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DS21Q55

34. AC TIMING PARAMETERS AND DIAGRAMS

Capacitive test loads are 40pF for bus signals, 20pF for all others.

34.1 Multipexed Bus AC Characteristics

AC CHARACTERISTICS–MULTIPLEXED PARALLEL PORT (MUX = 1) (0°C to +70°C; VDD = 3.3V ± 5% for DS21Q55;

-40°C to +85°C; VDD = 3.3V ± 5% for DS21Q55N)

PARAMETER

SYMBOL

MIN

TYP

MAX

UNITS

NOTES

Cycle Time

TCYC

200

 

 

ns

 

Pulse Width, DS Low or RD*

PWEL

100

 

 

ns

 

High

 

 

 

 

 

 

Pulse Width, DS High or RD*

PWEH

100

 

 

ns

 

Low

 

 

 

 

 

 

Input Rise/Fall Times

TR, tF

 

 

20

ns

 

R/W* Hold Time

TRWH

10

 

 

ns

 

R/W* Setup Time Before DS

TRWS

50

 

 

ns

 

High

 

 

 

 

 

 

CS* Setup Time Before DS,

tCS

20

 

 

ns

 

WR* or RD* Active

 

 

 

 

 

 

CS* Hold Time

tCH

0

 

 

ns

 

Read Data Hold Time

TDHR

10

 

50

ns

 

Write Data Hold Time

TDHW

5

 

 

ns

 

Muxed Address Valid to AS or

TASL

15

 

 

ns

 

ALE Fall

 

 

 

 

 

 

Muxed Address Hold Time

TAHL

10

 

 

ns

 

Delay Time DS, WR*, or RD*

TASD

20

 

 

ns

 

to AS or ALE Rise

 

 

 

 

 

 

Pulse Width AS or ALE High

PWASH

30

 

 

ns

 

Delay Time, AS or ALE to DS,

TASED

10

 

 

ns

 

WR* or RD*

 

 

 

 

 

 

Output Data Delay Time from

TDDR

 

 

80

ns

 

DS or RD*

 

 

 

 

 

 

Data Setup Time

TDSW

50

 

 

ns

 

See Figures 37-1 to 37-3

 

 

 

 

 

 

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Please contact telecom.support@dalsemi.com or search http://www.maxim-ic.com for updated

information.

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Maxim DS21Q55 specifications AC Timing Parameters and Diagrams, Parameter Symbol MIN TYP MAX Units