Digital Timing Characteristics

The following specifications apply for V

unless otherwise specified. Boldface limits apply for T

Symbol (See

Figures 10, 11, 12)

Parameter

Conditions

Typical

(Note 10)

Limits

(Note 11)

Units

1, 3

CS or Address Valid to ALE Low Set-Up

Time

40

ns (min)

2, 4

CS or Address Valid to ALE Low Hold

Time

20

ns (min)

5

ALE Pulse Width

45

ns (min)

6

RD High to Next ALE High

35

ns (min)

7

ALE Low to RD Low

20

ns (min)

8

RD Pulse Width

100

ns (min)

9

RD High to Next RD or WR Low

100

ns (min)

10

ALE Low to WR Low

20

ns (min)

11

WR Pulse Width

60

ns (min)

12

WR High to Next ALE High

75

ns (min)

13

WR High to Next RD or WR Low

140

ns (min)

14

Data Valid to WR High Set-Up Time

40

ns (min)

15

Data Valid to WR High Hold Time

30

ns (min)

16

RD Low to Data Bus Out of TRI-STATE

30

10

ns (min)

70

ns (max)

17

RD High to TRI-STATE

R

Ω

30

10

ns (min)

110

ns (max)

18

RD Low to Data Valid (Access Time)

30

10

ns (min)

95

ns (max)

20

Address Valid or CS Low to RD Low

20

ns (min)

21

Address Valid or CS Low to WR Low

20

ns (min)

19

Address Invalid from RD or WR High

10

ns (min)

22

INT High from RD Low

30

10

ns (min)

60

ns (max)

23

DMARQ Low from RD Low

30

10

ns (min)

60

ns (max)

Electrical Characteristics

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is

functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed

specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test

conditions.

Note 2: All voltages are measured with respect to GND, unless otherwise specified.

The 20 mA maximum package input current rating allows the voltage at any four pins, with an input current of 5 mA, to simultaneously exceed the power supply

voltages.

number given in the Absolute Maximum Ratings, whichever is lower.

Note 5: Human body model, 100 pF discharged through a 1.5 k

Ω resistor.

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