Specifications, Applications, Maintenance – UVP DE-4 User Manual
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Specifications
The DE-4 EPROM Erasing System has the following specifications:
Size:
9”L x 3.7”W x 2.6”H (23 x 9.4 x 6.6 cm )
Weight:
1.5 lbs (0.7 kg )
Tray Size:
2.9” x 2.5” (7.4 x 6.4 cm)
Capacity:
8 (24 pin EPROM)
Power:
100 to 115V, 50 to 60 Hz
215 to 250V, 50 to 60 Hz
Erase Time:
See Table 1
Applications
Intensity
The Model DE-4 EPROM Eraser System produces an intensity of approximately
6800 uW/cm
2
at the center of the drawer with the original or new replacement
tube. This intensity varies at different locations over the pad area of the chip
arrangements. Lamp intensity decreases as the lamp ages. A representative inten-
sity for a lamp that has been operated for the 1000 hours is 50% of new. This
varies according to the operation cycles and other considerations.
Erase Time
An EPROM requires a given amount of 254nm irradiance for a minimum amount of
time to obtain a complete erasure. In this system, two factors will determine the
erase time. One is the required erase energy of the EPROM itself while the other
is the location of the EPROM in the incidence energy field.
The erase energy is specified by the EPROM manufacturer in Joules/cm
2
or Watt-
Seconds/cm
2
and varies between EPROMs and manufacturers. The specific value
for a given EPROM can be obtained from the manufacturer’s literature.
Maintenance
WARNING: Do not attempt to disassemble this unit while plugged into the AC
outlet. Failure to unplug the unit from the AC outlet while disassembling the unit
will result in an electrical shock hazard.
WARNING: Do not attempt to operate this unit in the disassembled condition.
Operating the unit in the disassembled condition may expose the eyes and skin to
shortwave UV that is harmful to the unprotected eyes and skin.
Tube Replacement
To replace the tube, first unplug the EPROM Eraser from the AC outlet. Turn the
unit upside down on the bench and remove the three screws from the bottom. Lift
Figure 1
Knowing the erase energy from the manufacturer’s literature and the layout pat-
tern of the EPROMs in the drawer, refer to Table 1 to obtain the required erase
time. Example: if you have five EPROMs arranged in the drawer per Figure 1,
and their erase energy is 10 W-Sec/cm
2
, the required time to complete the erasure
is 29 minutes.
For numbers of EPROMs not covered in Figure 1, very close estimates of the
required erase time can be obtained by interpolating between the numbers used in
the Table 1. In the event, the manufacturer’s specified erase energy is not one of
the three listed in Table 1, then the required erase time can be computed in the
following manner.
Suppose the manufacturers specified erase energy is 20 W-Sec/cm
2
(Joules/cm
2
)
and you are erasing one EPROM. On Table 1 you will note that one EPROM
requiring 15 W-Sec/cm
2
erase energy, requires 37 minutes for erasure. To com-
pute the erase time, multiply 37 (minutes) by 20 (W-Sec/cm
2
). This will give you
the erase time (in minutes) required for this new EPROM and any quantity of
EPROMs that will fit within the drawer. In the calculation, it is best to choose the
erase time (in minutes) most closely corresponding to the UV erase energy needed
for the appropriate number of EPROMs you wish to erase at any one time.
Erase time for:
Number
6 W-Sec/cm
2
10 W-Sec/cm
2
15 W-Sec/cm
2
of
EPROM
EPROM
EPROM
EPROMs
(Minutes)
(Minutes)
(Minutes)
1
15
25
37
4
16
27
40
5
18
29
42
8
2 1
3 4
5 1
Table 1
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