AT24C64D-MAHM-E - MICROCHIP TECHNOLOGY

AT24C64D

I²C-Compatible (Two-Wire) Serial EEPROM 64-Kbit

(8,192 x 8)

Features

• Low-Voltage Operation:

– VCC = 1.7V to 5.5V

• Internally Organized as 8,192 x 8 (64K)

• Industrial Temperature Range: -40°C to +85°C

• I2C-Compatible (Two-Wire) Serial Interface:

– 100 kHz Standard mode, 1.7V to 5.5V

– 400 kHz Fast mode, 1.7V to 5.5V

– 1 MHz Fast Mode Plus (FM+), 2.5V to 5.5V

• Schmitt Triggers, Filtered Inputs for Noise Suppression

• Bidirectional Data Transfer Protocol

• Write-Protect Pin for Full Array Hardware Data Protection

• Ultra Low Active Current (3 mA maximum) and Standby Current (6 µA maximum)

• 32-byte Page Write Mode:

– Partial page writes allowed

• Random and Sequential Read Modes

• Self-Timed Write Cycle within 5 ms Maximum

• ESD Protection > 4,000V

• High Reliability:

– Endurance: 1,000,000 write cycles

– Data retention: 100 years

• Green Package Options (Lead-free/Halide-free/RoHS compliant)

• Die Sale Options: Wafer Form and Bumped Wafers

Packages

• 8-lead SOIC, 8-lead TSSOP, 8-pad UDFN, 8-ball VFBGA, 8-pad XDFN and 4‑ball/6‑ball WLCSP

Table of Contents

Features.......................................................................................................................... 1

Packages.........................................................................................................................1

1. Package Types (not to scale).................................................................................... 4

2. Pin Descriptions.........................................................................................................5

2.1. Device Address Inputs (A0, A1, A2).............................................................................................5

2.2. Ground......................................................................................................................................... 5

2.3. Serial Data (SDA).........................................................................................................................5

2.4. Serial Clock (SCL)........................................................................................................................6

2.5. Write-Protect (WP)....................................................................................................................... 6

2.6. Device Power Supply................................................................................................................... 6

3. Description.................................................................................................................7

3.1. System Configuration Using Two-Wire Serial EEPROMs ........................................................... 7

3.2. Block Diagram.............................................................................................................................. 8

4. Electrical Characteristics........................................................................................... 9

4.1. Absolute Maximum Ratings..........................................................................................................9

4.2. DC and AC Operating Range.......................................................................................................9

4.3. DC Characteristics....................................................................................................................... 9

4.4. AC Characteristics......................................................................................................................10

4.5. Electrical Specifications..............................................................................................................11

5. Device Operation and Communication....................................................................13

5.1. Clock and Data Transition Requirements...................................................................................13

5.2. Start and Stop Conditions.......................................................................................................... 13

5.3. Acknowledge and No-Acknowledge...........................................................................................14

5.4. Standby Mode............................................................................................................................ 14

5.5. Software Reset...........................................................................................................................15

6. Memory Organization.............................................................................................. 16

6.1. Device Addressing..................................................................................................................... 16

7. Write Operations......................................................................................................18

7.1. Byte Write...................................................................................................................................18

7.2. Page Write..................................................................................................................................18

7.3. Acknowledge Polling.................................................................................................................. 19

7.4. Write Cycle Timing..................................................................................................................... 20

7.5. Write Protection..........................................................................................................................20

8. Read Operations..................................................................................................... 21

8.1. Current Address Read................................................................................................................21

8.2. Random Read............................................................................................................................ 21

AT24C64D

8.3. Sequential Read.........................................................................................................................22

9. Device Default Condition from Microchip................................................................ 23

10. Packaging Information.............................................................................................24

10.1. Package Marking Information.....................................................................................................24

11. Revision History.......................................................................................................37

The Microchip Web Site................................................................................................ 38

Customer Change Notification Service..........................................................................38

Customer Support......................................................................................................... 38

Product Identification System........................................................................................39

Microchip Devices Code Protection Feature................................................................. 40

Legal Notice...................................................................................................................40

Trademarks................................................................................................................... 40

Quality Management System Certified by DNV.............................................................41

Worldwide Sales and Service........................................................................................42

AT24C64D

1. Package Types (not to scale)

8-Lead SOIC/TSSOP

(Top View)

A0 1

GND

VCC

SCL

SDA

GND

VCC

SCL

SDA

8-Ball VFBGA

(Top View)

SDA

6-Ball WLCSP(1)

(Top View)

SCL

VCC

GND WP

GND

VCC

SCL

SDA

8-Pad UDFN/XDFN

(Top View)

VCC

SCL

4-Ball WLCSP(1)

(Top View)

GND

SDA

A2A1

B1 B2

Note:

1. For use of the 4‑ball and 6‑ball WLCSP packages, refer to Device Addressing for details about

setting the A2, A1 and A0 hardware address bits.

AT24C64D

Package Types (not to scale)

2. Pin Descriptions

The descriptions of the pins are listed in Table 2-1.

Table 2-1. Pin Function Table

Name 8‑Lead

SOIC

8‑Lead

TSSOP

8‑Pad

UDFN(1)

8‑Pad

XDFN

8‑Ball

VFBGA

4‑Ball

WLCSP(2)

6‑Ball

WLCSP(2)

Function

A0(3)1 1 1 1 1 －－ Device Address

Input

A1(3)2 2 2 2 2 －－ Device Address

Input

A2(3)3 3 3 3 3 －B3 Device Address

Input

GND 4 4 4 4 4 A2 B2 Ground

SDA 5 5 5 5 5 B2 B1 Serial Data

SCL 6 6 6 6 6 B1 A1 Serial Clock

WP(3)7 7 7 7 7 －A2 Write-Protect

VCC 8 8 8 8 8 A1 A3 Device Power

Supply

Note:

1. The exposed pad on this package can be connected to GND or left floating.

2. For use of the 4‑ball and 6‑ball WLCSP packages, refer to Device Addressing for details about

setting the A2, A1 and A0 hardware address bits.

3. If the A0, A1, A2 and WP pins are not driven, they are internally pulled down to GND. In order to

operate in a wide variety of application environments, the pull‑down mechanism is intentionally

designed to be somewhat strong. Once these pins are biased above the CMOS input buffer’s trip

point (~0.5 x VCC), the pull‑down mechanism disengages. Microchip recommends connecting these

pins to a known state whenever possible.

2.1 Device Address Inputs (A0, A1, A2)

The A0, A1 and A2 pins are device address inputs that are hard-wired (directly to GND or to VCC) for

compatibility with other two-wire Serial EEPROM devices. When the pins are hard-wired, as many as

eight devices may be addressed on a single bus system. A device is selected when a corresponding

hardware and software match is true. If these pins are left floating, the A0, A1 and A2 pins will be

internally pulled down to GND. However, due to capacitive coupling that may appear in customer

applications, Microchip recommends always connecting the address pins to a known state. When using a

pull‑up resistor, Microchip recommends using 10 kΩ or less.

2.2 Ground

The ground reference for the power supply. GND should be connected to the system ground.

2.3 Serial Data (SDA)

The SDA pin is an open-drain bidirectional input/output pin used to serially transfer data to and from the

device. The SDA pin must be pulled high using an external pull-up resistor (not to exceed 10 kΩ in value)

and may be wire-ORed with any number of other open-drain or open-collector pins from other devices on

the same bus.

AT24C64D

Pin Descriptions

2.4 Serial Clock (SCL)

The SCL pin is used to provide a clock to the device and to control the flow of data to and from the

device. Command and input data present on the SDA pin is always latched in on the rising edge of SCL,

while output data on the SDA pin is clocked out on the falling edge of SCL. The SCL pin must either be

forced high when the serial bus is idle or pulled high using an external pull-up resistor.

2.5 Write-Protect (WP)

The write-protect input, when connected to GND, allows normal write operations. When the WP pin is

connected directly to VCC, all write operations to the protected memory are inhibited.

If the pin is left floating, the WP pin will be internally pulled down to GND. However, due to capacitive

coupling that may appear in customer applications, Microchip recommends always connecting the WP

pin to a known state. When using a pull‑up resistor, Microchip recommends using 10 kΩ or less.

Table 2-2. Write-Protect

WP Pin Status Part of the Array Protected

At VCC Full Array

At GND Normal Write Operations

2.6 Device Power Supply

The VCC pin is used to supply the source voltage to the device. Operations at invalid VCC voltages may

produce spurious results and should not be attempted.

AT24C64D

Pin Descriptions

3. Description

The AT24C64D provides 65,536 bits of Serial Electrically Erasable and Programmable Read-Only

Memory (EEPROM) organized as 8,192 words of 8 bits each. The device’s cascading feature allows up to

eight devices to share a common two‑wire bus. The device is optimized for use in many industrial and

commercial applications where low‑power and low‑voltage operation are essential. The devices are

available in space‑saving 8‑lead SOIC, 8‑lead TSSOP, 8‑pad UDFN, 8‑pad XDFN, 8‑ball VFBGA and

4‑ball/6‑ball WLCSP packages. All packages operate from 1.7V to 5.5V.

3.1 System Configuration Using Two-Wire Serial EEPROMs

I2C Bus Master:

Microcontroller

Slave 0

AT24CXXX

VCC

SDA

SCL

GND

VCC

GND

SCL

SDA

RPUP(max) = tR(max)

0.8473 x CL

RPUP(min) = VCC - VOL(max)

IOL

Slave 1

AT24CXXX

VCC

SDA

SCL

GND

Slave 7

AT24CXXX

VCC

SDA

SCL

GND

VCC

AT24C64D

Description

3.2 Block Diagram

AT24C64D

Description

4. Electrical Characteristics

4.1 Absolute Maximum Ratings

Temperature under bias -55°C to +125°C

Storage temperature -65°C to +150°C

VCC 6.25V

Voltage on any pin with respect to ground -1.0V to +7.0V

DC output current 5.0 mA

ESD protection >4 kV

Note: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to

the device. This is a stress rating only and functional operation of the device at these or any other

conditions above those indicated in the operation listings of this specification is not implied. Exposure to

absolute maximum rating conditions for extended periods may affect device reliability.

4.2 DC and AC Operating Range

Table 4-1. DC and AC Operating Range

AT24C64D

Operating Temperature (Case) Industrial Temperature Range -40°C to +85°C

VCC Power Supply Low Voltage Grade 1.7V to 5.5V

4.3 DC Characteristics

Table 4-2. DC Characteristics

Parameter Symbol Minimum Typical(1)Maximum Units Test Conditions

Supply Voltage VCC1 1.7 — 5.5 V

Supply Current ICC1 — 0.4 1.0 mA VCC = 5.0V, Read at 400 kHz

Supply Current ICC2 — 2.0 3.0 mA VCC = 5.0V, Write at 400 kHz

Standby Current ISB1 — — 1.0 μA VCC = 1.7V, VIN = VCC or GND

— — 6.0 μA VCC = 5.0V, VIN = VCC or GND

Input Leakage

Current

ILI — 0.10 3.0 μA VIN = VCC or GND; VCC = 5.0V

Output Leakage

Current

ILO — 0.05 3.0 μA VOUT = VCC or GND;

VCC = 5.0V

Input Low Level VIL -0.6 — VCC x 0.3 V Note 2

Input High Level VIH VCC x 0.7 — VCC + 0.5 V Note 2

AT24C64D

Electrical Characteristics

...........continued

Parameter Symbol Minimum Typical(1)Maximum Units Test Conditions

Output Low Level VOL1 — — 0.2 V VCC = 1.7V, IOL = 0.15 mA

Output Low Level VOL2 — — 0.4 V VCC = 3.0V, IOL = 2.1 mA

Note:

1. Typical values characterized at TA = +25°C unless otherwise noted.

2. This parameter is characterized but is not 100% tested in production.

4.4 AC Characteristics

Table 4-3. AC Characteristics(1)

Parameter Symbol Fast Mode Fast Mode Plus Units

Vcc = 1.7V to 2.5V Vcc = 2.5V to 5.0V

Min. Max. Min. Max.

Clock Frequency, SCL fSCL — 400 — 1000 kHz

Clock Pulse Width Low tLOW 1300 — 500 — ns

Clock Pulse Width High tHIGH 600 — 400 — ns

Noise Suppression Time(2)tI— 100 — 50 ns

Clock Low to Data Out Valid tAA 50 900 50 450 ns

Bus Free Time between Stop and

Start(2)

tBUF 1300 — 500 — ns

Start Hold Time tHD.STA 600 — 250 — ns

Start Set‑up Time tSU.STA 600 — 250 — ns

Data In Hold Time tHD.DAT 0 — 0 — ns

Data In Set‑up Time tSU.DAT 100 — 100 — ns

Inputs Rise Time(2)tR— 300 — 300 ns

Inputs Fall Time(2)tF— 300 — 100 ns

Stop Set-up Time tSU.STO 600 — 250 — ns

Data Out Hold Time tDH 50 — 50 — ns

Write Cycle Time tWR — 5 — 5 ms

Note:

1. AC measurement conditions:

– RPUP (SDA bus line pull-up resistor to VCC): 1.3 kΩ (1000 kHz), 4 kΩ (400 kHz), 10 kΩ

(100 kHz)

– Input pulse voltages: 0.3 VCC to 0.7 VCC

– Input rise and fall times: ≤ 50 ns

AT24C64D

Electrical Characteristics

– Input and output timing reference voltages: 0.5 x VCC

2. This parameter is ensured by characterization and is not 100% tested.

Figure 4-1. Bus Timing

SCL

SDA In

SDA Out

tHIGH

tLOW

tDH

tAA tBUF

tSU.STO

tSU.DAT

tHD.DAT

tHD.STA

tSU.STA

4.5 Electrical Specifications

4.5.1 Power-Up Requirements and Reset Behavior

During a power-up sequence, the VCC supplied to the AT24C64D should monotonically rise from GND to

the minimum VCC level, as specified in Table 4-1, with a slew rate no faster than 0.1 V/µs.

4.5.1.1 Device Reset

To prevent inadvertent write operations or any other spurious events from occurring during a power-up

sequence, the AT24C64D includes a Power-on Reset (POR) circuit. Upon power-up, the device will not

respond to any commands until the VCC level crosses the internal voltage threshold (VPOR) that brings the

device out of Reset and into Standby mode.

The system designer must ensure the instructions are not sent to the device until the VCC supply has

reached a stable value greater than or equal to the minimum VCC level. Additionally, once the VCC is

greater than or equal to the minimum VCC level, the bus master must wait at least tPUP before sending the

first command to the device. See Table 4-4 for the values associated with these power-up parameters.

Table 4-4. Power-up Conditions(1)

Symbol Parameter Min. Max. Units

tPUP Time required after VCC is stable before the device can accept commands 100 －µs

VPOR Power-on Reset Threshold Voltage －1.5 V

tPOFF Minimum time at VCC = 0V between power cycles 500 －ms

Note:

1. These parameters are characterized but they are not 100% tested in production.

If an event occurs in the system where the VCC level supplied to the AT24C64D drops below the

maximum VPOR level specified, it is recommended that a full power cycle sequence be performed by first

driving the VCC pin to GND, waiting at least the minimum tPOFF time and then performing a new power-up

sequence in compliance with the requirements defined in this section.

AT24C64D

Electrical Characteristics

4.5.2 Pin Capacitance

Table 4-5. Pin Capacitance(1)

Symbol Test Condition Max. Units Conditions

CI/O Input/Output Capacitance (SDA) 8 pF VI/O = 0V

CIN Input Capacitance (A0, A1, A2 and SCL) 6 pF VIN = 0V

Note:

1. This parameter is characterized but is not 100% tested in production.

4.5.3 EEPROM Cell Performance Characteristics

Table 4-6. EEPROM Cell Performance Characteristics

Operation Test Condition Min. Max. Units

Write Endurance(1)TA = 25°C, VCC = 3.3V,

Page Write mode

1,000,000 — Write Cycles

Data Retention(1)TA = 55°C 100 — Years

Note:

1. Performance is determined through characterization and the qualification process.

AT24C64D

Electrical Characteristics

5. Device Operation and Communication

The AT24C64D operates as a slave device and utilizes a simple I2C-compatible two-wire digital serial

interface to communicate with a host controller, commonly referred to as the bus master. The master

initiates and controls all read and write operations to the slave devices on the serial bus, and both the

master and the slave devices can transmit and receive data on the bus.

The serial interface is comprised of just two signal lines: Serial Clock (SCL) and Serial Data (SDA).

The SCL pin is used to receive the clock signal from the master, while the bidirectional SDA pin is used to

receive command and data information from the master as well as to send data back to the master.

Data is always latched into the AT24C64D on the rising edge of SCL and always output from the device

on the falling edge of SCL. Both the SCL and SDA pin incorporate integrated spike suppression filters

and Schmitt Triggers to minimize the effects of input spikes and bus noise.

All command and data information is transferred with the Most Significant bit (MSb) first. During bus

communication, one data bit is transmitted every clock cycle, and after eight bits (one byte) of data have

been transferred, the receiving device must respond with either an Acknowledge (ACK) or a

No-Acknowledge (NACK) response bit during a ninth clock cycle (ACK/NACK clock cycle) generated by

the master. Therefore, nine clock cycles are required for every one byte of data transferred. There are no

unused clock cycles during any read or write operation, so there must not be any interruptions or breaks

in the data stream during each data byte transfer and ACK or NACK clock cycle.

During data transfers, data on the SDA pin must only change while SCL is low, and the data must remain

stable while SCL is high. If data on the SDA pin changes while SCL is high, then either a Start or a Stop

condition will occur. Start and Stop conditions are used to initiate and end all serial bus communication

between the master and the slave devices. The number of data bytes transferred between a Start and a

Stop condition is not limited and is determined by the master. In order for the serial bus to be idle, both

the SCL and SDA pins must be in the logic-high state at the same time.

5.1 Clock and Data Transition Requirements

The SDA pin is an open-drain terminal and therefore must be pulled high with an external pull‑up resistor.

SCL is an input pin that can either be driven high or pulled high using an external pull‑up resistor. Data on

the SDA pin may change only during SCL low time periods. Data changes during SCL high periods will

indicate a Start or Stop condition as defined below. The relationship of the AC timing parameters with

respect to SCL and SDA for the AT24C64D are shown in the timing waveform in Figure 4-1. The AC

timing characteristics and specifications are outlined in AC Characteristics.

5.2 Start and Stop Conditions

5.2.1 Start Condition

A Start condition occurs when there is a high-to-low transition on the SDA pin while the SCL pin is at a

stable logic ‘1’ state and will bring the device out of Standby mode. The master uses a Start condition to

initiate any data transfer sequence; therefore, every command must begin with a Start condition.

The device will continuously monitor the SDA and SCL pins for a Start condition but will not respond

unless one is detected. Refer to Figure 5-1 for more details.

5.2.2 Stop Condition

A Stop condition occurs when there is a low-to-high transition on the SDA pin while the SCL pin is stable

in the logic ‘1’ state.

AT24C64D

Device Operation and Communication

The master can use the Stop condition to end a data transfer sequence with the AT24C64D, which will

subsequently return to Standby mode. The master can also utilize a repeated Start condition instead of a

Stop condition to end the current data transfer if the master will perform another operation. Refer to

Figure 5-1 for more details.

5.3 Acknowledge and No-Acknowledge

After every byte of data is received, the receiving device must confirm to the transmitting device that it

has successfully received the data byte by responding with what is known as an Acknowledge (ACK).

An ACK is accomplished by the transmitting device first releasing the SDA line at the falling edge of the

eighth clock cycle followed by the receiving device responding with a logic ‘0’ during the entire high period

of the ninth clock cycle.

When the AT24C64D is transmitting data to the master, the master can indicate that it is done receiving

data and wants to end the operation by sending a logic ‘1’ response to the AT24C64D instead of an ACK

response during the ninth clock cycle. This is known as a No-Acknowledge (NACK) and is accomplished

by the master sending a logic ‘1’ during the ninth clock cycle, at which point the AT24C64D will release

the SDA line so the master can then generate a Stop condition.

The transmitting device, which can be the bus master or the Serial EEPROM, must release the SDA line

at the falling edge of the eighth clock cycle to allow the receiving device to drive the SDA line to a logic ‘0’

to ACK the previous 8-bit word. The receiving device must release the SDA line at the end of the ninth

clock cycle to allow the transmitter to continue sending new data. A timing diagram has been provided in

Figure 5-1 to better illustrate these requirements.

Figure 5-1. Start Condition, Data Transitions, Stop Condition and Acknowledge

SCL

SDA

Must Be

Stable

SDA

Change

Allowed

SDA

Change

Allowed

Acknowledge

Valid

Stop

Condition

Start

Condition

1 2 8 9

SDA

Must Be

Stable Acknowledge Window

The transmitting device (Master or Slave)

must release the SDA line at this point to allow

the receiving device (Master or Slave) to drive the

SDA line low to ACK the previous 8-bit word.

The receiver (Master or Slave)

must release the SDA line at

this point to allow the transmitter

to continue sending new data.

5.4 Standby Mode

The AT24C64D features a low‑power Standby mode that is enabled when any one of the following

occurs:

• A valid power-up sequence is performed (see Power-Up Requirements and Reset Behavior).

• A Stop condition is received by the device unless it initiates an internal write cycle (see Write

Operations).

• At the completion of an internal write cycle (see Write Operations).

AT24C64D

Device Operation and Communication

5.5 Software Reset

After an interruption in protocol, power loss or system Reset, any two‑wire device can be protocol reset

by clocking SCL until SDA is released by the EEPROM and goes high. The number of clock cycles until

SDA is released by the EEPROM will vary. The software Reset sequence should not take more than nine

dummy clock cycles. Once the software Reset sequence is complete, new protocol can be sent to the

device by sending a Start condition followed by the protocol. Refer to Figure 5-2 for an illustration.

Figure 5-2. Software Reset

SCL 9

Device is

8321

SDA

Dummy Clock Cycles

SDA Released

Software Reset

by EEPROM

In the event that the device is still non-responsive or remains active on the SDA bus, a power cycle must

be used to reset the device (see Power-Up Requirements and Reset Behavior).

AT24C64D

Device Operation and Communication

6. Memory Organization

The AT24C64D is internally organized as 256 pages of 32 bytes each.

6.1 Device Addressing

Accessing the device requires an 8‑bit device address byte following a Start condition to enable the

device for a read or write operation. Since multiple slave devices can reside on the serial bus, each slave

device must have its own unique address so the master can access each device independently.

The Most Significant four bits of the device address byte is referred to as the device type identifier. The

device type identifier ‘1010’ (Ah) is required in bits 7 through 4 of the device address byte (see Table

6-1).

Following the 4-bit device type identifier are the hardware slave address bits, A2, A1 and A0. These bits

can be used to expand the address space by allowing up to eight Serial EEPROM devices on the same

bus. These hardware slave address bits must correlate with the voltage level on the corresponding

hardwired device address input pins A0, A1 and A2. The A0, A1 and A2 pins use an internal proprietary

circuit that automatically biases the pin to a logic ‘0’ state if the pin is allowed to float. In order to operate

in a wide variety of application environments, the pull‑down mechanism is intentionally designed to be

somewhat strong. Once the pin is biased above the CMOS input buffer's trip point (~0.5 x VCC), the

pull‑down mechanism disengages. Microchip recommends connecting the A0, A1 and A2 pins to a known

state whenever possible.

When using the 6-ball WLCSP package, the A1 and A0 pins are not accessible and are left floating. The

previously mentioned automatic pull-down circuit will set this pin to a logic ‘0’ state. As a result, to

properly communicate with the device in the 6-ball WLCSP package, the A1 and A0 software bits must

always be set to logic ‘0’ for any operation. Refer to Table 6-1 to review these bit positions.

When using the 4-ball WLCSP package, the A2, A1 and A0 pins are not accessible and are left floating.

The previously mentioned automatic pull-down circuit will set this pin to a logic ‘0’ state. As a result, to

properly communicate with the device in the 4-ball WLCSP package, the A2, A1 and A0 software bits

must always be set to logic ‘0’ for any operation. Refer to Table 6-1 to review these bit positions.

The eighth bit (bit 0) of the device address byte is the Read/Write Select bit. A read operation is initiated if

this bit is high and a write operation is initiated if this bit is low.

Upon the successful comparison of the device address byte, the AT24C64D will return an ACK. If a valid

comparison is not made, the device will NACK.

Table 6-1. Device Addressing

Package Device Type Identifier Hardware Slave

Address Bits

R/W Select

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

SOIC, TSSOP, UDFN,

XDFN, VFBGA

1 0 1 0 A2 A1 A0 R/W

4-ball WLCSP 1010000 R/W

6-ball WLCSP 1 0 1 0 A2 0 0 R/W

AT24C64D

Memory Organization

For all operations except the current address read, two 8‑bit word address bytes must be transmitted to

the device immediately following the device address byte. The word address bytes consist of the 13‑bit

memory array word address, and are used to specify which byte location in the EEPROM to start reading

or writing.

The first word address byte contains the five Most Significant bits of the word address (A12 through A8)

in bit positions four through zero, as seen in Table 6-2. The remainder of the first word address byte are

“don’t care” bits (in bit positions seven through five) as they are outside of the addressable 64‑Kbit range.

Upon completion of the first word address byte, the AT24C64D will return an ACK.

Table 6-2. First Word Address Byte

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

XXXA12 A11 A10 A9 A8

Next, the second word address byte is sent to the device which provides the remaining eight bits of the

word address (A7 through A0). Upon completion of the second word address byte, the AT24C64D will

return an ACK. See Table 6-3 to review these bit positions.

Table 6-3. Second Word Address Byte

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

A7 A6 A5 A4 A3 A2 A1 A0

AT24C64D

Memory Organization

7. Write Operations

All write operations for the AT24C64D begin with the master sending a Start condition, followed by a

device address byte with the R/W bit set to logic ‘0’, and then by the word address bytes. The data

value(s) to be written to the device immediately follow the word address bytes.

7.1 Byte Write

The AT24C64D supports the writing of a single 8-bit byte. Selecting a data word in the AT24C64D

requires 13-bit word address.

Upon receipt of the proper device address and the word address bytes, the EEPROM will send an

Acknowledge. The device will then be ready to receive the 8-bit data word. Following receipt of the 8‑bit

data word, the EEPROM will respond with an ACK. The addressing device, such as a bus master, must

then terminate the write operation with a Stop condition. At that time, the EEPROM will enter an internally

self-timed write cycle, which will be completed within tWR, while the data word is being programmed into

the nonvolatile EEPROM. All inputs are disabled during this write cycle, and the EEPROM will not

respond until the write is complete.

Figure 7-1. Byte Write

SCL

SDA

Start Condition

by Master

Device Address Byte First Word Address Byte

MSB MSB

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

1 0 1 0 A2 A1 A0 0 0

Second Word Address Byte Data Word

Stop Condition

by Master

MSB MSB

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

D7 D6 D5 D4 D3 D2 D1 D0 0

X X X A12 A11 A10 A9 A8 0

ACK

from Slave

ACK

from Slave

ACK

from Slave

ACK

from Slave

A7 A6 A5 A4 A3 A2 A1 A0 0

7.2 Page Write

A page write operation allows up to 32 bytes to be written in the same write cycle, provided all bytes are

in the same row of the memory array (where address bits A12 through A5 are the same). Partial page

writes of less than 32 bytes are also allowed.

A page write is initiated the same way as a byte write, but the bus master does not send a Stop condition

after the first data word is clocked in. Instead, after the EEPROM acknowledges receipt of the first data

word, the bus master can transmit up to thirty one additional data words. The EEPROM will respond with

an ACK after each data word is received. Once all data to be written has been sent to the device, the bus

master must issue a Stop condition (see Figure 7-2) at which time the internally self-timed write cycle will

begin.

The lower five bits of the word address are internally incremented following the receipt of each data word.

The higher order address bits are not incremented and retain the memory page row location. Page write

AT24C64D

Write Operations

operations are limited to writing bytes within a single physical page, regardless of the number of bytes

actually being written. When the incremented word address reaches the page boundary, the address

counter will roll-over to the beginning of the same page. Nevertheless, creating a roll‑over event should

be avoided as previously loaded data in the page could become unintentionally altered.

Figure 7-2. Page Write

SCL

SDA

Start Condition

by Master ACK

from Slave

ACK

from Slave

Device Address Byte First Word Address Byte

MSB MSB

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

1 0 1 0 A2 A1 A0 0 0 X X X A12 A11 A10 A9 A8 0

ACK

from Slave

ACK

from Slave

Stop Condition

by Master

ACK

from Slave

Second Word Address Byte Data Word (n) Data Word (n+x), max of 32 without rollover

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

A7 A6 A5 A4 A3 A2 A1 A0 0 D7 D6 D5 D4 D3 D2 D1 D0 0 D7 D6 D5 D4 D3 D2 D1 D0 0

MSB MSB MSB

7.3 Acknowledge Polling

An Acknowledge Polling routine can be implemented to optimize time-sensitive applications that would

prefer not to wait the fixed maximum write cycle time (tWR). This method allows the application to know

immediately when the Serial EEPROM write cycle has completed, so a subsequent operation can be

started.

Once the internally self-timed write cycle has started, an Acknowledge Polling routine can be initiated.

This involves repeatedly sending a Start condition followed by a valid device address byte with the R/W

bit set at logic ‘0’. The device will not respond with an ACK while the write cycle is ongoing. Once the

internal write cycle has completed, the EEPROM will respond with an ACK, allowing a new read or write

operation to be immediately initiated. A flowchart has been included below in Figure 7-3 to better illustrate

this technique.

Figure 7-3. Acknowledge Polling Flowchart

Did

the device

ACK?

Send any

Write

protocol.

Send

Stop

condition

to initiate the

Write cycle.

Send Start

condition followed

by a valid

Device Address

byte with R/W = 0.

Proceed to

next Read or

Write operation.

YES

AT24C64D

Write Operations

7.4 Write Cycle Timing

The length of the self-timed write cycle (tWR) is defined as the amount of time from the Stop condition that

begins the internal write cycle to the Start condition of the first device address byte sent to the AT24C64D

that it subsequently responds to with an ACK. Figure 7-4 has been included to show this measurement.

During the internally self-timed write cycle, any attempts to read from or write to the memory array will not

be processed.

Figure 7-4. Write Cycle Timing

tWR

Stop

Condition

Start

Condition

Data Word n

ACKD0

SDA

Stop

Condition

SCL 8 9

ACK

First Acknowledge from the device

to a valid device address sequence after

write cycle is initiated. The minimum tWR

can only be determined through

the use of an ACK Polling routine.

7.5 Write Protection

The AT24C64D utilizes a hardware data protection scheme that allows the user to write‑protect the entire

memory contents when the WP pin is at VCC (or a valid VIH). No write protection will be set if the WP pin

is at GND or left floating. The 4‑ball WLCSP version of the device does not include any write protection

features.

Table 7-1. AT24C64D Write-Protect Behavior

WP Pin Voltage Part of the Array Protected

VCC Full Array

GND None － Write Protection Not Enabled

The status of the WP pin is sampled at the Stop condition for every byte write or page write operation

prior to the start of an internally self‑timed write cycle. Changing the WP pin state after the Stop condition

has been sent will not alter or interrupt the execution of the write cycle.

If an attempt is made to write to the device while the WP pin has been asserted, the device will

acknowledge the device address, word address and data bytes, but no write cycle will occur when the

Stop condition is issued. The device will immediately be ready to accept a new read or write command.

AT24C64D

Write Operations

8. Read Operations

Read operations are initiated the same way as write operations with the exception that the Read/Write

Select bit in the device address byte must be a logic ‘1’. There are three read operations:

• Current Address Read

• Random Address Read

• Sequential Read

8.1 Current Address Read

The internal data word address counter maintains the last address accessed during the last read or write

operation, incremented by one. This address stays valid between operations as long as the VCC is

maintained to the part. The address roll-over during a read is from the last byte of the last page to the first

byte of the first page of the memory.

A current address read operation will output data according to the location of the internal data word

address counter. This is initiated with a Start condition, followed by a valid device address byte with the

R/W bit set to logic ‘1’. The device will ACK this sequence and the current address data word is serially

clocked out on the SDA line. All types of read operations will be terminated if the bus master does not

respond with an ACK (it NACKs) during the ninth clock cycle. After the NACK response, the master may

send a Stop condition to complete the protocol, or it can send a Start condition to begin the next

sequence.

Figure 8-1. Current Address Read

SCL

SDA

Device Address Byte Data Word (n)

Start Condition

by Master ACK

from Slave

NACK

from Master

Stop Condition

by Master

MSB MSB

1 0 1 0 A2 A1 A0 1 0 D7 D6 D5 D4 D3 D2 D1 D0 1

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

8.2 Random Read

A random read begins in the same way as a byte write operation does to load in a new data word

address. This is known as a “dummy write” sequence; however, the data byte and the Stop condition of

the byte write must be omitted to prevent the part from entering an internal write cycle. Once the device

address and word address are clocked in and acknowledged by the EEPROM, the bus master must

generate another Start condition. The bus master now initiates a current address read by sending a Start

condition, followed by a valid device address byte with the R/W bit set to logic ‘1’. The EEPROM will ACK

the device address and serially clock out the data word on the SDA line. All types of read operations will

be terminated if the bus master does not respond with an ACK (it NACKs) during the ninth clock cycle.

After the NACK response, the master may send a Stop condition to complete the protocol, or it can send

a Start condition to begin the next sequence.

AT24C64D

Read Operations

Figure 8-2. Random Read

SCL

SDA

Start Condition

by Master

Device Address Byte First Word Address Byte

MSB MSB

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

1 0 1 0 A2 A1 A0 0 0

Dummy Write

Start Condition

by Master

Device Address Byte Data Word (n)

Stop Condition

by Master

MSB MSB

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

1 0 1 0 A2 A1 A0 1 0 D7 D6 D5 D4 D3 D2 D1 D0 1

X X X A12 A11 A10 A9 A8 0

ACK

from Slave

ACK

from Slave

ACK

from Slave

NACK

from Master

Second Word Address Byte

MSB

A7 A6 A5 A4 A3 A2 A1 A0 0

ACK

from Slave

8.3 Sequential Read

Sequential reads are initiated by either a current address read or a random read. After the bus master

receives a data word, it responds with an Acknowledge. As long as the EEPROM receives an ACK, it will

continue to increment the word address and serially clock out sequential data words. When the maximum

memory address is reached, the data word address will roll-over and the sequential read will continue

from the beginning of the memory array. All types of read operations will be terminated if the bus master

does not respond with an ACK (it NACKs) during the ninth clock cycle. After the NACK response, the

master may send a Stop condition to complete the protocol, or it can send a Start condition to begin the

next sequence.

Figure 8-3. Sequential Read

SCL

SDA

Start Condition

by Master ACK

from Slave

ACK

from Master

Device Address Byte Data Word (n)

MSB MSB

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

1 0 1 0 A2 A1 A0 1 0 D7 D6 D5 D4 D3 D2 D1 D0 0

ACK

from Master

NACK

from Master

Stop Condition

by Master

ACK

from Master

Data Word (n+1) Data Word (n+2) Data Word (n+x)

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

D7 D6 D5 D4 D3 D2 D1 D0 0 D7 D6 D5 D4 D3 D2 D1 D0 0 D7 D6 D5 D4 D3 D2 D1 D0 1

MSB MSB MSB

AT24C64D

Read Operations

9. Device Default Condition from Microchip

The AT24C64D is delivered with the EEPROM array set to logic ‘1’, resulting in FFh data in all locations.

AT24C64D

Device Default Condition from Microchip

10. Packaging Information

10.1 Package Marking Information

AT24C64D: Package Marking Information

Catalog Number Truncation

AT24C64D Truncation Code ###: 64D

Date Codes Voltages

YY = Year Y = Year WW = Work Week of Assembly % = Minimum Voltage

16: 2016 20: 2020 6: 2016 0: 2020 02: Week 2 M: 1.7V min

17: 2017 21: 2021 7: 2017 1: 2021 04: Week 4

18: 2018 22: 2022 8: 2018 2: 2022 ...

19: 2019 23: 2023 9: 2019 3: 2023 52: Week 52

Country of Origin Device Grade Atmel Truncation

CO = Country of Origin H or U: Industrial Grade AT: Atmel

ATM: Atmel

ATML: Atmel

Lot Number or Trace Code

NNN = Alphanumeric Trace Code (2 Characters for Small Packages)

8-lead SOIC

YYWWNNN

###% CO

ATMLHYWW

8-lead TSSOP

YYWWNNN

###%CO

ATHYWW ###

NNN

8-pad XDFN

8-pad UDFN

###

NNN

2.0 x 3.0 mm Body

4 and 6-ball WLCSP

1.5 x 2.0 mm Body

8-ball VFBGA

1.8 x 2.2 mm Body

Note 2: Package drawings are not to scale

Note 1: designates pin 1

###

NNN

###U

WNNN

AT24C64D

Packaging Information

0.25 C A–B D

SEATING

PLANE

TOP VIEW

SIDE VIEW

VIEW A–A

0.10 C

Microchip Technology Drawing No. C04-057-SN Rev D Sheet 1 of 2

For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

Note:

8-Lead Plastic Small Outline (SN) - Narrow, 3.90 mm (.150 In.) Body [SOIC]

NOTE 5

NX b

0.10 C A–B

H 0.23

(L1)

R0.13

VIEW C

SEE VIEW C

NOTE 1

AT24C64D

Packaging Information

Microchip Technology Drawing No. C04-057-SN Rev D Sheet 2 of 2

8-Lead Plastic Small Outline (SN) - Narrow, 3.90 mm (.150 In.) Body [SOIC]

For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

Note:

Foot Angle 0° - 8°

15°-5°

Mold Draft Angle Bottom

15°-5°

Mold Draft Angle Top

0.51-0.31

Lead Width

0.25-0.17

Lead Thickness

1.27-0.40LFoot Length

0.50-0.25hChamfer (Optional)

4.90 BSCDOverall Length

3.90 BSCE1Molded Package Width

6.00 BSCEOverall Width

0.25-0.10

Standoff

--1.25A2Molded Package Thickness

1.75--AOverall Height

1.27 BSC

Pitch

8NNumber of Pins

MAXNOMMINDimension Limits

MILLIMETERSUnits

protrusions shall not exceed 0.15mm per side.

3. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or

REF: Reference Dimension, usually without tolerance, for information purposes only.

BSC: Basic Dimension. Theoretically exact value shown without tolerances.

1. Pin 1 visual index feature may vary, but must be located within the hatched area.

2. § Significant Characteristic

4. Dimensioning and tolerancing per ASME Y14.5M

Notes:

Footprint L1 1.04 REF

5. Datums A & B to be determined at Datum H.

AT24C64D

Packaging Information

RECOMMENDED LAND PATTERN

Microchip Technology Drawing C04-2057-SN Rev B

8-Lead Plastic Small Outline (SN) - Narrow, 3.90 mm Body [SOIC]

BSC: Basic Dimension. Theoretically exact value shown without tolerances.

Notes:

Dimensioning and tolerancing per ASME Y14.5M1.

For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

Note:

Dimension Limits

Units

CContact Pad Spacing

Contact Pitch

MILLIMETERS

1.27 BSC

MIN

MAX

5.40

Contact Pad Length (X8)

Contact Pad Width (X8)

1.55

0.60

NOM

SILK SCREEN

AT24C64D

Packaging Information

Packaging Diagrams and Parameters

8-Lead Plastic Thin Shrink Small Outline (ST) – 4.4 mm Body [TSSOP]

Notes:

1. Pin 1 visual index feature may vary, but must be located within the hatched area.

2. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.15 mm per side.

3. Dimensioning and tolerancing per ASME Y14.5M.

BSC: Basic Dimension. Theoretically exact value shown without tolerances.

REF: Reference Dimension, usually without tolerance, for information purposes only.

Note: For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

Units MILLIMETERS

Dimension Limits MIN NOM MAX

Number of Pins N 8

Pitch e 0.65 BSC

Overall Height A – – 1.20

Molded Package Thickness A2 0.80 1.00 1.05

Standoff A1 0.05 – 0.15

Overall Width E 6.40 BSC

Molded Package Width E1 4.30 4.40 4.50

Molded Package Length D 2.90 3.00 3.10

Foot Length L 0.45 0.60 0.75

Footprint L1 1.00 REF

Foot Angle φ0° – 8°

Lead Thickness c 0.09 – 0.20

Lead Width b 0.19 – 0.30

NOTE 1

1 2

L1 L

Microchip Technology Drawing C04-086B

AT24C64D

Packaging Information

DS00049BC-page 96 2009 Microchip Technology Inc.

Packaging Diagrams and Parameters

Note: For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

AT24C64D

Packaging Information

0.10 C

(DATUM B)

(DATUM A)

SEATING

PLANE

TOP VIEW

SIDE VIEW

NOTE 1

0.10 C A B

0.10 C

0.08 C

Microchip Technology Drawing C04-21355-Q4B Rev A Sheet 1 of 2

For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

Note:

8-Lead Ultra Thin Plastic Dual Flat, No Lead Package (Q4B) - 2x3 mm Body [UDFN]

Atmel Legacy YNZ Package

E2 K

L8X b

0.10 C A B

0.05 C

(A3)

BOTTOM VIEW

AT24C64D

Packaging Information

REF: Reference Dimension, usually without tolerance, for information purposes only.

BSC: Basic Dimension. Theoretically exact value shown without tolerances.

Notes:

Pin 1 visual index feature may vary, but must be located within the hatched area.

Package is saw singulated

Dimensioning and tolerancing per ASME Y14.5M

For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

Note:

Number of Terminals

Overall Height

Terminal Width

Overall Width

Terminal Length

Exposed Pad Width

Terminal Thickness

Pitch

Standoff

Units

Dimension Limits

0.50 BSC

0.152 REF

1.20

0.35

0.18

0.50

0.00

0.25

0.40

1.30

0.55

0.02

3.00 BSC

MILLIMETERS

MIN NOM

1.40

0.45

0.30

0.60

0.05

MAX

K-0.20 -Terminal-to-Exposed-Pad

Overall Length

Exposed Pad Length

D2 1.40

2.00 BSC

1.50 1.60

Microchip Technology Drawing C04-21355-Q4B Rev A Sheet 2 of 2

8-Lead Ultra Thin Plastic Dual Flat, No Lead Package (Q4B) - 2x3 mm Body [UDFN]

Atmel Legacy YNZ Package

AT24C64D

Packaging Information

RECOMMENDED LAND PATTERN

Dimension Limits

Units

Optional Center Pad Width

Optional Center Pad Length

Contact Pitch

1.40

1.60

MILLIMETERS

0.50 BSC

MIN

MAX

Contact Pad Length (X8)

Contact Pad Width (X8)

0.85

0.30

NOM

CContact Pad Spacing 2.90

Contact Pad to Center Pad (X8) G1 0.20

Thermal Via Diameter V

Thermal Via Pitch EV

0.30

1.00

BSC: Basic Dimension. Theoretically exact value shown without tolerances.

Notes:

Dimensioning and tolerancing per ASME Y14.5M

For best soldering results, thermal vias, if used, should be filled or tented to avoid solder loss during

reflow process

For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

Note:

Microchip Technology Drawing C04-21355-Q4B Rev A

8-Lead Ultra Thin Plastic Dual Flat, No Lead Package (Q4B) - 2x3 mm Body [UDFN]

Atmel Legacy YNZ Package

SILK SCREEN X1

ØV

Contact Pad to Contact Pad (X6) G2 0.33

AT24C64D

Packaging Information

DRAWING NO. REV. TITLE GPC

8U3-1 G

7/1/14

8U3-1, 8-ball, 1.50mm x 2.00mm body, 0.50mm pitch,

Very Thin, Fine-Pitch Ball Grid Array Package (VFBGA) GXU

COMMON DIMENSIONS

(Unit of Measure - mm)

SYMBOL MIN NOM MAX NOTE

0.73 0.79 0.85

A1 0.09 0.14 0.19

A2 0.40 0.45 0.50

b 0.20 0.25 0.30 2

1.50 BSC

2.0 BSC

0.50 BSC

e1 0.25 REF

1.00 BSC

d1 0.25 REF

1. This drawing is for general information only.

2. Dimension ‘b’ is measured at maximum solder ball diameter.

3. Solder ball composition shall be 95.5Sn-4.0Ag-.5Cu.

Notes:

SIDE VIEW

PIN 1 BALL PAD CORNER

TOP VIEW

8 SOLDER BALLS

BOTTOM VIEW

(d1)

(e1)

PIN 1 BALL PAD CORNER

(4X)d0.10

d0.08 C

f0.10 C

j n 0.15 mC A B

j n 0.08mC

Note: For the most current package drawings, please see the Microchip Packaging Specification located

at http://www.microchip.com/packaging.

AT24C64D

Packaging Information

GPC DRAWING NO.

REV. TITLE

COMMON DIMENSIONS

(Unit of Measure = mm)

DTP

SYMBOL MIN NOM MAX NOTE

–

0.00

1.70

2.10

0.15

0.26

–

1.80

2.20

0.20

0.40 TYP

1.20 REF

0.30

0.40

0.05

1.90

2.30

0.25

0.35

End View

8ME1 B

9/10/2012

8ME1, 8-pad (1.80mm x 2.20mm body)

Extra Thin DFN (XDFN)

Top View

65 7

PIN #1 ID

0.10

0.15

PIN #1 ID

Side View

Note: For the most current package drawings, please see the Microchip Packaging Specification located

at http://www.microchip.com/packaging.

AT24C64D

Packaging Information

DRAWING NO. REV. TITLE GPC

4U-12 B

2/14/18

4U-12, 4-ball, 2x2 Array, 0.40mm Pitch

Wafer Level Chip Scale Package (WLCSP) with BSC GVF

COMMON DIMENSIONS

(Unit of Measure = mm)

SYMBOL MIN TYP MAX NOTE

A 0.260 0.295 0.330

A1 0.080 0.095 0.110

A2 0.160 0.175 0.190

A3 0.025 REF 3

Contact Microchip for details

d1 0.400 BSC

Contact Microchip for details

e1 0.400 BSC

b 0.170 0.185 0.200

PIN ASSIGNMENT MATRIX

BOTTOM VIEW

TOP VIEW

SIDE VIEW

VCC

SDA

GND

SCL

k0.075 C

-C-

Note: 1. Dimensions are NOT to scale.

2. Solder ball composition is 95.5Sn-4.0Ag-0.5Cu.

3. Product offered with Back Side Coating (BSC)

SEATING PLANE

b (4X)

vd0.015 C

d0.05 C A B

k0.015 (4X)

A1 CORNER A1 CORNER

Note: For the most current package drawings, please see the Microchip Packaging Specification located

at http://www.microchip.com/packaging.

AT24C64D

Packaging Information

DRAWING NO. REV. TITLE GPC

6U-2 C

5/6/15

6U-2, 6-ball, 2x3 Array, 0.40mm pitch

Wafer Level Chip Scale Package (WLCSP) with BSC

GMK

COMMON DIMENSIONS

(Unit of Measure = mm)

SYMBOL MIN TYP MAX NOTE

A 0.260 0.295 0.330

A1 0.080 0.095 0.110

A2 0.160 0.175 0.190

A3 0.025 REF 3

Contact Microchip for details

d1 0.40 BSC

Contact Microchip for details

e1 0.40 BSC

b 0.170

0.185 0.200

TOP VIEW

SIDE VIEW

BOTTOM SIDE

PIN ASSIGNMENT MATRIX

Note: 1. Dimensions are NOT to scale.

2. Solder ball composition is 95.5Sn-4.0Ag-0.5Cu.

3. Product offered with Back Side Coating (BSC)

123

VCC

SCL

GND

SDA

vd0.015 mC

d0.05 mCAB

k0.015 C

k0.075 C

A1 CORNER A1 CORNER

SEATING PLANE

A2 A

Note: For the most current package drawings, please see the Microchip Packaging Specification located

at http://www.microchip.com/packaging.

AT24C64D

Packaging Information

11. Revision History

Revision B (November 2018)

Corrected tPOFF typo from 1 ms to 500 ms. Updated the "Bus Timing" figure. Updated the section content

throughout for clarification. Replaced the 8U2-1 VFBGA Package Outline Drawing with the 8U3-1 VFBGA

Package Outline Drawing. Updated the SOIC, TSSOP and UDFN package drawings to Microchip format.

Corrected Revision A history to further document changes.

Revision A (February 2018)

Updated to the Microchip template. Microchip DS20005937 replaces Atmel document 8805. Corrected

tLOW typo from 400ns to 500ns. Corrected tAA typo from 550ns to 450ns. Updated Package Marking

Information. Removed the 5‑ball WLCSP detail and ordering code. Updated Package Drawing 4U-12.

Updated Product ID System. Updated the “Software Reset” section. Added ESD rating. Removed lead

finish designation. Updated trace code format in package markings. Updated section content throughout

for clarification. Added a figure for “System Configuration Using 2‑Wire Serial EEPROMs”. Added POR

recommendations section.

Atmel Document 8805 Revision D (May 2015)

Added the 4‑ball WLCSP, AT24C64D‑U2UM0B‑T option. Updated the 8S1 package drawing.

Atmel Document 8805 Revision C (February 2015)

Updated the 6‑ball and 5‑ball WLCSP package outline drawings to reflect offering of product with

backside coating.

Atmel Document 8805 Revision B (December 2014)

Added the AT24C64D‑MAHM‑E product offering. Updated the 8X, 8MA2, 5U‑2, and 8U2‑1 package

outline drawings and the ordering information.

Atmel Document 8805 Revision A (June 2013)

Initial document release.

AT24C64D

Revision History

The Microchip Web Site

Microchip provides online support via our web site at http://www.microchip.com/. This web site is used as

a means to make files and information easily available to customers. Accessible by using your favorite

Internet browser, the web site contains the following information:

•Product Support – Data sheets and errata, application notes and sample programs, design

resources, user’s guides and hardware support documents, latest software releases and archived

software

•General Technical Support – Frequently Asked Questions (FAQ), technical support requests,

online discussion groups, Microchip consultant program member listing

•Business of Microchip – Product selector and ordering guides, latest Microchip press releases,

listing of seminars and events, listings of Microchip sales offices, distributors and factory

representatives

Customer Change Notification Service

Microchip’s customer notification service helps keep customers current on Microchip products.

Subscribers will receive e-mail notification whenever there are changes, updates, revisions or errata

related to a specified product family or development tool of interest.

To register, access the Microchip web site at http://www.microchip.com/. Under “Support”, click on

“Customer Change Notification” and follow the registration instructions.

Customer Support

Users of Microchip products can receive assistance through several channels:

• Distributor or Representative

• Local Sales Office

• Field Application Engineer (FAE)

• Technical Support

Customers should contact their distributor, representative or Field Application Engineer (FAE) for support.

Local sales offices are also available to help customers. A listing of sales offices and locations is included

in the back of this document.

Technical support is available through the web site at: http://www.microchip.com/support

AT24C64D

Product Identification System

To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.

Product Family

24C = Standard I2C-compatible

Serial EEPROM

Device Density

Shipping Carrier Option

Device Grade or

Wafer/Die Thickness

64= 64 Kilobit

B = Bulk (Tubes)

T = Tape and Reel, Standard Quantity Option

E = Tape and Reel, Extended Quantity Option

Operating Voltage

M = 1.7V to 5.5V

H or U = Industrial Temperature Range

(-40°C to +85°C)

11 = 11mil Wafer Thickness

Package Option

SS = SOIC

X = TSSOP

MA = 2.0mm x 3.0mm UDFN

ME = 1.5mm x 2.0mm XDFN

U = 6-ball, 2x3 Grid Array, WLCSP

U2 = 4-ball, 2x2 Grid Array, WLCSP

C = VFBGA

WWU = Wafer Unsawn

AT24C64D-SSHMxx-B

Device Revision

Product Variation

xx = Applies to select packages only.

Examples

Device Package Package

Drawing

Code

Package

Option

Shipping Carrier Option Device Grade

AT24C64D‑SSHM‑B SOIC SN SS Bulk (Tubes) Industrial

Temperature

(-40°C to +85°C)

AT24C64D‑SSHM‑T SOIC SN SS Tape and Reel

AT24C64D‑XHM‑T TSSOP ST X Tape and Reel

AT24C64D‑MAHM‑T UDFN Q4B MA Tape and Reel

AT24C64D‑MAHM‑E UDFN Q4B MA Extended Qty. Tape and

Reel

AT24C64D‑MEHM‑T XDFN 8ME1 ME Tape and Reel

AT24C64D‑CUM‑T VFBGA 8U3‑1 C Tape and Reel

AT24C64D‑UUM0B‑T WLCSP 6U‑2 U Tape and Reel

AT24C64D‑U2UM0B‑T WLCSP 4U‑12 U2 Tape and Reel

AT24C64D

Microchip Devices Code Protection Feature

Note the following details of the code protection feature on Microchip devices:

• Microchip products meet the specification contained in their particular Microchip Data Sheet.

• Microchip believes that its family of products is one of the most secure families of its kind on the

market today, when used in the intended manner and under normal conditions.

• There are dishonest and possibly illegal methods used to breach the code protection feature. All of

these methods, to our knowledge, require using the Microchip products in a manner outside the

operating specifications contained in Microchip’s Data Sheets. Most likely, the person doing so is

engaged in theft of intellectual property.

• Microchip is willing to work with the customer who is concerned about the integrity of their code.

• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their

code. Code protection does not mean that we are guaranteeing the product as “unbreakable.”

Code protection is constantly evolving. We at Microchip are committed to continuously improving the

code protection features of our products. Attempts to break Microchip’s code protection feature may be a

violation of the Digital Millennium Copyright Act. If such acts allow unauthorized access to your software

or other copyrighted work, you may have a right to sue for relief under that Act.

Legal Notice

Information contained in this publication regarding device applications and the like is provided only for

your convenience and may be superseded by updates. It is your responsibility to ensure that your

application meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR

WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY

OR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS

CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE.

Microchip disclaims all liability arising from this information and its use. Use of Microchip devices in life

support and/or safety applications is entirely at the buyer’s risk, and the buyer agrees to defend,

indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting

from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual

property rights unless otherwise stated.

Trademarks

The Microchip name and logo, the Microchip logo, AnyRate, AVR, AVR logo, AVR Freaks, BitCloud,

chipKIT, chipKIT logo, CryptoMemory, CryptoRF, dsPIC, FlashFlex, flexPWR, Heldo, JukeBlox, KeeLoq,

Kleer, LANCheck, LINK MD, maXStylus, maXTouch, MediaLB, megaAVR, MOST, MOST logo, MPLAB,

OptoLyzer, PIC, picoPower, PICSTART, PIC32 logo, Prochip Designer, QTouch, SAM-BA, SpyNIC, SST,

SST Logo, SuperFlash, tinyAVR, UNI/O, and XMEGA are registered trademarks of Microchip Technology

Incorporated in the U.S.A. and other countries.

ClockWorks, The Embedded Control Solutions Company, EtherSynch, Hyper Speed Control, HyperLight

Load, IntelliMOS, mTouch, Precision Edge, and Quiet-Wire are registered trademarks of Microchip

Technology Incorporated in the U.S.A.

Adjacent Key Suppression, AKS, Analog-for-the-Digital Age, Any Capacitor, AnyIn, AnyOut, BodyCom,

CodeGuard, CryptoAuthentication, CryptoAutomotive, CryptoCompanion, CryptoController, dsPICDEM,

dsPICDEM.net, Dynamic Average Matching, DAM, ECAN, EtherGREEN, In-Circuit Serial Programming,

ICSP, INICnet, Inter-Chip Connectivity, JitterBlocker, KleerNet, KleerNet logo, memBrain, Mindi, MiWi,

AT24C64D

motorBench, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach, Omniscient

Code Generation, PICDEM, PICDEM.net, PICkit, PICtail, PowerSmart, PureSilicon, QMatrix, REAL ICE,

Ripple Blocker, SAM-ICE, Serial Quad I/O, SMART-I.S., SQI, SuperSwitcher, SuperSwitcher II, Total

Endurance, TSHARC, USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA, and ZENA are

trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.

SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.

Silicon Storage Technology is a registered trademark of Microchip Technology Inc. in other countries.

GestIC is a registered trademark of Microchip Technology Germany II GmbH & Co. KG, a subsidiary of

Microchip Technology Inc., in other countries.

All other trademarks mentioned herein are property of their respective companies.

ISBN: 978-1-5224-3817-5

Quality Management System Certified by DNV

ISO/TS 16949

Microchip received ISO/TS-16949:2009 certification for its worldwide headquarters, design and wafer

fabrication facilities in Chandler and Tempe, Arizona; Gresham, Oregon and design centers in California

and India. The Company’s quality system processes and procedures are for its PIC® MCUs and dsPIC®

DSCs, KEELOQ® code hopping devices, Serial EEPROMs, microperipherals, nonvolatile memory and

analog products. In addition, Microchip’s quality system for the design and manufacture of development

systems is ISO 9001:2000 certified.

AT24C64D

AMERICAS ASIA/PACIFIC ASIA/PACIFIC EUROPE

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