Build an eprom eraserr for about $7

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Build an eprom eraserr for about $7

Post by darknezz19 » Fri May 08, 2015 8:48 am

Received some m27c322 eproms the other day but they were not blank unfortunately. Money is tight so it was either spend ~25 for one from the states or ~15 to get one frrom China in 30 days. I read that germicidal lamps are the same bulbs in an eraser, but how would I power one?

Found a 9w UV germicidal bulb for about $6.50 shipped. Looking around the interweb we saw other people using CFL ballasts to power florescent lights. Went to the local grocery store and bamo, 9w cfls for 2 bucks. I've heard the dollar store carries these sometimes too but no luck at my store. Pop that bad boy open and you got your ballast.

Now these things are designed with 4 leads, 2 to each end of the original florescent tube. This UV bulb only has two terminals, one on each end. The two extra terminals on the ballast are for a starting capacitor that isn't needed for modern florescent. You should see that two of the four terminals create a loop with the biggest capacitor on the board in between, these are the two you don't use. Wire up the remaining two terminals to your UV lamp and put a cord on it and you got yourself a UV eraser. Put the bulb in a box of some sort and have the ballast outside, you can even use a timer if you want to be fancy. That's it. I set it to 10 minutes and the chips were blank.

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Re: Build an eprom eraserr for about $7

Post by AaronE » Fri May 08, 2015 2:17 pm

can also use the Sonicare bases with UV sterilization. Takes about 2.5-3 cycles.

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Re: Build an eprom eraserr for about $7

Post by rainwarrior » Fri May 08, 2015 2:47 pm

You could just leave them out in the sun. I seem to recall estimates suggesting it would take about a week to full erase a typical UV-EPROM.

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Re: Build an eprom eraserr for about $7

Post by sadponyguerillaboy » Sat Jun 20, 2015 10:03 am

You can use any UV-C bulb that emits within the 253.7nm / 254nm spectrum. I found a local bulb supplier and was able to buy the bulb and ballast for $20. But then again, you can order a complete eprom eraser from china on ebay for the same price, you just need to be able to wait a month or two for it to arrive. Also, as mentioned above, toothbrush sterilizers are good sources.

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