Epson RTC-72421 B Clock User Manual


 
RTC - 72421 / 72423
Page - 6 MQ - 162 - 03
2. When ALE is fixed at V
DD
Write mode ( V
DD
=5 V
±
0.5 V, RTC-72421;Ta=
10
°
C to +70
°
C, RTC-72423;Ta=
40
°
C to +85
°
C )
Item Symbol Condition Min. Max. Unit
CS1 set-up time t
SU
(CS1) 1000
CS1 hold time th(CS1) 1000
Address set-up time before write t
SU
(A-W) 50
Address hold time after write th(W-A) 10 ns
Write pulse width tw(W) 120
Data input set-up time before write t
SU
(D-W) 80
Data input hold time after write th(W-D) 10
Write recovery time trec(W) 200
Read mode ( V
DD
=5 V
±
0.5 V, RTC-72421;Ta=
10
°
C to +70
°
C, RTC-72423;Ta=
40
°
C to +85
°
C )
Item Symbol Condition Min. Max. Unit
CS1 set-up time t
SU
(CS1) 1000
CS1 hold time th(CS1) 1000
Address set-up time before read t
SU
(A-R) 50
Address hold time after read th(R-A) 10 ns
Data output transfer time after read tpzv(R-Q) C
L
=150 pF 120
Data output floating transfer time after read tpvz(R-Q) 0 70
Read recovery time trec(R) 200
(1) Write mode
VIH2
tsu(CS1)
tsu(A-W)
tw(W)
VIH1
VIL1
VIH1
VIL1
VIH1
VIL1 VIL1
VIH1
th(W-A)
VIH1
VIL1
VIH1
VIL1
tsu(D-W)
th(W-D)
th(CS1)
VIH2
CS1
A0 to A3
CS0
D0 to D3
WR
(Input)
(2) Read mode
VIH2
tsu(CS1)
tsu(A-R)
VIH1
VIL1
VIH1
VIL1
VIH1
VIL1 VIL1
VIH1
th(R-A)
VOH
VOL
VOH
VOL
tpzv(R-Q)
tpvz(R-Q)
th(CS1)
VIH2
CS1
A0 to A3
CS0
D0 to D3
RD
(Output)
(3) Read/write recovery mode
VIH1VIH1
RD,WR
trec(R/W)