MM58274C National, MM58274C Datasheet - Page 3

• Manufacturer Part Number: MM58274C
• Description: Microprocessor Compatible Real Time Clock
• Manufacturer: National

AC Switching Characteristics
READ TIMING DATA FROM PERIPHERAL TO MICROPROCESSOR V
WRITE TIMING DATA FROM MICROPROCESSOR TO PERIPHERAL V
Note 3 Except for special case restriction with interrupts programmed max read strobe width of control register (ADDR 0) is 30 ms See section on Interrupt
Programming
Note 4 All timings measured to the trailing edge of write strobe (data latched by the trailing edge of WR)
Note 5 Input test waveform peak voltages are 2 4V and 0 4V Output signals are measured to their 2 4V and 0 4V levels
Note 6 Write strobe as used in the Write Timing Table is defined as the period when both chip select and write inputs are low ie WS
strobe commences when both signals are low and terminates when the first signal returns high
Note 7 Read strobe as used in the Read Timing Table is defined as the period when both chip select and read inputs are low ie RS
Note 8 Typical numbers are at V
Symbol
t
t
t
t
t
t
t
t
Symbol
t
t
t
t
t
t
t
t
AD
CSD
RD
RW
RA
CSH
RH
HZ
AW
CSW
DW
WW
WCS
WA
WD
AWS
Address Bus Valid to Data Valid
Chip Select On to Data Valid
Read Strobe On to Data Valid
Read Strobe Width (Note 3 Note 7)
Address Bus Hold Time from Trailing Edge
of Read Strobe
Chip Select Hold Time from Trailing Edge
of Read Strobe
Data Hold Time from Trailing Edge
of Read Strobe
Time from Trailing Edge of Read Strobe
Until O P Drivers are TRI-STATE
Address Bus Valid to Write Strobe
(Note 4 Note 6)
Chip Select On to Write Strobe
Data Bus Valid to Write Strobe
Write Strobe Width (Note 6)
Chip Select Hold Time Following
Write Strobe
Address Bus Hold Time Following
Write Strobe
Data Bus Hold Time Following
Write Strobe
Address Bus Valid Before
Start of Write Strobe
CC
e
5 0V and T
Parameter
Parameter
A
e
25 C
3
Min
400
250
400
250
100
DD
70
DD
0
0
Min
70
e
0
0
e
T
5V
A
T
5V
A
e b
g
Specification
e b
g
Commercial
0 5V C
Specification
0 5V
Commercial
40 C to
Typ
125
100
220
40 C to
95
35
20
Typ
390
140
140
160
L
e
a
100 pF
a
85 C
85 C
Max
Max
650
300
300
250
DC
e
e
CS
CS
a
a
WR Hence write
RD
Units
Units
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns