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Forum Index : Microcontroller and PC projects : Can anyone point me at the correct SMD fuse ?
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phil99 Guru  Joined: 11/02/2018 Location: AustraliaPosts: 2611 |
C3518 is short for 2SC3518. Bipolar switching / audio transistor, From data sheet:- Current Gain hFE = 100 to 400 VCE(SAT) = 0.09V (TYP.) Absolut Max. Ratings VCB0 = 60V VCE0 = 60V VBE0 = 7V IC (DC) = 5A Total Power Disipation = 2.0 W (TA=25C) It could be used as a switch, switching regulator or linear reg. There is a zenner diode (ZD302) near by, suggesting a linear reg. A circuit diagram is needed. If the PCB is only double sided you can trace that part of it your self, from the power socket to the 5V and 15V rails. Then we can be of more help. Re fuse ratings. The marked current is the continuous operating current. The current at which it will blow depends on the type and time at the elevated current. Eg a tinned copper wire type will usually sustain 200% of rated current for 1 min. Re power supply rating. If it is a transformer & rectifier type the marked current is the max. you can draw from it without over heating, not the max. it can deliver. A 300 mA unit may deliver up to 2 amps into a short. Thus the exact fuse rating is not that important. The Goldilocks zone may be wide. |
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thwill Guru Joined: 16/09/2019 Location: United KingdomPosts: 4302 |
Thank you to everyone who has offered suggestions, I've decided this one can go back on flea bay for someone more experienced to try their luck with; I was struggling to find a memory card for it anyway. FYI with a new (1A) fuse installed it was drawing 0.85 A from my bench power supply and blowing the fuse (3 times) after about 5 mins. Best wishes, Tom MMBasic for Linux, Game*Mite, CMM2 Welcome Tape, Creaky old text adventures |
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