DS2401P Datasheet DS2401P, DS2401X1, DS2401Z | P7-P9

DS2401

7 of 11

INITIALIZATION PROCEDURE “RESET AND PRESENCE PULSES” Figure 5

480µs ≤ t

RSTL

< ∞ *

480µs ≤ t

RSTH

< ∞ (includes recovery time)

15µs ≤ t

PDH

< 60µs

60µs ≤ t

PDL

< 240µs

∗ In order not to mask interrupt signaling by other devices on the 1-Wire bus, t

RSTL

+ t

R

should always

be less than 960µs.

READ/WRITE TIMING DIAGRAM Figure 6

Write-One Time Slot

60µs ≤ t

SLOT

< 120µs

1µs ≤ t

LOW1

< 15µs

1µs ≤ t

REC

< ∞

RESISTOR

MASTER

RESISTOR

MASTER

DS2401

8 of 11

READ/WRITE TIMING DIAGRAM (cont’d) Figure 6

Write-zero Time Slot

60µs ≤ t

LOW0

< t

SLOT

< 120µs

1µs ≤ t

REC

< ∞

Read-data Time Slot

60µs ≤ t

SLOT

< 120µs

1µs ≤ t

LOWR

< 15µs

0 ≤ t

RELEASE

< 45µs

1µs ≤ t

REC

< ∞

t

RDV

= 15µs

t

SU

< 1µs

CRC GENERATION

To validate the data transmitted from the DS2401, the bus master may generate a CRC value from the

data as it is received. This generated value is compared to the value stored in the last 8 bits of the

DS2401. If the two CRC values match, the transmission is error-free.

The equivalent polynomial function of this CRC is: CRC = x

8

+ x

5

+ x

4

+ 1. Additional information about

the Maxim 1-Wire CRC is available in Application Note 27.

CUSTOM DS2401

Customization of a portion of the unique 48-bit serial number by the customer is available. Maxim will

register and assign a specific customer ID in the 12 most significant bits of the 48-bit field. The next most

significant bits are selectable by the customer as a starting value, and the least significant bits are non-

selectable and will be automatically incremented by one. Certain quantities and conditions apply for these

custom parts. Contact your Maxim sales representative for more information.

RESISTOR

MASTER

DS2401

9 of 11

ABSOLUTE MAXIMUM RATINGS

Voltage Range on Any Pin Relative to Ground -0.5V to +7.0V

Operating Temperature Range -40°C to +85°C

Storage Temperature Range -55°C to +125°C

Lead Temperature (TO-92, TSOC, SOT-223 only; soldering, 10s) +300°C

Soldering Temperature (reflow)

TO-92 +250°C

TSOC, SOT-223, WLP +260°C

Flip Chip +240°C

This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this

specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability.

DC ELECTRICAL CHARACTERISTICS

(T

A

= -40°C to +85°C, unless otherwise noted.)

PARAMETER

SYMBOL

MIN

TYP

MAX

UNITS

NOTES

Pullup Voltage

V

PUP

2.8

6.0

V

2

Logic 1

V

IH

2.2

V

1, 6

Logic 0

V

IL

-0.3

+0.3

V

1

Output Logic-Low at 4mA

V

OL

0.4

V

1

Input Load Current

I

L

5

µA

3

Operating Charge

Q

OP

30

nC

7, 8

CAPACITANCE

(T

A

= +25°C, unless otherwise noted.)

PARAMETER

SYMBOL

MIN

TYP

MAX

UNITS

NOTES

I/O (1-Wire)

C

IN/OUT

800

pF

9

AC ELECTRICAL CHARACTERISTICS

(T

A

= -40°C to +85°C, unless otherwise noted.)

PARAMETER

SYMBOL

MIN

TYP

MAX

UNITS

NOTES

Time Slot

t

SLOT

60

120

µs

Write 1 Low Time

t

LOW1

1

15

µs

12

Write 0 Low Time

t

LOW0

60

120

µs

Read Data Valid

t

RDV

15

µs

11

Release Time

t

RELEASE

0

15

45

µs

Read Data Setup

t

SU

1

µs

5

Recovery Time

t

REC

1

µs

Reset Time High

t

RSTH

480

µs

4

Reset Time Low

t

RSTL

480

960

µs

10

Presence Detect High

t

PDH

15

60

µs

Presence Detect Low

t

PDL

60

240

µs

DS2401P

DS2401P

Products related to this Datasheet