User manual

Preventive Maintenance
ProMaster 2500 User Manual 5-5
•
Security fuse check
—Some devices have a security fuse feature that,
when programmed, prevents the reading of the main fuse pattern.
Some semiconductor manufacturers allow the programmer to check
the fuse before trying to program the fuses in the main array. If the
security fuse is blown, the device cannot be read or programmed and
TaskLink displays
SECURITY FUSE VIOLATION
.
•
Check silicon ID
—Many devices have internal identification
numbers (an electronic I.D.) that the PE can read. These numbers
allow the PE to determine the manufacturer of the device, the part
number, and the type. For example, if the Task identifies a device
from manufacturer A (requiring a specific programming algorithm)
and a tube of devices from manufacturer B (requiring a different
programming algorithm) is mistakenly inserted, TaskLink displays
ELECTRONIC ID ERROR
and the handler routes these devices to an
output tube specified in the Task setup before a programming pulse
has been applied.
•
Blank check
—This checks to ensure that all the fuses in the device’s
main array are blank (unprogrammed). Most devices allow the
programming cycle to continue even when a programmed fuse has
been detected. If the Task is configured to reject devices with any
programmed fuses, TaskLink displays
NON-BLANK
and the handler
routes these devices to an output tube specified in the Task setup.
•
Illegal bit check
—Some devices that are programmable by the
system are not electrically erasable. The PE can erase only electrically
erasable devices. The PE checks each fuse to make sure the fuse is
unprogrammed (blank). If the PE finds a programmed fuse in the
device and its RAM data indicates that the fuse should be
unprogrammed, TaskLink displays
ILLEGAL BIT
. Most erasable/
programmable devices cannot be erased in the socket. The system
routes these devices to an output tube specified in the binning setup.
If the device passes all these pre-programming tests, the PE begins
programming, using the manufacturer’s programming algorithm. Some
algorithms require that the PE apply a single programming pulse to the
fuse, and then immediately check the fuse to see if it’s programmed
before continuing. This type of algorithm normally specifies a maximum
number of times that the PE can try to program a fuse. If the fuse fails to
program after the maximum number of pulses have been applied,
TaskLink fails the device and displays
PROGRAM FAIL
.