DS1WM

15 of 15

TIMING SPECIFICATIONS

Symbol

Parameter

Conditions

Min

Max

Units

t

ADS

Address Strobe Width

Note 1,3

60

ns

t

AH

Address Hold Time

Note 1,3

0

ns

t

AR

Address Latch to Read

Note 1,3

60

ns

t

AS

Address Setup Time

Note 1,3

60

ns

t

AW

Address Latch to Write

Note 1,3

60

ns

t

DH

Data Hold Time

Note 1

30

ns

t

DS

Data Setup Time

Note 1

30

ns

t

ES

Enable Setup Time

Note 1

60

ns

t

HZ

RD to Floating Data Delay

Note 1

0

100

ns

t

LOW0

Write 0 Low Time, OD=0

Write 0 Low Time, OD=1

63

t

8

t

63

8

78.75

10

µs

t

LOW1

Write 1 Low Time, OD=0

Write 1 Low Time, OD=1

6

t

1

t

6

1

7.5

1.25

µs

t

PDH

Presence Detect High Normal

Presence Detect High Overdrive

Note 4

26

2.6

60

6

µs

t

PDI

Presence Detect to INTR

Note 1

0

100

ns

t

PDL

Presence Detect Low Normal

Presence Detect Low Overdrive

Note 4

104

10.4

240

24

µs

t

PDS

Presence Detect Sample, OD=0

Presence Detect Sample, OD=1

30

t (Note 2)

3

t

30

3

37.5

3.75

µs

t

RD

RD Strobe Width

Note 1

125

ns

t

RDV

Read Data Valid Normal

Read Data Valid Overdrive

15

2

µs

t

REC

Recovery Time

1

µs

t

REN

Enable Hold Time from RD

Note 1

20

ns

t

RSTH

Reset Time High, OD=0

Reset Time High, OD=1

500

t

50

t

500

50

625

62.5

µs

t

RSTL

Reset Time Low, OD=0

Reset Time Low, OD=1

488

t

61

t

488

61

610

76.25

µs

t

RVD

Delay from RD to Data

Note 1

60

ns

t

SLOT

Time Slot, OD=0

Time Slot, OD=1

73

t

11

t

73

11

91.25

13.75

µs

t

Timebase Period

1

1.25

µs

t

WEN

Enable Hold Time from WR

Note 1

20

ns

t

WR

WR Strobe Width

Note 1

100

ns

t

WRST

WR High to Reset

Note 1

0

100

ns

NOTES:

1) These values will depend upon the process used to realize the circuit. Values shown are for example

purposes only.

2) The 1-Wire Master will wait for a falling edge on the DQ line to be detected after a reset, for up to 60

4)

Timing determined by 1-wire slave

REFERENCES:

[1] Book of iButton Standards, Dallas Semiconductor, online at

http://www.ibutton.com/ibuttons/standard.pdf