Power NPN transistor N344AB

I couldn't find the A or AB version of it.

Some indication comes from an earlier version of it. Instead of an NPN power transistor it looks like a PNP low power VHF switching transistor. Did they change it a LOT when they went to the AB designation?

Name: 2N344

Material of 2N344 transistor: Ge Structure of 2N344 transistor: pnp Maximum collector power dissipation of 2N344 transistor (Pc): 20mW Maximum collector-base voltage of 2N344 transistor (Ucb): 5V Maximum collector-emitter voltage of 2N344 transistor (Uce): 5V Maximum emitter-base voltage of 2N344 transistor (Ueb): - Maximum collector current of 2N344 transistor (Ic max): 5mA Maximum junction temperature of 2N344 transistor (Tj): 85=EF=BF=BDC Transition frequency of 2N344 transistor (ft): 20MHz Collector capacitance of 2N344 transistor (Cc), Pf: 12 Forward current transfer ratio of 2N344 transistor (hFE), min/max:

22T Manufacturer of 2N344 transistor: CSR Case of 2N344 transistor: TO23 Application of 2N344 transistor: VHF, Low Power

Den 01.01.2011 12:45, skrev Greegor:

Hi

This ought to be a high power NPN transistor. The heater blower motor is a powerful fan fused with a dedicated 40A fuse, so I suspect the current flowing through the transistor is at least 30A at full speed.

The collector is connected to the fan and the emitter is connected to ground. When I short-circuit collector and emitter the blower runs at full speed.

Can it be some kind of OEM type number?

regards Geir

Try BUW48.....

Den 01.01.2011 13:17, skrev TTman:

Ok...

Fact or (wild) guess?

I don't want to put in something which will be fried or might fry the CAN bus circuitry....

Geir

can't see that you need anything special.... this one is rated at 40 amps.... there must be plenty more out there.

Jamie

Maybe

Jamie

Nice catch! Shorting C and E by the OP to run the fan would actually be shorting D and S. I think the OP needs to look more at the base/gate drive part of the circuit, now.

Jon

... assuming it was a TO-220/TO-247 style package.

Did the OP say?

Jon

Never mind. I just looked at the posted image.

Jon

Is the original a FET? It looks like 4 of the suggested replacements are FET's.

H80NF55-08 replaced with a HUF75337P3

HUF75337P3 75A/ 55V/ 0.014 Ohm/ N-Channel UltraFET Power MOSFETs

STH80NF55 has TO-218 case

STH80NF55-08 MOS-N-FET for klimatronic regulators, rds=3D0,008Ohm. TO247 G D S D 16p

IRFP064N TO-247 case

Check out other comments at the links for other details that might be important.

mrjolly Peugeot Owned: 406 Posted: Mon Aug 03, 2009 2:22 am

Found the problem was the fan resistor, I also found a previous entry which i have added to, had some helpful info :- The blower fan resistor unit, the one witht the aluminium fins on it is located in the ducting to the right of the fan under the glove box. When i finally got this unit out I was surprised at the large amount of electronics in it! There is one large 'transistor' clipped to the aluminium heat sink and it looked very tired, it was also oozing white goo!!. Electronic things that get hot often fail. After some difficulty in de-soldering it, I bought a simimilar transistor from Maplin Electronics for =A31.92 adjusted the pins and soldered it back into the board after cleaning up the heat sink and now everything works ( no driving in a force ten gale !!!). For interest, the transistor that was faulty was a

H80NF55-08. I replaced it with a HUF75337P3 [ FET ]

------------------------------------------------------------------

that has similar characteristics. Many thanks for your help.

Does it not work at all? If not locate where the motor is and with key on and fan on high..tap on it-if the blower motor starts its the motor itself thats defective-if it only works on high speed its most likely a bad resistor. Depending on age of it, this can be a common problem.

OP slampen: Have you tested the blower motor itself? Peugeot 406 chit chat says that it's common for the blower motor itself to go out, and a bad one commonly revives temporarily when the motor is tapped or whacked.

Have you tested the blower motor itself?

Do you even READ a thread EVER... at all? You stupid f*ck?

He showed us the failed part diagnostic, which proved the proper function of the "blower motor itself".

Your lack of logic matches your incapacity to make "assessments" in any other realm as well. A root cause, in fact.

You still need to receive yours, obviously. *THWACK!* Direct Hit firing solution resolved!

Oh, darn! Usenet has no "Fire for effect" mode, or you would be vaporized by the laser from the "Real Genius" film! Or at least whopped upside da haed with a baseball bat or ancient shillelagh.

The darndest thing though... if device number two is used, the urge to continue beyond the first whoppin' is irresistible!

Bwuahahahahahaha!

You're a brainless wonder. It would be fun to open up that skull cavity and prove it to be true.

Ever see the first episode of "Lexx"?

Bwuahahahahahahahahahahahahahahahahahahahahahaa!!!

The OP did write, "When I short-circuit collector and emitter the blower runs at full speed." Which, given Jamie's earlier comments and your additional post, looks like an N-FET and not an NPN, where the OP was shoring D to S, not C to E.

Jon

I hadn't even looked at your image, but Jamie had the wisdom to do that. I think Jamie has nailed it. If so, they are cheap and broadly in stock. This being the cheapest I could find quickly:

To be absolutely sure before trying anything else, if you are still worried, you may need to take a measurement at pin 1 and see what you observe regarding the driver when the system attempts to turn the fan on and off and post the information. Or else observe and comment what you see connected to pin 1.

But it looks as though what you have is more likely an N-MOSFET. Particularly considering the discussion that Greegor uncovered.

Jon

Clearly that particular transistor was not used! If indeed a NPN was used, perhaps a 2N3055 might be useful; if a PNP the 2N3054 is the compliment (if i remember right). As far as the package goes, one would think almost any power transistor in same/similar package would do...if of right flavor.

That leading '2', or lack thereof, makes a lot of difference. It's probably a house number for whoever made the controller in the first place.

You could try putting in a regular power NPN and hope that it works. What makes you think it's not an N-channel FET?

--
http://www.wescottdesign.com

If it's just a simple pwm, then NPN or N fet should work..... so long as there's a base resistor for NPN mode.

as

How do these things provide a low or medium speed?