MICROCHIP 24LCS21_13

Not recommended for new designs –
Please use 24LCS21A.
24LCS21
1K 2.5V Dual Mode I2C™ Serial EEPROM
Package Types
™
• Completely implements DDC1 /DDC2 interface
for monitor identification
• Hardware write-protect pin
• Single supply with operation down to 2.5V
• Low-power CMOS technology:
- 1 mA active current, typical
- 10 A standby current, typical at 5.5V
• 2-wire serial interface bus, I2C™ compatible (SCL)
• Self-timed write cycle (including auto-erase)
• Page-write buffer for up to 8 bytes
• 100 kHz (2.5V) and 400 kHz (5V) compatibility
(SCL)
• 1,000,000 erase/write cycles ensured
• Data retention > 200 years
• 8-pin PDIP and SOIC package
• Available for extended temperature ranges:
- Commercial (C):
0°C to +70°C
- Industrial (I)
-40°C to +85°C
PDIP
NC
1
NC
2
WP
3
VSS
4
NC
1
NC
2
WP
3
VSS
4
24LCS21
™
8
VCC
7
VCLK
6
SCL
5
SDA
8
VCC
7
VCLK
6
SCL
5
SDA
SOIC
24LCS21
Features:
Description:
The Microchip Technology Inc. 24LCS21 is a 128 x 8-bit
dual-mode Electrically Erasable PROM. This device is
designed for use in applications requiring storage and
serial transmission of configuration and control information. Two modes of operation have been implemented:
Transmit-Only mode and Bidirectional mode. Upon
power-up, the device will be in the Transmit-Only mode,
sending a serial bit stream of the entire memory array
contents, clocked by the VCLK pin. A valid high-to-low
transition on the SCL pin will cause the device to enter
the Bidirectional mode, with byte selectable read/write
capability of the memory array in standard I2C protocol.
The 24LCS21 also enables the user to write-protect the
entire memory contents using its write-protect pin. The
24LCS21 is available in a standard 8-pin PDIP and
SOIC package in both commercial and industrial
temperature ranges.
 1995-2012 Microchip Technology Inc.
Block Diagram
WP
HV Generator
I/O
Control
Logic
Memory
Control
Logic
EEPROM
XDEC
Array
Page Latches
SDA SCL
YDEC
VCLK
Sense Amp
R/W Control
VCC
VSS
DS21127G-page 1
24LCS21
1.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings(†)
VCC .............................................................................................................................................................................7.0V
All inputs and outputs w.r.t. VSS ........................................................................................................ -0.6V to VCC + 1.0V
Storage temperature ...............................................................................................................................-65C to +150C
Ambient temperature with power applied ................................................................................................-40C to +125C
Soldering temperature of leads (10 seconds) .......................................................................................................+300C
ESD protection on all pins 4 kV
† NOTICE: 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 operational listings of this specification is not implied. Exposure to Absolute Maximum Rating
conditions for extended periods may affect device reliability.
TABLE 1-1:
DC CHARACTERISTICS
DC CHARACTERISTICS
Parameter
VCC = +2.5V to 5.5V
Commercial (C): TA = 0C to +70C
Industrial
(I): TA = -40C to +85C
Symbol
Min
SCL and SDA pins:
High-level input voltage
Low-level input voltage
VIH
VIL
0.7 VCC
Input levels on VCLK pin:
High-level input voltage
Low-level input voltage
VIH
VIL
2.0
.05 VCC
Hysteresis of Schmitt Trigger inputs
VHYS
Low-level output voltage
VOL1
Low-level output voltage
VOL2
Input leakage current
Output leakage current
Pin capacitance (all inputs/outputs)
Operating current
Standby current
Note 1:
Max
Units
0.3 VCC
V
V
0.8
0.2 VCC
V
V
Conditions
VCC  2.7V (Note 1)
VCC < 2.7V (Note 1)
—
V
(Note 1)
0.4
V
IOL = 3 mA, VCC = 2.5V (Note 1)
0.6
V
IOL = 6 mA, VCC = 2.5V
ILI
-10
10
A
VIN = 0.1V to VCC
ILO
-10
10
A
VOUT = 0.1V to VCC
10
pF
VCC = 5.0V (Note 1),
TA = 25C, FCLK = 1 MHz
CINT
ICC Write
ICC Read
—
—
3
1
mA
mA
VCC = 5.5V, SCL = 400 kHz
ICCS
—
30
100
A
A
VCC = 3.0V, SDA = SCL = VCC
VCC = 5.5V, SDA = SCL = VCC
VCLK = VSS
This parameter is periodically sampled and not 100% tested.
DS21127G-page 2
 1995-2012 Microchip Technology Inc.
24LCS21
TABLE 1-2:
AC CHARACTERISTICS
VCC = 2.5-5.5V
Parameter
VCC = 4.5-5.5V
Symbol
Units
Min
Max
Min
Max
Clock frequency
FCLK
0
100
0
400
kHz
Clock high time
THIGH
4000
—
600
—
ns
Clock low time
TLOW
4700
—
1300
—
ns
TR
—
1000
—
300
ns
SDA and SCL rise time
SDA and SCL fall time
Remarks
(Note 1)
TF
—
300
—
300
ns
(Note 1)
Start condition hold time
THD:STA
4000
—
600
—
ns
After this period the first
clock pulse is generated
Start condition setup time
TSU:STA
4700
—
600
—
ns
Only relevant for repeated
Start condition
Data input hold time
THD:DAT
0
—
0
—
ns
(Note 2)
Data input setup time
TSU:DAT
250
—
100
—
ns
Stop condition setup time
TSU:STO
4000
—
600
—
ns
TAA
—
3500
—
900
ns
(Note 2)
Bus free time
TBUF
4700
—
1300
—
ns
Time the bus must be free
before a new transmission
can start
Output fall time from VIH
minimum to VIL maximum
TOF
—
250
20 + 0.1
CB
250
ns
(Note 1), CB 100 pF
Input filter spike suppression
(SDA and SCL pins)
TSP
—
100
—
50
ns
(Note 3)
Write cycle time
TWR
—
10
—
10
ms
Byte or Page mode
TVAA
—
2000
—
1000
ns
Output valid from clock
Transmit-Only Mode Parameters
Output valid from VCLK
VCLK high time
TVHIGH
4000
—
600
—
ns
VCLK low time
TVLOW
4700
—
1300
—
ns
VCLK setup time
TVHST
0
—
0
—
ns
VCLK hold time
TSPVL
4000
—
600
—
ns
Mode transition time
TVHZ
—
500
—
500
ns
Transmit-only power-up time
TVPU
0
—
0
—
ns
Input filter spike suppression
(VCLK pin)
TSPV
—
100
—
100
ns
—
1M
—
1M
—
cycles
Endurance
Note 1:
2:
3:
4:
25°C, VCC = 5.0V, Block
mode (Note 4)
Not 100% tested. CB = total capacitance of one bus line in pF.
As a transmitter, the device must provide an internal minimum delay time to bridge the undefined region
(minimum 300 ns) of the falling edge of SCL to avoid unintended generation of Start or Stop conditions.
The combined TSP and VHYS specifications are due to Schmitt Trigger inputs which provide noise and
spike suppression. This eliminates the need for a TI specification for standard operation.
This parameter is not tested but ensured by characterization. For endurance estimates in a specific
application, please consult the Total Endurance™ Model which can be obtained from Microchip’s web site
at www.microchip.com.
 1995-2012 Microchip Technology Inc.
DS21127G-page 3
24LCS21
2.0
FUNCTIONAL DESCRIPTION
The 24LCS21 operates in two modes, the TransmitOnly mode and the Bidirectional mode. There is a
separate two-wire protocol to support each mode, each
having a separate clock input but sharing a common
data line (SDA). The device enters the Transmit-Only
mode upon power-up. In this mode, the device
transmits data bits on the SDA pin in response to a
clock signal on the VCLK pin. The device will remain in
this mode until a valid high-to-low transition is placed
on the SCL input. When a valid transition on SCL is
recognized, the device will switch into the Bidirectional
mode. The only way to switch the device back to the
Transmit-Only mode is to remove power from the
device.
2.1
Transmit-Only Mode
The device will power-up in the Transmit-Only mode at
address 00h. This mode supports a unidirectional twowire protocol for continuous transmission of the
contents of the memory array. This device requires that
it be initialized prior to valid data being sent in the
FIGURE 2-1:
Transmit-Only mode (see Initialization Procedure,
below). In this mode, data is transmitted on the SDA pin
in 8-bit bytes, with each byte followed by a ninth, null bit
(Figure 2-1). The clock source for the Transmit-Only
mode is provided on the VCLK pin, and a data bit is output on the rising edge on this pin. The eight bits in each
byte are transmitted Most Significant bit first. Each byte
within the memory array will be output in sequence.
When the last byte in the memory array is transmitted,
the internal Address Pointers will wrap around to the
first memory location (00h) and continue. The
Bidirectional mode clock (SCL) pin must be held high
for the device to remain in the Transmit-Only mode.
2.2
Initialization Procedure
After VCC has stabilized, the device will be in the Transmit-Only mode. Nine clock cycles on the VCLK pin must
be given to the device for it to perform internal synchronization. During this period, the SDA pin will be in a
high-impedance state. On the rising edge of the tenth
clock cycle, the device will output the first valid data bit
which will be the Most Significant bit in address 00h.
(Figure 2-2).
TRANSMIT-ONLY MODE
SCL
TVAA
TVAA
SDA
Null Bit
Bit 1 (LSB)
Bit 1 (MSB)
Bit 7
VCLK
TVHIGH
FIGURE 2-2:
TVLOW
DEVICE INITIALIZATION
VCC
SCL
SDA
TVAA
High-impedance for 9 clock cycles
TVAA
Bit 8
Bit 7
TVPU
VCLK
DS21127G-page 4
1
2
8
9
10
11
 1995-2012 Microchip Technology Inc.
24LCS21
3.0
BIDIRECTIONAL MODE
3.1
The 24LCS21 can be switched into the Bidirectional
mode (Figure 3-1) by applying a valid high-to-low
transition on the Bidirectional mode clock (SCL). When
the device has been switched into the Bidirectional
mode, the VCLK input is disregarded, with the exception
that a logic high level is required to enable write capability. This mode supports a two-wire bidirectional data
transmission protocol (I2C™). In this protocol, a device
that sends data on the bus is defined to be the transmitter and a device that receives data from the bus is
defined to be the receiver. The bus must be controlled
by a master device that generates the Bidirectional
mode clock (SCL), controls access to the bus and generates the Start and Stop conditions, while the
24LCS21 acts as the slave. Both master and slave can
operate as transmitter or receiver, but the master
device determines which mode is activated.
In this mode, the 24LCS21 only responds to
commands for device ‘1010 000X’.
Bidirectional Mode Bus
Characteristics
The following bus protocol has been defined:
• Data transfer may be initiated only when the bus
is not busy.
• During data transfer, the data line must remain
stable whenever the clock line is high. Changes in
the data line while the clock line is high will be
interpreted as a Start or Stop condition.
Accordingly, the following bus conditions have been
defined (Figure 3-2).
3.1.1
BUS NOT BUSY (A)
Both data and clock lines remain high.
3.1.2
START DATA TRANSFER (B)
A high-to-low transition of the SDA line while the clock
(SCL) is high determines a Start condition. All
commands must be preceded by a Start condition.
3.1.3
STOP DATA TRANSFER (C)
A low-to-high transition of the SDA line while the clock
(SCL) is high determines a Stop condition. All
operations must be ended with a Stop condition.
FIGURE 3-1:
MODE TRANSITION
Transmit-Only mode
Bidirectional mode
SCL
TVHZ
SDA
VCLK
FIGURE 3-2:
SCL
(A)
DATA TRANSFER SEQUENCE ON THE SERIAL BUS
(B)
(D)
Start
Condition
Address or
Acknowledge
Valid
(D)
(C)
(A)
SDA
 1995-2012 Microchip Technology Inc.
Data
Allowed
to Change
Stop
Condition
DS21127G-page 5
24LCS21
3.1.4
DATA VALID (D)
3.1.5
The state of the data line represents valid data when,
after a Start condition, the data line is stable for the
duration of the high period of the clock signal.
Each receiving device, when addressed, is obliged to
generate an acknowledge after the reception of each
byte. The master device must generate an extra clock
pulse which is associated with this Acknowledge bit.
The data on the line must be changed during the low
period of the clock signal. There is one clock pulse per
bit of data.
Note:
Each data transfer is initiated with a Start condition and
terminated with a Stop condition. The number of the
data bytes transferred between the Start and Stop
conditions is determined by the master device and is
theoretically unlimited, although only the last eight will
be stored when doing a write operation. When an
overwrite does occur, it will replace data in a first-in
first-out (FIFO) fashion.
Note:
The 24LCS21 does not generate any
Acknowledge
bits
if
an
internal
programming cycle is in progress.
The device that acknowledges has to pull down the
SDA line during the acknowledge clock pulse in such a
way that the SDA line is stable low during the high
period of the acknowledge related clock pulse. Of
course, setup and hold times must be taken into
account. A master must signal an end of data to the
slave by not generating an Acknowledge bit on the last
byte that has been clocked out of the slave. In this
case, the slave must leave the data line high to enable
the master to generate the Stop condition.
Once switched into Bidirectional mode,
the 24LCS21 will remain in that mode
until power goes away. Removing power
is the only way to reset the 24LCS21 into
the Transmit-Only mode.
FIGURE 3-3:
ACKNOWLEDGE
BUS TIMING START/STOP
VHYS
SCL
THD:STA
TSU:STA
TSU:STO
SDA
Start
FIGURE 3-4:
Stop
BUS TIMING DATA
TF
TR
THIGH
TLOW
SCL
TSU:STA
THD:DAT
TSU:DAT
THD:STA
SDA
IN
TSP
TSU:STO
TBUF
TAA
TAA
SDA
OUT
DS21127G-page 6
 1995-2012 Microchip Technology Inc.
24LCS21
3.1.6
SLAVE ADDRESS
FIGURE 3-5:
After generating a Start condition, the bus master
transmits the slave address consisting of a 7-bit device
code ‘1010000’ for the 24LCS21.
Start
Read/Write
The eighth bit of the slave address determines whether
the master device wants to read or write to the
24LCS21 (Figure 3-5).
The 24LCS21 monitors the bus for its corresponding
slave address continuously. It generates an
Acknowledge bit if the slave address was true and it is
not in a programming mode.
Operation
Slave Address
R/W
Read
1010000
1
Write
1010000
0
 1995-2012 Microchip Technology Inc.
CONTROL BYTE
ALLOCATION
Slave Address
1
0
1
0
0
R/W
0
A
0
DS21127G-page 7
24LCS21
4.0
WRITE OPERATION
4.1
Byte Write
After receiving another Acknowledge signal from the
24LCS21, the master device will transmit the data word
to be written into the addressed memory location. The
24LCS21 acknowledges again and the master
generates a Stop condition. This initiates the internal
write cycle, and during this time the 24LCS21 will not
generate Acknowledge signals (Figure 4-1).
Following the Start signal from the master, the slave
address (4 bits), three zero bits (000) and the R/W bit,
which is a logic low, are placed onto the bus by the
master transmitter. This indicates to the addressed
slave receiver that a byte with a word address will
follow after it has generated an Acknowledge bit during
the ninth clock cycle. Therefore, the next byte
transmitted by the master is the word address and will
be written into the Address Pointer of the 24LCS21.
FIGURE 4-1:
It is required that VCLK be held at a logic high level
during command and data transfer in order to program
the device. This applies to both byte write and page
write operation. Note, however, that the VCLK is ignored
during the self-timed program operation. Changing
VCLK from high-to-low during the self-timed program
operation will not halt programming of the device.
BYTE WRITE
S
T
A
R
T
Bus Activity
Activity
SDA Line
Word
Address
Control
Byte
S
T
O
P
Data
S
P
A
C
K
A
C
K
Bus Activity
A
C
K
VCLK
FIGURE 4-2:
VCLK WRITE ENABLE TIMING
SCL
THD:STA
SDA
IN
TSU:STO
VCLK
TVHST
DS21127G-page 8
TSPVL
 1995-2012 Microchip Technology Inc.
24LCS21
4.2
Page Write
The write control byte, word address and the first data
byte are transmitted to the 24LCS21 in the same way
as in a byte write. But instead of generating a Stop
condition, the master transmits up to eight data bytes to
the 24LCS21, which are temporarily stored in the onchip page buffer and will be written into the memory
after the master has transmitted a Stop condition. After
the receipt of each word, the three lower order Address
Pointer bits are internally incremented by one. The
higher order five bits of the word address remains
constant. If the master should transmit more than eight
words prior to generating the Stop condition, the
address counter will roll over and the previously
received data will be overwritten. As with the byte write
operation, once the Stop condition is received an
internal write cycle will begin (Figure 5-2).
 1995-2012 Microchip Technology Inc.
It is required that VCLK be held at a logic high level
during command and data transfer in order to program
the device. This applies to both byte write and page
write operation. Note, however, that the VCLK is ignored
during the self-timed program operation. Changing
VCLK from high-to-low during the self-timed program
operation will not halt programming of the device.
Note:
Page write operations are limited to writing
bytes within a single physical page,
regardless of the number of bytes actually
being written. Physical page boundaries
start at addresses that are integer
multiples of the page buffer size (or ‘page
size’) and end at addresses that are
integer multiples of [page size – 1]. If a
page Write command attempts to write
across a physical page boundary, the
result is that the data wraps around to the
beginning of the current page (overwriting
data previously stored there), instead of
being written to the next page as might be
expected. It is therefore necessary for the
application software to prevent page write
operations that would attempt to cross a
page boundary.
DS21127G-page 9
24LCS21
5.0
ACKNOWLEDGE POLLING
FIGURE 5-1:
Since the device will not acknowledge during a write
cycle, this can be used to determine when the cycle is
complete (this feature can be used to maximize bus
throughput). Once the Stop condition for a Write
command has been issued from the master, the device
initiates the internally timed write cycle. ACK polling
can be initiated immediately. This involves the master
sending a Start condition followed by the control byte
for a Write command (R/W = 0). If the device is still
busy with the write cycle, then no ACK will be returned.
If the cycle is complete, then the device will return the
ACK and the master can then proceed with the next
Read or Write command. See Figure 5-1 for the flow
diagram.
ACKNOWLEDGE
POLLING FLOW
Send
Write Command
Send Stop
Condition to
Initiate Write Cycle
Send Start
Send Control Byte
with R/W = 0
Did Device
Acknowledge
(ACK = 0)?
No
Yes
Next
Operation
FIGURE 5-2:
PAGE WRITE
Bus
Activity
Master
S
T
A
R
T
SDA Line
S
Bus
Activity
Word
Address
Control
Byte
S
T
O
P
Data n + 7
Data n + 1
Data (n)
P
A
C
K
A
C
K
A
C
K
A
C
K
A
C
K
VCLK
DS21127G-page 10
 1995-2012 Microchip Technology Inc.
24LCS21
6.0
WRITE PROTECTION
7.0
When using the 24LCS21 in the Bidirectional mode, the
VCLK pin operates as the write-protect control pin. Setting VCLK high allows normal write operations, while
setting VCLK low prevents writing to any location in the
array. Connecting the VCLK pin to VSS would allow the
24LCS21 to operate as a serial ROM, although this
configuration would prevent using the device in the
Transmit-Only mode.
Additionally, pin 3 performs a flexible write-protect
function. The 24LCS21 contains a write protection
control fuse whose factory default state is cleared.
Writing any data to address 7Fh (normally the
checksum in DDC applications) sets the fuse which
enables the WP pin. Until this fuse is set, the 24LCS21
is always write enabled (if VCLK = 1). After the fuse is
set, the write capability of the 24LCS21 is determined
by WP (Figure 6-1).
TABLE 6-1:
WRITE-PROTECT TRUTH
TABLE
VCLK
WP
Add. 7Fh
Written
0
X
X
Mode
Read-only
READ OPERATION
Read operations are initiated in the same way as write
operations with the exception that the R/W bit of the
slave address is set to one. There are three basic types
of read operations: current address read, random read
and sequential read.
7.1
Current Address Read
The 24LCS21 contains an address counter that
maintains the address of the last word accessed,
internally incremented by one. Therefore, if the
previous access (either a read or write operation) was
to address n, the next current address read operation
would access data from address n + 1. Upon receipt of
the slave address with R/W bit set to one, the 24LCS21
issues an acknowledge and transmits the eight-bit data
word. The master will not acknowledge the transfer, but
does generate a Stop condition and the 24LCS21
discontinues transmission (Figure 7-1).
FIGURE 7-1:
1
X
No
R/W
Bus Activity
Master
1
1/open
Yes
R/W
SDA Line
1
0
Yes
Read-only
CURRENT ADDRESS
READ
S
T
A
R
T
S10100001
Control
Byte
Bus Activity
7.2
S
T
O
P
Data n
P
A
C
K
N
O
A
C
K
Random Read
Random read operations allow the master to access
any memory location in a random manner. To perform
this type of read operation, first the word address must
be set. This is done by sending the word address to the
24LCS21 as part of a write operation. After the word
address is sent, the master generates a Start condition
following the acknowledge. This terminates the write
operation, but not before the internal Address Pointer is
set. Then the master issues the control byte again but
with the R/W bit set to a one. The 24LCS21 will then
issue an acknowledge and transmits the eight-bit data
word. The master will not acknowledge the transfer, but
does generate a Stop condition and the 24LCS21
discontinues transmission (Figure 7-2).
 1995-2012 Microchip Technology Inc.
DS21127G-page 11
24LCS21
FIGURE 7-2:
RANDOM READ
Bus Activity
Master
S
T
A
R
T
SDA Line
S 1 0 1 0 0 0 0 0
Bus Activity
Control
Byte
S
T
A
R
T
Word
Address
Control
Byte
S
T
O
P
Data n
S 1 0 1 0 0 0 0 1
A
C
K
A
C
K
P
A
C
K
N
O
A
C
K
7.3
Sequential Read
Sequential reads are initiated in the same way as a
random read except that after the 24LCS21 transmits
the first data byte, the master issues an acknowledge
as opposed to a Stop condition in a random read. This
directs the 24LCS21 to transmit the next sequentially
addressed 8-bit word (Figure 8-1).
To provide sequential reads, the 24LCS21 contains an
internal Address Pointer which is incremented by one
at the completion of each operation. This Address
Pointer allows the entire memory contents to be serially
read during one operation.
7.4
Noise Protection
The 24LCS21 employs a VCC threshold detector circuit
which disables the internal erase/write logic if the VCC
is below 1.5 volts at nominal conditions.
The SDA, SCL and VCLK inputs have Schmitt Trigger
and filter circuits which suppress noise spikes to assure
proper device operation, even on a noisy bus.
DS21127G-page 12
 1995-2012 Microchip Technology Inc.
24LCS21
8.0
PIN DESCRIPTIONS
TABLE 8-1:
8.1
8.2
This pin is the clock input for the Bidirectional mode,
and is used to synchronize data transfer to and from the
device. It is also used as the signaling input to switch
the device from the Transmit-Only mode to the
Bidirectional mode. It must remain high for the chip to
continue operation in the Transmit-Only mode.
PIN FUNCTION TABLE
Name
Function
WP
Write-protect (active low)
SCL
VSS
Ground
SDA
Serial Address/Data I/O
SCL
Serial Clock (Bidirectional mode)
VCLK
Serial Clock (Transmit-Only mode)
VCC
+2.5V to 5.5V Power Supply
NC
No Connection
8.3
VCLK
This pin is the clock input for the Transmit-Only mode
(DDC1). In the Transmit-Only mode, each bit is clocked
out on the rising edge of this signal. In the Bidirectional
mode, a high logic level is required on this pin to enable
write capability.
SDA
8.4
This pin is used to transfer addresses and data into and
out of the device, when the device is in the Bidirectional
mode. In the Transmit-Only mode, which only allows
data to be read from the device, data is also transferred
on the SDA pin. This pin is an open drain terminal,
therefore the SDA bus requires a pull-up resistor to
VCC (typical 10 K for 100 kHz, 2 K for 400 kHz).
WP
This pin is used for flexible write protection of the
24LCS21. When the last memory location (7Fh) is
written with any data, this pin is enabled and
determines the write capability of the 24LCS21
(Figure 6-1).
For normal data transfer in the Bidirectional mode, SDA
is allowed to change only during SCL low. Changes
during SCL high are reserved for indicating the Start
and Stop conditions.
FIGURE 8-1:
SEQUENTIAL READ
Bus Activity
Master
Data n
Data n+2
Data n+1
S
T
O
P
Data n+X
Control
Byte
P
SDA Line
Bus Activity
A
C
K
A
C
K
A
C
K
A
C
K
N
O
A
C
K
 1995-2012 Microchip Technology Inc.
DS21127G-page 13
24LCS21
9.0
PACKAGING INFORMATION
9.1
Package Marking Information
8-Lead PDIP
Example
XXXXXXXX
XXXXXNNN
YYWW
24LCS21
017
0410
8-Lead SOIC (.150”)
XXXXXXXX
XXXXYYWW
NNN
Legend: XX...X
Y
YY
WW
NNN
e3
*
Note:
DS21127G-page 14
Example
24LCS21
/SN0410
017
Customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
 1995-2012 Microchip Technology Inc.
24LCS21
8-Lead Plastic Dual In-line (P) – 300 mil Body (PDIP)
Note:
For the most current package drawings, please see the Microchip Packaging Specification located
at http://www.microchip.com/packaging
E1
D
2
n
1

E
A2
A
L
c
A1

B1
p
eB
B
Units
Dimension Limits
n
p
INCHES*
NOM
8
.100
.155
.130
MAX
MILLIMETERS
NOM
8
2.54
3.56
3.94
2.92
3.30
0.38
7.62
7.94
6.10
6.35
9.14
9.46
3.18
3.30
0.20
0.29
1.14
1.46
0.36
0.46
7.87
9.40
5
10
5
10
MAX
Number of Pins
Pitch
Top to Seating Plane
A
.140
.170
4.32
Molded Package Thickness
A2
.115
.145
3.68
Base to Seating Plane
A1
.015
Shoulder to Shoulder Width
E
.300
.313
.325
8.26
Molded Package Width
E1
.240
.250
.260
6.60
Overall Length
D
.360
.373
.385
9.78
Tip to Seating Plane
L
.125
.130
.135
3.43
c
Lead Thickness
.008
.012
.015
0.38
Upper Lead Width
B1
.045
.058
.070
1.78
Lower Lead Width
B
.014
.018
.022
0.56
eB
Overall Row Spacing
§
.310
.370
.430
10.92

Mold Draft Angle Top
5
10
15
15

Mold Draft Angle Bottom
5
10
15
15
* Controlling Parameter
§ Significant Characteristic
Notes:
Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010” (0.254mm) per side.
JEDEC Equivalent: MS-001
Drawing No. C04-018
 1995-2012 Microchip Technology Inc.
MIN
MIN
DS21127G-page 15
24LCS21
8-Lead Plastic Small Outline (SN) – Narrow, 150 mil Body (SOIC)
Note:
For the most current package drawings, please see the Microchip Packaging Specification located
at http://www.microchip.com/packaging
E
E1
p
D
2
B
n
1

h
45
c
A2
A


L
Units
Dimension Limits
n
p
INCHES*
NOM
8
.050
.061
.056
.007
.237
.154
.193
.015
.025
4
.009
.017
12
12
MAX
MILLIMETERS
NOM
8
1.27
1.35
1.55
1.32
1.42
0.10
0.18
5.79
6.02
3.71
3.91
4.80
4.90
0.25
0.38
0.48
0.62
0
4
0.20
0.23
0.33
0.42
0
12
0
12
MAX
Number of Pins
Pitch
Overall Height
A
.053
.069
1.75
Molded Package Thickness
A2
.052
.061
1.55
Standoff
§
A1
.004
.010
0.25
Overall Width
E
.228
.244
6.20
Molded Package Width
.146
.157
3.99
E1
Overall Length
D
.189
.197
5.00
Chamfer Distance
h
.010
.020
0.51
Foot Length
L
.019
.030
0.76

Foot Angle
0
8
8
c
Lead Thickness
.008
.010
0.25
Lead Width
B
.013
.020
0.51

Mold Draft Angle Top
0
15
15

Mold Draft Angle Bottom
0
15
15
* Controlling Parameter
§ Significant Characteristic
Notes:
Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010” (0.254mm) per side.
JEDEC Equivalent: MS-012
Drawing No. C04-057
DS21127G-page 16
MIN
A1
MIN
 1995-2012 Microchip Technology Inc.
24LCS21
APPENDIX A:
REVISION HISTORY
Revision E
Added note to page 1 header (Not recommended for
new designs).
Added Section 9.0: Package Marking Information.
Added On-line Support page.
Updated document format.
Revision F
Revised Section 8.4
Revision G
Added a note to each package outline drawing.
 1995-2012 Microchip Technology Inc.
DS21127G-page 17
24LCS21
NOTES:
DS21127G-page 18
 1995-2012 Microchip Technology Inc.
24LCS21
THE MICROCHIP WEB SITE
CUSTOMER SUPPORT
Microchip provides online support via our WWW site at
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:
Users of Microchip products can receive assistance
through several channels:
• 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
•
•
•
•
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://microchip.com/support
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
www.microchip.com. Under “Support”, click on
“Customer Change Notification” and follow the
registration instructions.
 1995-2012 Microchip Technology Inc.
DS21127G-page 19
24LCS21
READER RESPONSE
It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip
product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our
documentation can better serve you, please FAX your comments to the Technical Publications Manager at
(480) 792-4150.
Please list the following information, and use this outline to provide us with your comments about this document.
TO:
Technical Publications Manager
RE:
Reader Response
Total Pages Sent ________
From: Name
Company
Address
City / State / ZIP / Country
Telephone: (_______) _________ - _________
FAX: (______) _________ - _________
Application (optional):
Would you like a reply?
Y
N
Device: 24LCS21
Literature Number: DS21127G
Questions:
1. What are the best features of this document?
2. How does this document meet your hardware and software development needs?
3. Do you find the organization of this document easy to follow? If not, why?
4. What additions to the document do you think would enhance the structure and subject?
5. What deletions from the document could be made without affecting the overall usefulness?
6. Is there any incorrect or misleading information (what and where)?
7. How would you improve this document?
DS21127G-page 20
 1995-2012 Microchip Technology Inc.
24LCS21
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO.
X
/XX
XXX
Device
Temperature
Range
Package
Pattern
Device:
24LCS21: Dual Mode I2C Serial EEPROM
24LCS21T: Dual Mode I2C Serial EEPROM (Tape and Reel)
Temperature
Range:
Blank
I
=
0C to
= -40C to
Package:
P
SN
=
=
.
+70C
+85C
Plastic DIP (300 mil Body), 8-lead
Plastic SOIC (150 mil Body), 8-lead
Sales and Support
Data Sheets
Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and
recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following:
1.
2.
Your local Microchip sales office
The Microchip Worldwide Site (www.microchip.com)
Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using.
New Customer Notification System
Register on our web site (www.microchip.com/cn) to receive the most current information on our products.
 1995-2012 Microchip Technology Inc.
DS21127G-page 21
24LCS21
NOTES:
DS21127G-page 22
 1995-2012 Microchip Technology Inc.
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.
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.
Trademarks
The Microchip name and logo, the Microchip logo, dsPIC,
FlashFlex, KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro,
PICSTART, PIC32 logo, rfPIC, SST, SST Logo, SuperFlash
and UNI/O are registered trademarks of Microchip Technology
Incorporated in the U.S.A. and other countries.
FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor,
MTP, SEEVAL and The Embedded Control Solutions
Company are registered trademarks of Microchip Technology
Incorporated in the U.S.A.
Silicon Storage Technology is a registered trademark of
Microchip Technology Inc. in other countries.
Analog-for-the-Digital Age, Application Maestro, BodyCom,
chipKIT, chipKIT logo, CodeGuard, dsPICDEM,
dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,
ECONOMONITOR, FanSense, HI-TIDE, In-Circuit Serial
Programming, ICSP, Mindi, MiWi, MPASM, MPF, MPLAB
Certified logo, MPLIB, MPLINK, mTouch, Omniscient Code
Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit,
PICtail, REAL ICE, rfLAB, Select Mode, SQI, Serial Quad I/O,
Total Endurance, TSHARC, UniWinDriver, WiperLock, ZENA
and Z-Scale 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.
GestIC and ULPP are registered trademarks 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.
© 1995-2012, Microchip Technology Incorporated, Printed in
the U.S.A., All Rights Reserved.
Printed on recycled paper.
ISBN: 9781620767313
QUALITY MANAGEMENT SYSTEM
CERTIFIED BY DNV
== ISO/TS 16949 ==
 1995-2012 Microchip Technology Inc.
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.
DS21127G-page 23
Worldwide Sales and Service
AMERICAS
ASIA/PACIFIC
ASIA/PACIFIC
EUROPE
Corporate Office
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7200
Fax: 480-792-7277
Technical Support:
http://www.microchip.com/
support
Web Address:
www.microchip.com
Asia Pacific Office
Suites 3707-14, 37th Floor
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Tel: 86-10-8569-7000
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Tel: 86-28-8665-5511
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Tel: 86-23-8980-9588
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Tel: 31-416-690399
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Tel: 82-53-744-4301
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Tel: 60-4-227-8870
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Tel: 63-2-634-9065
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Tel: 65-6334-8870
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China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
Taiwan - Hsin Chu
Tel: 886-3-5778-366
Fax: 886-3-5770-955
China - Shenzhen
Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
Taiwan - Kaohsiung
Tel: 886-7-213-7828
Fax: 886-7-330-9305
China - Wuhan
Tel: 86-27-5980-5300
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Taiwan - Taipei
Tel: 886-2-2508-8600
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China - Xian
Tel: 86-29-8833-7252
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Thailand - Bangkok
Tel: 66-2-694-1351
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UK - Wokingham
Tel: 44-118-921-5869
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Tel: 86-592-2388138
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Tel: 86-756-3210040
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DS21127G-page 24
Italy - Milan
Tel: 39-0331-742611
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10/26/12
 1995-2012 Microchip Technology Inc.