Electrical Specifications
22.17 Memory Characteristics
Table 22-17. Memory Characteristics
Characteristic
Symbol
Min.
Max.
Unit
V
VRDR
Data retention voltage
1.3
—
Number of rows per page
Number of bytes per page
8
Rows
Bytes
512
(1)
Read bus clock frequency
Page erase time
32k
20
8M
—
Hz
ms
fread
(2)
terase
(3)
Mass erase time
200
5
—
—
—
—
—
40
—
30
—
ms
µs
µs
µs
µs
µs
ns
ns
µs
tme
tnvs
tnvh
tnvh1
tpgs
tprog
tads
tadh
PGM/ERASE to HVEN setup time
High-voltage hold time
High-voltage hold time (mass erase)
Program hold time
5
100
10
20
20
—
1
Program time
Address/data setup time
Address/data hold time
Recovery time
(4)
trcv
(5)
Cumulative HV period
—
10k
10k
10
8
—
—
—
ms
thv
Row erase endurance(6)
Row program endurance(7)
Data retention time(8)
—
—
—
Cycles
Cycles
Years
1. fread is defined as the frequency range for which the FLASH memory can be read.
2. If the page erase time is longer than terase (Min.), there is no erase-disturb, but it reduces the endurance of the FLASH
memory.
3. If the mass erase time is longer than tme (Min.), there is no erase-disturb, but it reduces the endurance of the FLASH
memory.
4. It 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 logic 0.
5. thv is the cumulative high voltage programming time to the same row before next erase, and the same address can not be
programmed twice before next erase.
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.
7. The minimum row endurance value specifies each row of the FLASH memory is guaranteed to work for at least this many
erase/program cycle.
8. The FLASH is guaranteed to retain data over the entire operating temperature range for at least the minimum time
specified.
MC68HC908AP Family Data Sheet, Rev. 4
314
Freescale Semiconductor
FREESCALE [ Freescale ]
