Datasheet

8
Atmel AT27C040 [DATASHEET]
0189J–EPROM–10/2012
7. Rapid programming algorithm
A 100μs CE pulse width is used to program. The address is set to the first location. V
CC
is raised to 6.5V and V
PP
is
raised to 13.0V. Each address is first programmed with one 100μs
CE pulse without verification. Then a
verification/reprogramming loop is executed for each address. In the event a byte fails to pass verification, up to ten
successive 100μs pulses are applied with a verification after each pulse. If the byte fails to verify after ten pulses have
been applied, the part is considered failed. After the byte verifies properly, the next address is selected until all have been
checked. V
PP
is then lowered to 5.0V and V
CC
to 5.0V. All bytes are read again and compared with the original data to
determine if the device passes or fails.
Figure 7-1. Rapid Programming Algorithm
Start
ADDR = First Location
V
CC
= 6.5V
V
PP
= 13.0V
V
CC
= 6.5V
V
PP
= 13.0V
Program One 100μs Pulse
Increment
Address
No
Last
ADDR?
Yes
ADDR = First Location
Increment
Address
X = 0
Last
ADDR?
No
Yes
Yes
No
Program One 100μs Pulse
Pass Fail
Verify
Byte
Increment
X = 10?
Fail
Pass
Compare
All Bytes
to Original
Data
Device
Failed
Device
Passed