Epson RTC-72421 A, RTC-72421 B, RTC-72423, RTC-72423 A Page, MQ - 162, 2. When ALE is fixed at VDD

RTC - 72421 / 72423

2. When ALE is fixed at VDD

Write mode

( VDD=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

tSU(CS1)

1000

CS1 hold time

th(CS1)

1000

Address set-up time before write

tSU(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

tSU(D-W)

80

Data input hold time after write

th(W-D)

10

Write recovery time

trec(W)

200

Read mode

( VDD=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

tSU(CS1)

1000

CS1 hold time

th(CS1)

1000

Address set-up time before read

tSU(A-R)

50

Address hold time after read

th(R-A)

10

ns

Data output transfer time after read

tpzv(R-Q)

CL=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

VIH2

CS1

tsu(CS1)

VIH1

th(CS1)

A0 to A3

VIH1

CS0

VIL1

VIL1

tsu(A-W)

tw(W)

th(W-A)

VIH1

VIH1

WR

VIL1

VIL1

th(W-D)

tsu(D-W)

D0 to D3

VIH1

VIH1

(Input)

VIL1

VIL1

(2) Read mode

VIH2

VIH2

CS1

tsu(CS1)

VIH1

th(CS1)

A0 to A3

VIH1

CS0

VIL1

VIL1

tsu(A-R)

th(R-A)

VIH1

VIH1

RD

VIL1

VIL1

tpvz(R-Q)

tpzv(R-Q)

D0 to D3

VOH

VOH

(Output)

VOL

VOL

(3) Read/write recovery mode

trec(R/W)

VIH1

VIH1

RD,WR

Page - 6 MQ - 162 - 03