Datasheet

Memory Characteristics
MC68HC908JL3E Family Data Sheet, Rev. 4
Freescale Semiconductor 145
16.13 Memory Characteristics
Table 16-11. Memory Characteristics
Characteristic Symbol Min Max Unit
RAM data retention voltage
V
RDR
1.3 — V
Flash program bus clock frequency — 1 — MHz
Flash read bus clock frequency
f
Read
(1)
1. f
Read
is defined as the frequency range for which the Flash memory can be read.
32k 8M Hz
Flash page erase time
t
Erase
(2)
2. If the page erase time is longer than t
Erase
(Min), there is no erase-disturb, but it reduces the endurance of the Flash mem-
ory.
1—ms
Flash mass erase time
t
MErase
(3)
3. If the mass erase time is longer than t
MErase
(Min), there is no erase-disturb, but it reduces the endurance of the Flash
memory.
4—ms
Flash PGM/ERASE to HVEN set up time
t
nvs
10 — μs
Flash high-voltage hold time
t
nvh
5—μs
Flash high-voltage hold time (mass erase)
t
nvh1
100 — μs
Flash program hold time
t
pgs
5—μs
Flash program time
t
PROG
30 40 μs
Flash return to read time
t
rcv
(4)
4. t
rcv
is defined as the time it needs before the Flash can be read after turning off the high voltage charge pump, by clearing
HVEN to 0.
1—μs
Flash cumulative program hv period
t
HV
(5)
5. tHV is defined as the cumulative high voltage programming time to the same row before next erase.
t
HV
must satisfy this condition: t
nvs
+ t
nvh
+ t
pgs
+ (t
PROG
× 32) ≤ t
HV
max.
—4 ms
Flash row erase endurance
(6)
6. The minimum row endurance value specifies each row of the Flash memory is guaranteed to work for at least this many
erase / program cycles.
— 10k — cycles
Flash row program endurance
(7)
7. The minimum row endurance value specifies each row of the Flash memory is guaranteed to work for at least this many
erase / program cycles.
— 10k — cycles
Flash data retention time
(8)
8. The Flash is guaranteed to retain data over the entire operating temperature range for at least the minimum time specified.
—10—years