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Electronics => Repair => Topic started by: killingtime on March 22, 2023, 10:24:01 pm

Title: Component Identification - PJ1499 LZ
Post by: killingtime on March 22, 2023, 10:24:01 pm
Hi,

Anyone know what this component is:

https://i.ibb.co/DprLPHY/Untitled.jpg

Can't find any info on the marking. It came from a switch mode supply and was connected across the supply rails just before the mosfet switch (it's not the rectifier diode after the mosfet - that was much bigger).

It was letting the magic smoke out. Guessing it's either a diode or tantalum cap. Measures 3 ohms in both directions. The PSU works fine without it.

One other thing. All the schottky diodes in a bridge rectifier config had a forward Vf of 0.2v and a reverse Vf of 0.7v (in circuit). They were all fine. Shouldn't they be open circuit in reverse?

Thanks.
Title: Re: Component Identification - PJ1499 LZ
Post by: fzabkar on March 22, 2023, 10:59:53 pm
I suspect it's a unidirectional TVS diode.

http://www.smdmark.com/en-US/search/code?id=lz (http://www.smdmark.com/en-US/search/code?id=lz)
Title: Re: Component Identification - PJ1499 LZ
Post by: Kim Christensen on March 22, 2023, 11:28:30 pm
Quote from: killingtime on March 22, 2023, 10:24:01 pm
One other thing. All the schottky diodes in a bridge rectifier config had a forward Vf of 0.2v and a reverse Vf of 0.7v (in circuit). They were all fine. Shouldn't they be open circuit in reverse?

That's the problem with measuring things in circuit. Other components are in series/parallel with them. Take those readings with a grain of salt.

Title: Re: Component Identification - PJ1499 LZ
Post by: killingtime on March 25, 2023, 12:34:37 pm
Found a website that says it could be a schottky diode. Equiv: PJ942K MB510

https://www.yoycart.com/Product/551538695332/ (https://www.yoycart.com/Product/551538695332/)
Title: Re: Component Identification - PJ1499 LZ
Post by: fzabkar on March 25, 2023, 03:38:56 pm
Quote from: killingtime on March 25, 2023, 12:34:37 pm
Found a website that says it could be a schottky diode. Equiv: PJ942K MB510

https://www.yoycart.com/Product/551538695332/ (https://www.yoycart.com/Product/551538695332/)

That's an MB510 diode:

https://www.panjit.com.tw/upload/datasheet/MB510-AU.pdf (https://www.panjit.com.tw/upload/datasheet/MB510-AU.pdf)

"PJ" is Panjit International. "1499" must be some kind of date and batch code. "LZ" is the part ID.

PJSD24TS, Panjit, TVS diode, 120W, 24V, marking LZ, SOD-523:
https://www.panjit.com.tw/en/Product/downloadPDF/PJSD24TS (https://www.panjit.com.tw/en/Product/downloadPDF/PJSD24TS)
ttps://datasheet.lcsc.com/lcsc/1811021612_PANJIT-International-PJSD36TS-R1-00001_C304458.pdf (http://ttps://datasheet.lcsc.com/lcsc/1811021612_PANJIT-International-PJSD36TS-R1-00001_C304458.pdf)