UV EPROM Eraser

[granddad]

I have been using flash and EEproms for various projects, but if speed <200ns is not a issue then I could save $$$ , and recycle some uveprom... at first thought seems a good idea, as i have a bag or various sizes , the drawback is the erasing , I had a eraser , but the bulb gave up the ghost years ago and the unit was from the 70's. Last week found a simple and cheap solution (YT link), a small hand held UVC lamp. says 260nm wavelength .there is no timer, the switch is held on for 3 sec, then pushed again for off.
I was a little skeptical , but a test today , worked fine , a 27C64 covered by the lamp for 10 minutes worked fine , the unit shown runs from a usb supply or 4 AAA batteries, draws about 300ma. Care has to be taken where the UV light is shone not into eyes or to skin . for that reason I will make a box for it , it will cover 2 x 28 or 2 x 32 pin devices and they fit perfectly against the UV light source .

 

[For The Popcorn]

I wonder if one of the UV lights for nail polish curing would do the job? They are available in the $5 range.

 

[granddad]

I wonder if one of the UV lights for nail polish curing would do the job?

Possibly , my test on a 27C64 was 10mins, with chip window touching the glass of the lamp Your picture They look like UV leds ?

 

[For The Popcorn]

Yes, UV LEDs. Does EPROM erasing require UVC? If so, nevermind

I saw a UVC light on the shelf with lamps at a thrift store recently, with a very smart warning label. I asked to talk to the manager and explained that "Oh look at the pretty blue light!" was going to cause eye damage to someone, and it shouldn't be on the shelf with lamps and a power outlet.

I was almost surprised when they took my comments seriously and pulled it from the shelf.

 

[granddad]

Does EPROM erasing require UVC?

From what i understand yes they do , UVC is 250 ish nanometer this lamp is a glass tube(2), possibly mercury based, and 4 watts, not sure how dangerous though,

 

[AnalogKid]

I was a little skeptical , but a test today , worked fine , a 27C64 covered by the lamp for 10 minutes worked fine ,

Way back when, I used EPROMs as logic arrays in several projects, including a TV sync generator and a power system controller for an ambulance. My first-love programmable device. I still have some parts, the programmer, and the eraser. I haven't fired up the eraser in decades, but this is a great idea for a replacement.

ak

 

[atferrari]

At the time I implemented my very first design with a PIC (16C57), I bought four or maybe five of those chips.

Kept them in a busy merry go round including a germicide tube and its ballast in a box during debugging sessions. Worked OK albeit I cannot say how I controlled the timing.

 

[Diver300]

Many years ago, I erased some EPROMs with a light box designed for UV-sensitive PCBs. I think that took overnight to completely erase the EPROMs.