NEC 78K0 User Manual page 541

CHAPTER 30 ELECTRICAL SPECIFICATIONS (STANDARD PRODUCTS, (A) GRADE PRODUCTS)
(2) Read/write operation
= −40 to +85°C, 2.7 V ≤ V
(T
A
Parameter
ASTB high-level width
Address setup time
Address hold time
Data input time from address
Address output time from RD↓
Data input time from RD↓
Read data hold time
RD low-level width
Input time from RD↓ to WAIT↓
Input time from WR↓ to WAIT↓
WAIT low-level width
Write data setup time
Write data hold time
WR low-level width
Delay time from ASTB↓ to RD↓
Delay time from ASTB↓ to WR↓
Delay time from RD↑ to ASTB↑ at
external fetch
Address hold time from RD↑ at
external fetch
Write data output time from RD↑
Write data output time from WR↓
Address hold time from WR↑
Delay time from WAIT↑ to RD↑
Delay time from WAIT↑ to WR↑
Caution T can only be used at 0.238
CY
Remarks 1. t = T /4
CY CY
2. n indicates the number of waits.
3. C = 100 pF (C
L
ASTB pins.)
≤ 5.5 V, 2.7 V ≤ AV
= EV
DD DD
Symbol Conditions
t
ASTH
t
ADS
t
ADH
t
ADD1
t
ADD2
t
RDAD
t
RDD1
t
RDD2
t
RDH
t
RDL1
t
RDL2
t
RDWT1
t
RDWT2
t
WRWT
t
WTL
t
WDS
t
WDH
t
WRL1
*
t
ASTRD
t
ASTWR
t
RDAST
t
RDADH
t
RDWD
t
WRWD
t
WRADH
t
WTRD
t
WTWR
µ
s (MIN).
indicates the load capacitance of the AD0 to AD7, A8 to A15, RD, WR, WAIT, and
L
User's Manual U15947EJ2V0UD
≤ V
, V = EV = AV
REF DD SS SS
MIN.
0.3t
CY
20
6
(2 + 2n)t
(3 + 2n)t
0
(2 + 2n)t
(3 + 2n)t
0
− 33
(1.5 + 2n)t
CY
− 33
(2.5 + 2n)t
CY
(0.5 + 2n)t + 10
CY
60
6
− 15
(1.5 + 2n)t
CY
6
− 15
2t
CY
− 15
0.8t
CY
− 15
0.8t
CY
40
10
− 15
0.8t
CY
0.8t
CY
0.8t
CY
= 0 V)
SS
(1/2)
MAX. Unit
ns
ns
ns
− 54
ns
CY
− 60
ns
CY
100 ns
− 87
ns
CY
− 93
ns
CY
ns
ns
ns
− 43
t
ns
CY
− 43
t
ns
CY
− 25
t
ns
CY
(2 + 2n)t ns
CY
ns
ns
ns
ns
ns
1.2t ns
CY
1.2t + 30 ns
CY
ns
60 ns
1.2t + 30 ns
CY
2.5t + 25 ns
CY
2.5t + 25 ns
CY
541