the newbie questionsWarren

author: fzabkar
author_rank: Super Contributor
timestamp: October 08, 2022, 11:32:44 pm
content: The second pair reflect the year and month of manufacture.

author: Warren_K
author_rank: Newbie
timestamp: October 08, 2022, 11:36:09 pm
content: OK Gotcha

author: fzabkar
author_rank: Super Contributor
timestamp: October 08, 2022, 11:47:08 pm
content: Before you replace it, you need to satisfy yourself that it is indeed the correct part. A 3.0V regulator would be an unusual choice, so I would be careful. Try to determine which, if any, ICs are connected to the Vout pin.My other reservation is that one would normally expect to see a filter capacitor on each of the Vin and Vout pins.

author: fzabkar
author_rank: Super Contributor
timestamp: October 09, 2022, 02:54:11 am
content: Here is a 6V regulator (UPC78L06T) with the same "8B" marking:http://www.eric1688.com/product.aspx?id=384507http://datasheet.octopart.com/UPC78L06T-E1-AZ-Integrated-Device-Technology-datasheet-149188871.pdfhttp://eric1688.com/mobile/product.aspx?id=365157(KIA78L06F, marking 8B)https://datasheet.lcsc.com/lcsc/1810301518_KEC-Semicon-KIA78L12F-RTF-P_C112764.pdf(KIA78L06F, marking 8B)

author: Warren_K
author_rank: Newbie
timestamp: October 09, 2022, 07:48:38 am
content: I agree the (UPC78L06T) 8B marking looks very much like mine, The other one the 8 is in a different styling.

author: gamalot
author_rank: Super Contributor
timestamp: October 09, 2022, 02:26:29 pm
content: Quote from: Warren_K on October 09, 2022, 07:48:38 amThe UPC78L06T is a bit old for your Synology, I suggest you double check the working voltage of the circuit powered by this regulator, using the wrong chip may cause more damage.To me (I am not sure) it looks like NJM78L03UA.

author: wasedadoc
author_rank: Super Contributor
timestamp: October 09, 2022, 05:16:56 pm
content: Power it up as is and measure the voltage at the input in. If it is less than 6.5 Volts then it surely is not a 6 Volt regulator. If it is more then still uncertain.

author: fzabkar
author_rank: Super Contributor
timestamp: October 09, 2022, 05:35:25 pm
content: Quote from: gamalot on October 09, 2022, 02:26:29 pmThere is a 3.3V LDO regulator (1117-33) at U38. It doesn't seem logical that there would be a 3.0V regulator nearby. :-?

author: wraper
author_rank: Unknown
timestamp: October 09, 2022, 05:48:04 pm
content: Such complicated devices have many voltage rails, so 3V and 3.3V in the same board is nothing unusual. 6V on such board is nearly impossible, also 78L06 needs al least 8.5V input voltage to work reliably, not 6.5V as it's not an LDO. 78L03 also needs at least 2.5V more that output voltage, so its input should be at least 5V. You can easily verify if it's indeed a (fixed voltage) voltage regulator. One pin should be connected to GND and input pin should have a voltage rail on it.

author: Warren_K
author_rank: Newbie
timestamp: October 10, 2022, 04:06:52 am
content: Quote from: wasedadoc on October 09, 2022, 05:16:56 pmon the in (Pin3) I'm getting 5.35volts on my multi-meter

author: Warren_K
author_rank: Newbie
timestamp: October 10, 2022, 04:14:42 am
content: Quote from: wraper on October 09, 2022, 05:48:04 pmI totally agree soo many different IC's on the otherside of the board, close to the backside of this regulator is an ALTERA "something" II ("MAX' perhaps) FPGA (has an Synology sticker over the rest of it)

author: Warren_K
author_rank: Newbie
timestamp: October 10, 2022, 04:23:16 am
content: Quote from: fzabkar on October 09, 2022, 05:35:25 pmYes 5v in on the (1117-33) at U38 and 3.3v out

author: Warren_K
author_rank: Newbie
timestamp: October 10, 2022, 04:33:33 am
content: 2nd reading on the broken Regulator the input voltage is 5.1v and in its current state 0.50v the output

author: Warren_K
author_rank: Newbie
timestamp: October 10, 2022, 04:49:18 am
content: I did a continuity test on output pin, Goes back to a PIC micro controller on the other side of the board (PIC16LF1829) datasheet says 1.8v• Sleep mode: 20 nA @ 1.8V, typical• Watchdog Timer: 300 nA @ 1.8V, typical• Timer1 Oscillator: 650 nA @ 32 kHz, 1.8V, typical• Operating Current: 48 μA/MHz @ 1.8V, typicalThat sound right to you's?

author: kripton2035
author_rank: Super Contributor
timestamp: October 10, 2022, 06:21:16 am
content: noyou should read this part of the datasheet1.8V-3.6V Operation – PIC16LF1825/9so the pic works from 1.8v to max 3.6Vso the regulator must be 3.3v max output

author: wraper
author_rank: Unknown
timestamp: October 10, 2022, 11:50:06 am
content: Quote from: Warren_K on October 10, 2022, 04:33:33 amSo it should not be 78L03 as input voltage is a bit too low for guaranteed operation. You did not answer if one of the pins is connected to GND. On the PCB picture it does not look like its tab is connected to any copper pour on the top side. EDIT, there is no exact droput voltage figure in the datasheet of NJM78L03A but chart suggests it's 1.5V, so it could be used with 5V input with thin margin.

author: wraper
author_rank: Unknown
timestamp: October 10, 2022, 12:07:29 pm
content: Also it could be RH5RL28AA (2.8V). By 5.1V on pin 3 do you mean the same pin numbering as on this picture?

author: kripton2035
author_rank: Super Contributor
timestamp: October 10, 2022, 01:35:55 pm
content: ohhh and second thought ! the pic is a 16F1829 and not 16LF1829 !!!!see pictureso on the datasheet the max voltage becomesQuoteso the regulator can be a 5v one...

author: wraper
author_rank: Unknown
timestamp: October 10, 2022, 01:39:06 pm
content: If that part of circuit is powered from 5V, then it should be a MOSFET, not LDO.

author: fzabkar
author_rank: Super Contributor
timestamp: October 10, 2022, 05:02:57 pm
content: Quote from: wraper on October 10, 2022, 01:39:06 pmThe circuit reference is U37. The transistors are Qs.

author: AndyBeez
author_rank: Frequent Contributor
timestamp: October 10, 2022, 05:35:26 pm
content: And another one!This ST Microelectronics variant of the Sot-89 8B package has an output voltage of 18V. Yes, eighteenSee Table 30 Marking Information:https://www.st.com/resource/en/datasheet/l78l.pdfAt least a Sot-89 is not too difficult to solder

author: kripton2035
author_rank: Super Contributor
timestamp: October 10, 2022, 07:12:37 pm
content: you should measure the voltages at the three exposed pins of U37two should be zero, and one around 6v if it is a 5v regulator, 5v if it is a mosfet switch, and around 4v if it is a 3.3v or 3v regulatoras there already is a 3.3v regulator just beside U37 (the 1117-33 chip), it should be 5 or 6v

author: wraper
author_rank: Unknown
timestamp: October 10, 2022, 07:52:13 pm
content: IMHO with 95% probability it's an LDO with <3.3V output voltage. There is no place for 6V on a basically computer PCB like this. Not to say OP already said there was 5.1V on one of the pins.