52BAC - SMD Marking - Page 1
Forum section: electronics / repair

author: 2X
author_rank: Frequent Contributor
timestamp: December 10, 2023, 10:01:40 am
content: Hello, I have a DC to DC converter (LQS30A48-5V0RANY) and has a chip "52BAC - SMD Marking" and I can't find his part number/datasheet. I searched on the below sites with no result (I search also with 52BA). Any ideas?LQS30A48-5V0RANY:https://www.datasheets.com/id/part-details/lqs30a48-5v0rany-advanced-energy-industries--inc-413352163#datasheethttp://www.smdmark.com/en-US/search/code?id=52BAChttp://markingcodes.com/search/c/52BAC

author: 2X
author_rank: Frequent Contributor
timestamp: December 16, 2023, 09:57:38 am
content: I tryied to majke a schematic (the PCB is over 2 layers - so maybe there is something that I have miss) and I meaured with an oscilloscope at the pins on the unkmown chip on the PCB where it is working fine. I can't understand what chip is this... I don't beleive it is a dual transistor/mosfet.. maybe is is a buffer or a flip-flop?

author: Jwillis
author_rank: Super Contributor
timestamp: December 16, 2023, 10:59:54 am
content: I far as I got was TSOP-6.You did notice the 8 pin device beside it has a crack in it?

author: 2X
author_rank: Frequent Contributor
timestamp: December 16, 2023, 01:01:45 pm
content: Quote from: Jwillis on December 16, 2023, 10:59:54 amI have already replaced this chip (UCC2808AQDR-2Q1)... the problem is this with 6 pin where is shorted and I can't understand what chip is it.https://www.ti.com/lit/ds/symlink/ucc2808a-2q1.pdf?ts=1702731655924&ref_url=https%253A%252F%252Fwww.google.com%252Fhttps://gr.mouser.com/ProductDetail/Texas-Instruments/UCC2808AQDR-2Q1?qs=GmduDEHXyCqrQmPKOOZApw%3D%3D

author: fzabkar
author_rank: Super Contributor
timestamp: December 16, 2023, 02:56:36 pm
content: I think the IC could be a PWM controller,.in which case there should be an inductor in the circuit Perhaps you missed it because it would measure 0 ohms on the resistance range of your multimeter?Edit:I'm not sure about the PWM controller idea. Pictures 1 and 2 seem to be the inputs and outputs of a dual inverter, so I'm wondering whether the IC is a dual inverting MOSFET driver. This means that the control and voltage feedback must be coming from, and going to, the preceding stage, which appears to be the UCC2808A PWM. The output stage should still have an inductor, though.This is the kind of IC I'm thinking of, in terms of functionality (TC4426):https://ww1.microchip.com/downloads/en/DeviceDoc/20001422G.pdf

author: 2X
author_rank: Frequent Contributor
timestamp: December 16, 2023, 04:15:03 pm
content: Quote from: fzabkar on December 16, 2023, 02:56:36 pmThe idea that a converter have inductors is in my mind too. As I understand because these converters have isolation between input and output... the inductors I believe that implemented with circled lines below these ferrite orthogonals (on the red circles in the attached image). Also, can you understand what package is the chip that I am looking for? Is it "TSOP-6" like the "Jwillis" wrote above or a "SOT", "SD", "SC70" package? Thanks a lot for your reply.

author: fzabkar
author_rank: Super Contributor
timestamp: December 16, 2023, 04:50:08 pm
content: I believe that the high-side MOSFET should connect to the positive power rail rather than ground, and the other terminal should connect to 5Vout via an inductor. That's the only configuration that makes sense to me.I also believe that OUTA/OUTB of UCC2808A should connect to INA/INB of the mystery IC.What is the supply voltage for UCC2808A? Is it the same as the mystery IC? I expect it should be around 10V.BTW, I searched for dual gate drivers in 6-pin packages and found only a few. None had the desired pinout.