Charge pump with MAX1044 heat? got burned by the IC + melted breadboard :(

Started by add4, January 08, 2012, 03:06:10 AM

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add4

So i was playing around with the max1044 on breadboard. Basically i wanted to do a +9v -9v supply.
I breadboarded it, it worked, so i thought, hey, i'm going to test that charge pump thing that people use on the valve powered ODs and see if i can get 30-40 volts out of nine, and use my DMM to probe around and see if my understanding of the circuit work is good. Since everything was plugged in and powered, and i usually probe around and touch the pcbs without problems, even with power plugged it, i didn't bother to unpower the breadboard before making the changes.

So if i followed madbean road rage schematic : http://www.madbeanpedals.com/projects/RoadRage/docs/RoadRage.pdf. for the +9v -9v thing i had only : IC, D3, D4, C3, C4, C5 plugged in. To get the first stage of the charge pump made, I removed C5 and D4, and added C1. I was lowering my hand to push D1 in position into the breadboard while i felt heat from the circuit.
curious, i touched a few components, nothing, finally I touched the IC and i got burned as soon as i touched it.
so i immedialtely unpowered the breadboard. when i removed the IC, i saw that the plastic of the breadboard  melted from the ic heat..

I guess i did something wrong, but what is it? can somebody explain that to me? i'm a little bit afraid to try that charge pump thing again without knowing what to avoid .. i don't want to do anything dangerous.
Should the circuit be complete before it is plugged in? if yes, what are the 'blocks'? my guess is i should have at least put D1, D2 and C2 before plugging it in.
any advice?
thanks

CodeMonk

According to the datasheet, the MAX1044 provides 10mA of current.
You are probably trying to draw more that that.

frequencycentral

Best to connect everything up on the breadboard before applying power. I've got little melted patches on my breadboard too. Adds character.
http://www.frequencycentral.co.uk/

Questo è il fiore del partigiano morto per la libertà!