DS1972: 1024-Bit EEPROM iButton

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ABSOLUTE MAXIMUM RATINGS

I/O Voltage to GND

-0.5V, +6V

I/O Sink Current

20mA

Operating Temperature Range

-40°C to +85°C

Junction Temperature

+150°C

Storage Temperature Range

-40°C to +85°C

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only,

and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is

not implied. Exposure to the absolute maximum rating conditions for extended periods may affect device reliability.

ELECTRICAL CHARACTERISTICS

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

I/O PIN GENERAL DATA

1-Wire Pullup Voltage

(Notes 2)

2.8

5.25

V

1-Wire Pullup Resistance

(Notes 2, 3)

0.3

2.2

k

W

Input Capacitance

(Notes 4, 5)

1000

pF

Input Load Current

0.05

6.7

µA

High-to-Low Switching

Threshold

(Notes 5, 6, 7)

0.46

4.4

V

Input Low Voltage

(Notes 2, 8)

0.3

V

Low-to-High Switching

Threshold

(Notes 5, 6, 9)

1.0

4.9

V

Switching Hysteresis

(Notes 5, 6, 10)

0.21

1.70

V

Output Low Voltage

At 4mA (Note 11)

0.4

V

W

5

W

2

Recovery Time

(Notes 2,12)

Overdrive speed, directly prior to Reset

W

5

µs

Standard speed

0.5

5.0

Rising-Edge Hold-off Time

(Notes 5, 13)

Overdrive speed

Not applicable (0)

µs

Standard speed

65

Timeslot Duration

(Note 2, 14)

Overdrive speed

8

µs

I/O PIN, 1-WIRE RESET, PRESENCE DETECT CYCLE

Standard speed

480

640

Reset Low Time (Note 2)

Overdrive speed

48

80

µs

Standard speed

15

60

Presence Detect High

Time

Overdrive speed

2

6

µs

Standard speed

60

240

Presence Detect Low

Time

Overdrive speed

8

24

µs

Standard speed

60

75

Presence Detect Sample

Time (Notes 2, 15)

Overdrive speed

6

10

µs

I/O PIN, 1-Wire WRITE

Standard speed

60

120

5

15.5

Write-0 Low Time (Notes

2, 16)

Overdrive speed

6

15.5

µs

Standard speed

1

15 -

e

Write-1 Low Time

(Notes 2, 17)

Overdrive speed

1

2 -

e

µs

I/O PIN, 1-Wire READ

Standard speed

5

15 -

d

Read Low Time

(Notes 2, 18)

Overdrive speed

1

2 -

d

µs

Standard speed

d

15

Read Sample Time

(Notes 2, 18)

Overdrive speed

d

2

µs