Datasheet

Section 24 Electrical Characteristics
Rev. 3.00 Mar 17, 2006 page 908 of 926
REJ09B0283-0300
Notes: 1. Follow the program/erase algorithms when making the time settings.
2. Programming time per 128 bytes. (Indicates the total time during which the P bit is set
in flash memory control register 1 (FLMCR1). Does not include the program-verify
time.)
3. Time to erase one block. (Indicates the time during which the E bit is set in FLMCR1.
Does not include the erase-verify time.)
4. Maximum programming time
t
P
(max) = ∑ wait time after P bit setting (z)
N
i=1
5. The maximum number of writes (N) should be set as shown below according to the
actual set value of (z) so as not to exceed the maximum programming time (t
P
(max)).
The wait time after P bit setting (z) should be changed as follows according to the
number of writes (n).
Number of writes (n)
1 ≤ n ≤ 6 z = 30 µs
7 ≤ n ≤ 1000 z = 200 µs
(Additional programming)
Number of writes (n)
1 ≤ n ≤ 6 z = 10 µs
6. For the maximum erase time (t
E
(max)), the following relationship applies between the
wait time after E bit setting (z) and the maximum number of erases (N):
t
E
(max) = Wait time after E bit setting (z) × maximum number of erases (N)
7. Minimum number of times for which all characteristics are guaranteed after rewriting
(Guarantee range is 1 to minimum value).
8. Reference value for 25°C (as a guideline, rewriting should normally function up to this
value).
9. Data retention characteristic when rewriting is performed within the specification range,
including the minimum value.
24.7 Usage Note
The F-ZTAT and masked ROM versions both satisfy the electrical characteristics shown in this
manual, but actual electrical characteristic values, operating margins, noise margins, and other
properties may vary due to differences in manufacturing process, on-chip ROM, layout patterns,
and so on.
When system evaluation testing is carried out using the F-ZTAT version, the same evaluation
testing should also be conducted for the masked ROM version when changing over to that version.