UVP DE-50 - Manual (Page 2)

Introduction - Ultraviolet Light
The invisible band of radiation just beyond the violet end of the visible spectrum is called ultraviolet light. That
spectrum includes the wavelength that is instrumental in erasing EPROMs: 253.7nm, frequently referred to as
approximately 254nm or 2537 Angstrom. The radiant incidence of this energy at the location of the EPROM is
a function of the distance between the light source and the EPROM and the geometry of the light source. The
DE-50 EPROM Erasing System design optimizes these elements to give the best possible performance.
Design Features
The DE-50 EPROM Erasing System is designed to provide safe tools for exposure of EPROMs to shortwave
ultraviolet radiation. Features include:
•
Superior reflectors that maximize UV output and distribution
•
A 60 minute automatic shut-off timer
•
A safety interlock prevents UV exposure to personnel
•
PC board compatibility
•
Long life, high intensity UV tubes for minimum erase times
•
A viewport for each UV tube to observe tube operation
•
A conductive foam pad to eliminate electrostatic build up
•
A rugged metal housing
Specifications
The DE-50 EPROM Eraser has the following specifications:
Capacity: 50 EPROMs (24 pin type)
Size: 4.11 in. H (10.44 cm) x 11.70 in. W (29.72 cm) x 13.44 in. D(34.14 cm)
Drawer Depth: 1.375 in. (3.49 cm)
Weight: 13.75 lbs (6.25 kg)
Power: 100V, 50 Hz, 1 Amp
110V, 60 Hz, 1 Amp
230V, 50 Hz, 1 Amp
Operating Instructions
Set-Up Procedures
1. Slide the tray out unit it stops.
2. Press the EPROMs to be erased down into the foam pad. As the radiant incidence is somewhat greater
near the center than the edges, place the EPROMs more towards the center unless the full capacity of the
unit is to be used.
3. Close the drawer all the way. (The unit has a safety interlock and will not operate if the drawer is open.)
4. Plug in the unit and set the timer for the desired erase time. When the timer is set and the unit is in
operation, the five view ports will glow green without emitting harmful shortwave radiation.
Erase Time and Exposure Considerations
Erase time is inversely proportional to the radiant incidence from the lamp at the EPROM surface. Radiant
incidence from the lamp at the EPROM surface varies with EPROM location in the unit and with lamp
temperatures, running time and individual lamp differences. The following table lists recommended times to
erase all EPROMs placed in a new unit. Most EPROMs require a dosage of 15 W-sec/cm
2
for erasure.
However, erasure requirements vary from 6 W-sec/cm
2
to 25 W-sec/cm
2
. Check with the EPROM
manufacturer for specific recommended dosages.
Nominal # of Typical EPROM Erasure
Intensity 24 Pin Time in Minutes
Model
μ W/cm 2
EPROMs 15 W-sec/cm
2
DE-50 12,000 1 - 50 5.9 *