DS28EC20P+ Datasheet DS28EC20P+T, DS28EC20+, DS28EC20+T | P1-P3

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GENERAL DESCRIPTION

The DS28EC20 is a 20480-bit, 1-Wire

EEPROM

organized as 80 memory pages of 256 bits each. An

additional page is set aside for control functions.

Data is written to a 32-byte scratchpad, verified, and

then copied to the EEPROM memory. As a special

feature, blocks of eight memory pages can be write

protected or put in EPROM-Emulation mode, where

bits can only be changed from a 1 to a 0 state. The

DS28EC20 communicates over the single-conductor

1-Wire bus. The communication follows the standard

1-Wire protocol. Each device has its own unalterable

and unique 64-bit ROM registration number. The

registration number is used to address the device in

a multidrop 1-Wire net environment.

APPLICATIONS

Device Authentication

IEEE 1451.4 Sensor TEDS

Ink/Toner Cartridges

Medical Sensors

PCB Identification

Wireless Base Stations

ORDERING INFORMATION

PART

TEMP RANGE

PIN-PACKAGE

DS28EC20+

-40°C to +85°C

3 TO-92

DS28EC20+T

-40°C to +85

3 TO-92, T&R

DS28EC20P+

-40°C to +85

6 TSOC

DS28EC20P+T

-40°C to +85

6 TSOC, T&R

+Denotes a lead(Pb)-free/RoHS-compliant package.

T = Tape and reel.

TYPICAL OPERATING CIRCUIT

PX.Y

µC

I/O

DS28EC20

GND

PUP

(300Ω

to 2.2kΩ)

FEATURES

 20480 Bits of Nonvolatile (NV) EEPROM

Partitioned into Eighty 256-Bit Pages

 Individual 8-Page Groups of Memory Pages

(Blocks) can be Permanently Write Protected or

Put in OTP EPROM-Emulation Mode ("Write to

0")

 Read and Write Access Highly Backward-

Compatible to Legacy Devices (e.g., DS2433)

 256-Bit Scratchpad with Strict Read/Write

Protocols Ensures Integrity of Data Transfer

 200k Write/Erase Cycle Endurance at +25°C

 Unique Factory-Programmed 64-Bit Registration

Number Ensures Error-Free Device Selection

and Absolute Part Identity

 Switchpoint Hysteresis and Filtering to Optimize

Performance in the Presence of Noise

 Communicates to Host at 15.4kbps or 90kbps

Using 1-Wire Protocol

 Low-Cost TO-92 Package

 Operating Range: 5V ±5%, -40°C to +85°C

 Operating Range: 3.3V ±5%, 0°C to +70°C

(Standard Speed only)

 IEC 1000-4-2 Level 4 ESD Protection (±8kV

Contact, ±15kV Air, Typical) for I/O Pin

PIN CONFIGURATION

PIN 1 ----------

GND

PIN 2 ---------- I/O

PIN 3 ---------- N.C.

DALLAS

28EC20

BOTTOM VIEW

1 2 3

FOR TAPE-AND-

REEL THE LEADS

ARE FORMED TO

100 MILS (2.54mm)

SPACING VERSUS

50 MILS (1.27mm)

FOR BULK.

TSOC, Top View

PIN 1 ---------- N.C.

PIN 2 ---------- I/O

PIN 3 ---------- GND

PIN 4, 5, 6 ---- N.C.

TO-92

Commands, bytes, and modes are capitalized for clarity.

1-Wire is a registered trademark of Maxim Integrated Products, Inc.

DS28EC20

20Kb 1-

Wire EEPROM

19-6067; Rev 4; 3/12

DS28EC20: 20Kb 1-Wire EEPROM

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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

-55°C to +125°C

Lead Temperature (soldering, 10s)

+300°C

Soldering Temperature (reflow)

TO-92

+250°C

TSOC

+260°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.

5.0V SUPPLY ELECTRICAL CHARACTERISTICS

PUP

= 5.0V ±5%, T

= -40°C to +85°C, unless otherwise noted.) (Note 1)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

I/O PIN GENERAL DATA

1-Wire Pullup Resistance

PUP

(Notes 2, 3)

0.3

2.2

Ω

Input Capacitance

(Notes 4, 5)

2000

Input Load Current

I/O pin at V

PUP

0.05

3.5

µA

High-to-Low Switching

Threshold

(Notes 5, 6, 7) 1.6

PUP

1.8

Input Low Voltage

(Notes 2, 8)

0.5

Low-to-High Switching

Threshold

(Notes 5, 6, 9) 2.5

PUP

1.1

Switching Hysteresis

(Notes 5, 6, 10)

0.30

1.30

Output Low Voltage

At 4mA (Note 11)

0.20

Recovery Time

(Notes 2, 12)

REC

Standard speed

µs

Overdrive speed

Rising-Edge Hold-off Time

(Notes 5, 13)

REH

Standard speed

0.5

5.0

µs

Overdrive speed

Not applicable (0)

Timeslot Duration

(Notes 2, 14)

SLOT

Standard speed

µs

Overdrive speed

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

Reset-Low Time (Note 2) t

RSTL

Standard speed

480

640

µs

Overdrive speed

Presence-Detect High

Time

PDH

Standard speed

µs

Overdrive speed

Presence-Detect Low

Time

PDL

Standard speed

240

µs

Overdrive speed

Presence-Detect Sample

Time (Notes 2, 15)

MSP

Standard speed

µs

Overdrive speed

I/O PIN, 1-Wire WRITE

Write-0 Low Time

(Notes 2, 16, 17)

W0L

Standard speed

120

µs

Overdrive speed

15.5

Write-1 Low Time

(Notes 2, 17)

W1L

Standard speed

µs

Overdrive speed

I/O PIN, 1-Wire READ

Read-Low Time

(Notes 2, 18)

Standard speed

15 - δ

µs

Overdrive speed

2 -

Read-Sample Time

(Notes 2, 18)

MSR

Standard speed

+ δ

µs

Overdrive speed

DS28EC20: 20Kb 1-Wire EEPROM

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PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

EEPROM

Programming Current

PROG

(Note 19)

0.9

Programming Time

PROG

(Note 20)

Write/Erase Cycles

(Endurance) (Notes 21,

22)

At +25°C

200k



At +85°C (worst case) 50k

Data Retention

(Notes 23, 24, 25)

At +85°C (worst case) 40

years

Note 1:

Limits are 100% production tested at T

= +25°C and/or T

= +85°C. Limits over the operating temperature range and relevant

supply voltage range are guaranteed by design and characterization. Typical values are not guaranteed.

Note 2:

System requirement.

Note 3:

Maximum allowable pullup resistance is a function of the number of 1-Wire devices in the system, 1-Wire recovery times, and

current requirements during EEPROM programming. The specified value here applies to systems with only one device and with

the minimum 1-Wire recovery times. For more heavily loaded systems, an active pullup such as that found in the DS2482-x00,

DS2480B, or DS2490 may be required.

Note 4:

Typical value represents the internal parasite capacitance when V

PUP

is first applied. Once the parasite capacitance is charged, it

does not affect normal communication.

Note 5:

Guaranteed by design, characterization and/or simulation only. Not production tested.

Note 6:

, V

, and V

are a function of the internal supply voltage which is itself a function of V

PUP

, R

PUP

, 1-Wire timing, and

capacitive loading on I/O. Lower V

PUP

, higher R

PUP

, shorter t

REC

, and heavier capacitive loading all lead to lower values of V

, V

and V

Note 7:

Voltage below which, during a falling edge on I/O, a logic 0 is detected.

Note 8:

The voltage on I/O needs to be less or equal to V

ILMAX

at all times the master is driving I/O to a logic 0 level.

Note 9:

Voltage above which, during a rising edge on I/O, a logic 1 is detected.

Note 10:

After V

is crossed during a rising edge on I/O, the voltage on I/O has to drop by at least V

to be detected as logic 0.

Note 11:

The I-V characteristic is approximately linear for voltages less than 1V.

Note 12:

Applies to a single device attached to a 1-Wire line.

Note 13:

The earliest recognition of a negative edge is possible at t

REH

after V

has been reached on the preceding rising edge.

Note 14:

Defines maximum possible bit rate. Equal to 1/(t

W0LMIN

+ t

RECMIN

Note 15:

Interval after t

RSTL

during which a bus master can read a logic 0 on I/O if there is a DS28EC20 present. The power-up presence

detect pulse could be outside this interval but will be complete within 2ms after power-up.

Note 16:

Highlighted numbers are NOT in compliance with legacy 1-Wire product standards. See comparison table below.

Note 17:

ε in Figure 11 represents the time required for the pullup circuitry to pull the voltage on I/O up from V

to V

. The actual

maximum duration for the master to pull the line low is t

W1LMAX

+ t

- ε and t

W0LMAX

+ t

- ε, respectively.

Note 18:

δ in Figure 11 represents the time required for the pullup circuitry to pull the voltage on I/O up from V

to the input high threshold

of the bus master. The actual maximum duration for the master to pull the line low is t

RLMAX

+ t

Note 19:

Current drawn from I/O during the EEPROM programming interval. During a programming cycle the voltage at I/O drops by I

PROG

× R

PUP

below V

PUP

. If V

PUP

and R

PUP

are within their EC table limits, the residual I/O voltage meets the guaranteed-by-design

minimum voltage requirements for programming.

Note 20:

The t

PROG

interval begins t

RE HMAX

after the trailing rising edge on I/O for the last time slot of the E/S byte for a valid copy scratchpad

sequence. Interval ends once the device's self-timed EEPROM programming cycle is complete and the current drawn by the

device has returned from I

PROG

to I

Note 21:

Write-cycle endurance is degraded as T

increases.

Note 22:

Not 100% production-tested; guaranteed by reliability monitor sampling.

Note 23:

Data retention is degraded as T

increases.

Note 24:

Guaranteed by 100% production test at elevated temperature for a shorter time; equivalence of this production test to data sheet

limit at operating temperature range is established by reliability testing.

Note 25:

EEPROM writes may become nonfunctional after the data retention time is exceeded. Long-time storage at elevated

temperatures is not recommended; the device may lose its write capability after 10 years at +125°C or 40 years at +85°C.

LEGACY VALUES

DS28EC20 VALUES

PARAMETER

STANDARD SPEED

OVERDRIVE SPEED#

STANDARD SPEED

OVERDRIVE SPEED#

MIN

MAX

MIN

MAX

MIN

MAX

MIN

MAX

SLOT

(incl. t

REC

)

61µs

(undefined)

7µs

(undefined)

65µs*

(undefined)

11µs

(undefined)

RSTL

480µs

(undefined)

48µs

80µs

480µs

640µs

48µs

80µs

PDH

15µs

60µs

2µs

6µs

15µs

60µs

2µs

6µs

PDL

60µs

240µs

8µs

24µs

60µs

240µs

8µs

24µs

W0L

60µs

120µs

6µs

16µs

60µs

120µs

6µs

15.5µs

*Intentional change, longer recovery time requirement due to modified 1-Wire front-end.

#For operation at overdrive speed, the DS28EC20 requires V

PUP

to be 5V ±5%.

P1-P3 P4-P6 P7-P9 P10-P12 P13-P15 P16-P18 P19-P21 P22-P24 P25-P27

DS28EC20P+

Mfr. #:

Buy DS28EC20P+

Manufacturer:

Maxim Integrated

Description:

EEPROM 20Kb 1-Wire EEPROM

Lifecycle:

New from this manufacturer.

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DS28EC20P+

DS28EC20P+

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