The exploding LA-light

[Aren]

Hi,

Today I received a fresh supply of parts, so I finished my LA-light build (Lowstar's vero layout). At first I tried powering it using a 9V battery, but noticed the LEDs barely had enough power to light up, so I improvised a walwart connection and tried a 30V DC supply. It worked fine, so I went back to the workbench and installed a permanent DC jack. I powered it up, saw the LEDS light up like it's Christmas (oh well... they got the date right), heard a bang, and noticed that the TL072 literally exploded  . I figured two parts must have touched each other, so I made sure no wires were interconnecting, put a TL082 in the socket, and the scenario just repeated itself. Anyway, until I get my shipment from smallbear I'm all out of opamps, but I want to make sure the circuit is fine before I fry a new load of ICs  Any way to do it without stacking it with another chip?

Thanks,

Oren

[Johan]

sounds like you have either the opamp in the wrong way or have the powersupply poles confused... opamp's doesn't just blow up...check your opamp orientation and powersupply...
j

[Phorhas]

With 30 volts going into a TL072, you should probably use a split-supply to get +15 and -15 volts, rather than +30 volts with a single supply. the maximum supply voltage for a TL072 IIRC is around +/-18V.

Cheers

[MartyMart]

OOOPS !!
Yup, single supply of 30v is WAY too much, as stated maximum is a +/- 18v supply.
I have no problems with my LA-Light running at either 9v or 12v.
MM.

[Aren]

I was sure someone said that he uses a 30V supply with it (after all, it's actually +-15, since it is split. Isn't it?)

[moro]

Do you have photos of the exploded 072?

[Aren]

Here are his remains, lying on the work bench  Right next to him you can see the TL082, which did not explode so dramatically...
The conclusion may be that the 072 is better for special effects 

http://picasaweb.google.com/oren.steinitz/MyPictures/photo#5147261364927359954

By the way - the DC jack was indeed connected the wrong way  . I Hate those things...

[PerroGrande]

Wow!  That thing popped big time!   

[RedHouse]

Dang Chinese plastic! in the good-'ol-days plastic used to just let out a puff of smoke and that was all she wrote. 

Imagine pickin a chunk o that out yer eye. 

Now that reminds me of a capacitor story, ...but that was an amp, so never mind.
(Electrolytic caps can explode violently with reverse polarity also)

[moro]

Wow. Pretty cool. Kind of scary.