hb28b128mm2 Renesas Electronics Corporation., hb28b128mm2 Datasheet - Page 85

• Manufacturer Part Number: hb28b128mm2
• Description: Multimediacard 16 Mbyte/32 Mbyte/64 Mbyte/128 Mbyte
• Manufacturer: Renesas Electronics Corporation.

The access time (t
• T
• T
The synchronous part of the access time is sum of the command frame length and some additional internal
cycles (N
time is T
maximum. The resulting memory access time t
which are required to access a byte of the memory field.
SAD
AAD
CMD
DAT
: The synchronous access time. This time defines the time of the maximum number of cycles
: The asynchronous access time to read a byte out of the memory field.
SAD
t
SAD
AT
Output
= T
= 0.8 µs. The asynchronous access delay of these Hitachi MultiMediaCards is T
Clock
= 16 cycles). At 20 MHz one cycle is 50 ns (1/f
Input
AAD
command frame
+ T
AT
) is divided into two parts:
SAD
: Invalid
Valid data
with
Timing Diagram of Data Input and Output
t
t
OH
IH
t
WH
T
SAD
T
SAD
= N
Access Time
AT
is the sum of both parts:
SAD
/f
t
t
PP
AT
PP
HB28H016/D032/B064/B128MM2
t
T
HL
AAD
PP
), multiplied with N
t
WL
t
ISU
t
OSU
response frame
Valid data
Valid data
Rev.5.0, Jan. 2003, page 83 of 88
t
LH
SAD
data
the resulting frame
V
V
V
V
V
V
AAD
IH
IL
IH
IL
OH
OL
= 300 µs