Could someone please tell me what this part is?

[cpposteve]

Hi all. Please see attached picture. Only markings are ST ELECTRONICS. and CBN Z440. Trying to work out what this part is so I can see if this is the issue my JBC soldering station. Thanks

[Manul]

I think it is TVS.

https://www.st.com/en/protection-devices/smbj36ca.html

[Andy Watson]

Possibly SMBJ36CA - bi directional 36V transient supressor.

https://www.st.com/resource/en/datasheet/smbj.pdf

[cpposteve]

Yes that would make sense. I’m guessing it’s used so if it sees a spike of anything over 40v in this case is shorts and absorbs the spike in voltage? Is this what they are used for? If so is it correct that it’s open circuit untill it goes over that thresh hold voltage? Thanks

[Manul]

I’m guessing it’s used so if it sees a spike of anything over 40v in this case is shorts and absorbs the spike in voltage? Is this what they are used for? If so is it correct that it’s open circuit untill it goes over that thresh hold voltage? Thanks

Yes, that is correct. Open circuit with some small capacitance and leakage.

[mayor]

Check out the topic around here about the smd markings database: https://smd.yooneed.one/

Code: [Select]

CBN	3KSMC58CATG	Fagor Electronica
DO-214AB	Transient voltage supressor

CBN	LN61CC5102M	Shanghai Natlinear Electronics
SOT-23	Voltage detector IC

CBN	LN61CC5102N	Shanghai Natlinear Electronics
SOT-343R	Voltage detector IC

CBN	LN61CC5102P	Shanghai Natlinear Electronics
SOT-89	Voltage detector IC

CBN	RP106N101D5	Ricoh
SOT-23-5	Linear voltage regulator IC

CBN	SMCJ16	Galaxy Semiconductor
DO-214AB	Transient voltage supressor

CBN	UM1550B-39	Union Semiconductor
SOT-89	Linear voltage regulator IC

CBN	XC6116B021MR	Torex Semiconductor
SOT-25	Voltage detector IC