Hello,
I am new to this forum, I have an SSD SU760 that stopped working, DC-DC converters components are heating up & also SSD controller is heating up. I need to identify some components on the board, they are all related to DC-DC converters. I have attached the files with the IC / components circled in red line.

In fig1

1. An SMD component of two SMT solder points with gold marking Data sheet URL / Drawing with pin name + definition.

2. An IC U3 with leads on 4 sides, 16 pins total, with marking Data sheet URL / Drawing with pin name + definition.
3123B
921J2

3. An IC U5, U1, U2 with 5 leads with marking Data sheet URL / Drawing with pin name + definition.
3102
925J2

4. SSD controller Realtek, RTS5733 DMQ Data sheet URL / power pin location.

5. An SOIC U14 of 8 leads with marking Data sheet URL / Drawing with pin name + definition.
2H919
DG408J

The general rule is to measure the voltages at the inductors. That's where you will find the outputs of the DC-DC converters.

MT3102, M3Tek, 1.5A Continuous 2A Peak 5V Input 2.5MHz Synchronous Step-Down Converter, marking 3102, DFN_6L:
https://web.archive.org/web/20161029112954/http://m3tekic.com/upload/2016/08/20160826154353.pdf

MT3123 / MT3123A / MT3123B, M3Tek, 5V 4A 1.25MHz 15æA Low Iq FAST-PWM Synchronous Step-Down Converter, marking 3123 / 3123A / 3123B, QFN3x3_16L:
https://web.archive.org/web/20190809212449/http://www.lctek.net/uploadfile/cfile/upload/2016852311282.pdf

W25X20CLUXIG, Winbond, 2.5/3/3.3V 2M-BIT SERIAL FLASH MEMORY WITH 4KB SECTORS AND DUAL I/O SPI, marking 2Hxxx & 0Gxxxx, USON 2x3-8:
https://www.mouser.com/datasheet/2/949/w25x20cl_revf_20150806-1489633.pdf

The "SMD component of two SMT solder points with gold marking" appears to be a fuse or polyfuse or polyswitch.

My datasheet database:

https://web.archive.org/web/20230522152029/http://www.users.on.net/~fzabkar/Datasheets/DATAURLS.HTM
https://web.archive.org/web/20230522152022/users.on.net/~fzabkar/Datasheets/datasheets.txt

_________________
A backup a day keeps DR away.

Hello,
Thanks for the quick reply,

This component "SMD component of two SMT solder points with gold marking" is heating up, also the voltage drop on this part is ~0.5V to 0.6V, this drop is a lot is it not?

For testing, I can jumper this component is it not? since you said, this is a fuse. Is it possible to know the mfg + part # of this comp?

This drive slowly deteriorated from functioning intermittently to fully dead; because of the heat!
I thought DC-DC components are robust; they don’t go bust like this?


Regards.

Hello,
Why there are two different step down DC-DC converters? I don't see any fast changing / unstable input?

MT3102 5 leads U5, U1, U2.


MT3123 16 leads U3

Regards

What are the output voltages of each converter?

_________________
A backup a day keeps DR away.

MT3102
U5 Output @ pin 3 / @L6: 1.83V / 1.79V
U1 Output @ pin 3 / @L1: 1.11V / 1.21V
U2 Output @ pin 3 / @L3: 3.33V / 3.52V

MT3123
U3 Output @ pin 16 / @L4: 3.33V / 3.33V

There is a drop of 0.5V to 0.6V between two leads of Fuse?

Those voltages look OK. The only concern I would have regarding the voltage drop across the polyfuse is if the voltage is low enough to trigger a power-on reset. You could bypass the polyfuse with a wire link or glass fuse for testing purposes.

The MT3123 converter might be providing Vcc for the NANDs. That could explain why it is heftier.

_________________
A backup a day keeps DR away.