© 2008 Microchip Technology Inc. DS21227F-page 1
25AA320/25LC320/25C320
Device Selection Table
Features:
Low-Power CMOS Technology:
- Write current: 3 mA maximum
- Read current: 500 μA, typical
- S tandb y current: 500 nA, typical
4096 x 8 Bit Organization
32 Byte Page
Write Cycle Time: 5 ms Maximum
Self-Timed Erase and Write Cycles
Block Write Protection:
- Protect none, 1/4, 1/2 or all of array
Built -in W ri te Protec tio n:
- Power on/off data protection circuitry
- Write enable latch
- Write-protect pin
Seque nti al Read
High Reliability:
- Endurance: 1M E/W cycles
- Data retention: > 200 years
- ESD protection: > 4000V
8-Pin PDIP, SOIC and TSSOP Packages
14-Lead TSSOP Packa ge
Temperature Ranges Supported:
Description:
The Microchip Technology Inc. 25AA320/25LC320/
25C320 (25XX320*) are 32 Kbit serial Electrically
Erasable PROMs. The memory is accessed via a
simple Serial Peripheral Interface (SPI) compatible
serial bus. The bus signals required are a clock input
(SCK) plus separate data in (SI) and data out (SO)
lines. Ac cess to the dev ice is contro lled th rough a C hip
Select (CS) input.
Communication to the device can be paused via the
hold pin (HOLD). While the device is paused,
transitions on its inputs will be ignored, with the
exception of Chip Select, allowing the host to service
higher priority interrupts.
Block Diagram
Package Types
Part
Number VCC
Range Max. Clock
Frequency Temp.
Ranges
25AA320 1.8-5.5V 1 MHz I
25LC320 2.5-5.5V 2 MHz I,E
25C320 4.5-5.5V 3 MHz I,E
- Industrial (I): -40°Cto +85°C
- Automotive (E): -40°C to +125°C
SI
SO
SCK
CS
HOLD
WP
STATUS
Register
I/O Control Memory
Control
Logic
HV Generator
EEPROM
Array
Page
Y Decoder
Sense Amp.
R/W Control
Logic
VCC
VSS
Latches
XDEC
TSSOP
PDIP, SOIC TSSOP
CS
SO
WP
VSS
VCC
HOLD
SCK
SI
1
2
3
4
8
7
6
5
25XX320
HOLD
VCC
CS
SO
1
2
3
4
8
7
6
5
SCK
SI
VSS
WP
25XX320
NC
CS
SO
NC
WP
VSS
NC
NC
VCC
HOLD
NC
SCK
SI
NC
25XX320
1
2
3
4
14
13
12
11
510
9
78
6
32K SPI Bus Serial EEPROM
*25XX320 is used in this document as a generic part number for the 25AA320/25LC320/25C320 devices.
Not recommended for new designs –
Please use 25AA320A or 25LC320A.
25AA320/25LC320/25C320
DS21227F-page 2 © 2008 Microchip Technology Inc.
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 under bias...............................................................................................................-40°C to 125°C
ESD protection on all pins..........................................................................................................................................4 kV
TABLE 1-1: DC CHARACTERISTICS
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device . This i s a stres s ratin g only and functio nal operati on of the devic e at thos e or any other co nditio ns abov e thos e
indicated in the operational listings of this specification is not implied. Exposure to maximum rating conditions for an
extended period of time may affect device reliability.
DC CHARACTERISTICS Industrial (I): TA = -40°C to +85°C VCC = 1.8V to 5.5V
Automotive (E):TA = -40°C to +125°C VCC = 2.5V to 5.5V
Param.
No. Sym. Characteristics Min. Max. Units Conditions
D1 VIH1High-level input
voltage 2.0 VCC+1 V VCC2.7V (Note)
D2 VIH20.7 VCC VCC+1 V VCC< 2.7V (Note)
D3 VIL1Low-level input
voltage -0.3 0.8 V VCC2.7V (Note)
D4 VIL2-0.3 0.3 VCC VVCC < 2.7V (Note)
D5 VOL Low-level output
voltage —0.2VIOL = 1.0 mA, VCC < 2.5V
D6 VOH High-level output
voltage VCC -0.5 V IOH = -400 μA
D7 ILI Input leakage current ±1 μACS = VCC, VIN = VSS TO VCC
D8 ILO Output lea kage
current —±1μACS = VCC, VOUT = VSS TO VCC
D9 CINT Intern al Cap acit ance
(all inputs and
outputs)
—7pFT
A = 25°C, CLK = 1.0 MHz,
VCC = 5.0V (Note)
D10 ICC Read Operating Current
1
500 mA
μAVCC = 5.5V; FCLK = 3.0 MHz;
SO = Open
VCC = 2.5V; FCLK = 2.0 MHz;
SO = Open
D11 ICC Write
5
3mA
mA VCC = 5.5V
VCC = 2.5V
D12 ICCS Standby Current
5
1μA
μACS = VCC = 5.5V, Inputs tied to VCC or
VSS
CS = VCC = 2.5V, Inputs tied to VCC or
VSS
Note: This parameter is periodically sampled and not 100% tested.
© 2008 Microchip Technology Inc. DS21227F-page 3
25AA320/25LC320/25C320
TABLE 1-2: AC CHARACTERISTICS
AC CHARACTERISTICS Industrial (I): TA = -40°C to +85°C VCC = 1.8V to 5.5V
Automotive (E): TA = -40°C to +125°C VCC = 2.5V to 5.5V
Param.
No. Sym. Characteristic Min. Max. Units Conditions
1F
CLK Clock Frequency
3
2
1
MHz
MHz
MHz
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
2T
CSS CS Setup Time 100
250
500
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
3T
CSH CS Hold Time 150
250
475
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
4T
CSD CS Disable Time 500 ns
5T
SU Data Setup Time 30
50
50
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
6T
HD Data Hold T ime 50
100
100
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
7T
RCLK Rise Time 2 μs(Note 1)
8T
FCLK Fall Time 2 μs(Note 1)
9T
HI Clock High Time 150
230
475
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
10 TLO Clock Low Time 150
230
475
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
11 TCLD Clock Delay Time 50 ns
12 TCLE Clock Enable Time 50 ns
13 TVOutput Valid from
Clock Low
150
230
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
14 THO Output Hold Time 0 ns (Note 1)
15 TDIS Output Disable Time
200
250
ns
ns
ns
VCC = 4.5V to 5.5V (Note 1)
VCC = 2.5V to 5.5V (Note 1)
VCC = 1.8V to 5.5V
16 THS HOLD Setup T ime 100
100
200
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
17 THH HOLD Hold Time 100
100
200
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
18 THZ HOLD Low to Output
High-Z 100
150
200
ns
ns
ns
VCC = 4.5V to 5.5V (Note 1)
VCC = 2.5V to 5.5V (Note 1)
VCC = 1.8V to 5.5V
19 THV HOLD High to Output
Valid 100
150
200
ns
ns
ns
VCC = 4.5V to 5.5V
VCC = 2.5V to 5.5V
VCC = 1.8V to 5.5V
20 TWC Internal Write Cycle
Time —5ms
21 Endur ance 1M E/W
Cycles (Note 2)
Note 1: This parameter is periodically sampled and not 100% tested.
2: This parameter is not tested but established 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.
25AA320/25LC320/25C320
DS21227F-page 4 © 2008 Microchip Technology Inc.
FIGURE 1-1: HOLD TIMING
FIGURE 1-2: SERIAL INPUT TIMING
FIGURE 1-3: SERIAL OUTPUT TI MING
CS
SCK
SO
SI
HOLD
17
16 16 17
1918
Don’t Care 5
High-Impedance
n + 2 n + 1 n n - 1
n
n + 2 n + 1 n nn - 1
CS
SCK
SI
SO
65
8
711
3
LSB in
MSB in
High-Impedance
12
Mode 1,1
Mode 0,0
4
2
CS
SCK
SO
10
9
13
MSB out ISB out
3
15
Don’t Care
SI
Mode 1,1
Mode 0,0
14
© 2008 Microchip Technology Inc. DS21227F-page 5
25AA320/25LC320/25C320
TABLE 1-3: AC TEST CONDITIONS FIGURE 1-4: AC TEST CIRCUIT
AC Waveform:
VLO = 0.2V
VHI = VCC - 0.2V (Note 1)
VHI = 4.0V (Note 2)
Timing Measurement Refere nce Lev el
Input 0.5 VCC
Output 0.5 VCC
Note 1: For VCC 4.0V
2: For VCC > 4.0V
VCC
SO
100 pF
1.8 KΩ
2.25 KΩ
25AA320/25LC320/25C320
DS21227F-page 6 © 2008 Microchip Technology Inc.
2.0 PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 2-1.
TABLE 2-1: PIN FUNCTION TABLE
2.1 Chip Select (CS)
A low level on this pin selects the device. A high level
deselects the device and forces it into Standby mode.
However, a programming cycle which is already
initiated or in p r ogre ss w il l be co mpl ete d, regardle ss of
the CS input signal. If CS is brought high during a
progra m cycle, t he device wil l go into Standb y mode as
soon as the programming cycle is complete. When the
device is deselected, SO goes to the high-impedance
state, allowing multiple parts to share the same SPI
bus. A low-to-high transition on CS after a valid write
sequence initiates an internal write cycle. After power-
up, a low lev el on CS is required p r ior to any se qu enc e
being initiated.
2.2 Serial Output (SO)
The SO pin is used to transfer data out of the 25XX320.
During a read cy cl e, data is sh if ted out on this pin after
the falling edge of the serial clock.
2.3 Write-Protect (WP)
This pin is used in conjunction with the WPEN bit in the
STATUS register to prohibit writes to the nonvolatile
bits in the STATUS register. When WP is low and
WPEN is high, w riting to the nonvolat ile bits in the STA-
TUS register is disabled. All other operations function
normally. When WP is high, all functions, including
writes to the nonvolatile bits in the STATUS register
operate no rmally. If the WPEN bit is set, WP low during
a STATUS register write sequence will disable writing
to the STATUS register. If an internal write cycle has
already begun, WP go ing low w ill h ave no ef fect on the
write.
The WP pin function is blocked when the WPEN bit in
the STATUS register is low. This allows the user to
install the 25XX320 in a system with WP pin grounded
and still be able to write to the STATUS register. The
WP pin functi ons will be enabl ed when the WPEN bit is
set high.
2.4 Serial Input (SI)
The SI pin is used to transfer data into the device. It
receives instructions, addresses, and data. Data is
latched on the rising edge of the serial clock.
2.5 Serial Clock (SCK)
The SCK is used to synchronize the communication
between a master and the 25XX320. Instructions,
addresses, or data present on the SI pin are latched on
the risin g e dge of the c lo ck in put, while dat a on t he SO
pin is updated after the falling edge of the clock input.
2.6 Hold (HOLD)
The HOLD pin is used to suspend transmission to the
25XX320 w hile in the middle of a seri al sequ ence wit h-
out having to re-transmit the entire sequence again. It
must be held high any time this function is not being
used. Once the device is selected and a serial
sequence is underway, the HOLD pin may be pulled
low to pause further serial communication without
resetting the serial sequence. The HOLD pin must be
brought low while SCK is low, otherwise the HOLD
function will not be invoked until the next SCK high-to-
low tr ansition. The 25XX3 20 must remain selected dur-
ing this sequence. The SI, SCK, and SO pins are in a
high-impedance state during the time the device is
paus ed and tran sitions on these p ins will be ignored. To
resume serial communication, HOLD must be brought
high while the SCK pin is low, otherwise serial
communication will not resume. Lowering the HOLD
line at any time will tri-state the SO line.
Name PDIP SOIC 8-pin
TSSOP 14-lead
TSSOP Description
CS 1 1 3 1 Chip Select Input
SO 2 2 4 2 Serial Data Output
NC 3,4,5 Not Connected
WP 3 3 5 6 Write-Protect Pin
Vss 4 4 6 7 Ground
SI 5 5 7 8 Serial Data Input
SCK 6 6 8 9 Serial Clock Input
NC 10,11,12 Not Connected
HOLD 7 7 1 13 Hold Input
Vcc 8 8 2 14 Supply Voltage
© 2008 Microchip Technology Inc. DS21227F-page 7
25AA320/25LC320/25C320
3.0 FUNCTIONAL DESCRIPTION
3.1 Principles Of Operation
The 25XX320 are 4096 byte Serial EEPROMs
design ed to interf ace di rec tly w ith the Seri al P erip heral
Interface (SPI) port of many of today’s popular
microcontroller families, including Microchip’s
PIC16C6X/7X microcontrollers. It may also interface
with mic rocontrollers that do not ha ve a built-in SPI port
by using discrete I/O lines programmed properly with
the software.
The 25XX32 0 contain s an 8-bit instr uction regist er . The
device is accessed via the SI pin, with data being
clocked in on the ris ing edg e of SCK. Th e C S pin mus t
be low and the HOLD pin must be high for the entire
operation.
Table 3-1 contains a list of the possible instruction
bytes and format for device operation. All instructions,
addresses and data are transferred MSB first, LSB last.
Dat a is sampled on the firs t rising edg e of SCK afte r CS
goes low. If the clock line is shared with other
periphe ral de vices on the SPI bus, the user can assert
the HOLD input and place the 25XX320 in ‘HOLD’
mode. After releasing the HOLD pin, operation will
resume from the point when the HOLD was asserted.
3.2 Read Sequence
The device is selected by pulling CS low. The 8-bit
READ instruction is transmitted to the 25XX320 fol-
lowe d by the 16 - b it ad dr e s s, wi t h the fo ur MS Bs of t he
address being “don’t care” bits. After the correct READ
instruc tio n a nd address ar e s en t, t he dat a store d i n th e
memory at the selected address is shifted out on the
SO pin. The data stored in the memory at the next
address can be read sequentially by continuing to pro-
vide cl ock puls es. The inter nal Addr ess Pointe r is auto-
matically incremented to the next higher address after
each byte of data is shifted out. When the highest
address is reached (0FFFh), the address counter rolls
over to address 0000h allowing the read cycle to be
continu ed indefi nitely. The read op eration is terminate d
by raising the CS pin (Figure 3-1).
3.3 Write Sequence
Prior to any attempt to write data to the 25XX320, the
write enable latch must be set by issuing the WREN
instruction (Figure 3-4). This is done by setting CS low
and then clocking out the proper instruction into the
25XX320. After all eight bits of the instruction are
transmitted, the CS must be brought high to set the
write enable latch. If the write operation is initiated
immediately after the WREN instruction without CS
being brought high, the data will not be written to the
array bec ause the w rite enable l atch will not h ave been
properly set.
Once the write enable latch is set, the user may
proceed by setting the CS low, issuing a WRITE
instruc tion, followe d by the 16-b it address, with the four
MSBs of the address being “don’t care” bits, and then
the data to be written. Up to 32 bytes of data can be
sent to the 25XX320 before a write cycle is necessary.
The only restriction is that all of the bytes must reside
in the same page. A page address begins with xxxx
xxxx xxx0 0000 and ends with xxxx xxxx xxx1
1111. If the internal address counter reaches xxxx
xxxx xxx1 1111 and the clock continues, the counter
will roll back to the first address of the page and over-
write any data in the page that may have been written.
For the data to be actually written to the array, the CS
must be brought high a fter the Leas t Significant bit (D0)
of the nth data byte has been clocked in. If CS is
brought high at any other time, the write operation will
not be completed. Refer to Figure 3-2 and Figure 3-3
for more detailed illustrations on the byte write
sequence and the page write sequence, respectively.
While the write is in pro gress, the ST ATUS register may
be read to check the status of the WPEN, WIP, WEL,
BP1 and BP0 bits (Figure 3-6). A read attempt of a
memory array location will not be possible during a
write cycle. When the write cycle is completed, the
write enab le latc h is res et.
TABLE 3-1: INSTRUCTION SET
Instruction Name Instruction Format Description
READ 0000 0011 Read data from memory array beginning at selected address
WRITE 0000 0010 Write data to memory array beginning at selected address
WRDI 0000 0100 Reset the write enable latch (disable write operations)
WREN 0000 0110 Set the write enable latch (enable write operations)
RDSR 0000 0101 Read STATUS register
WRSR 0000 0001 Wri te STATUS register
25AA320/25LC320/25C320
DS21227F-page 8 © 2008 Microchip Technology Inc.
FIGURE 3-1: READ SEQUENCE
FIGURE 3-2: BYTE WRITE SEQUENCE
FIGURE 3-3: PAGE WRITE SEQUENCE
SO
SI
SCK
CS
0 234567891011 21222324252627282930311
0100000115 14 13 12 210
76543210
Instruction 16-bi t Addr ess
Data Out
High-Impedance
SO
SI
CS
91011 2122232425262728293031
0000000115 14 13 12 21076543210
Instruction 16-bit Address Data Byte
High-Impedance
SCK 0 23456718 Twc
SI
CS
9 1011 2122232425262728293031
0000000115 14 13 12 21076543210
Instructi on 16-bit Addre ss Data Byte 1
SCK 0 23456718
SI
CS
41 42 43 46 47
76543210
Data Byte n (32 max)
SCK 32 34 35 36 37 38 3933 40
76543210
Data Byte 3
76543210
Data Byte 2
44 45
© 2008 Microchip Technology Inc. DS21227F-page 9
25AA320/25LC320/25C320
3.4 Wr ite Enable (WREN) and Write
Disable (WRDI)
The 25XX320 contains a write enable latch. See
Table 3-3 for the Write-Protect Functionality Matrix.
This latch must be set before any write operation will be
completed internally. The WREN instruction will set the
latch, and the WRDI will reset the latch.
The following is a list of conditions under which the
write enab le latc h wi ll be reset:
Power-up
WRDI instruction successfully executed
WRSR instruction successfully executed
WRITE instruction successfully executed
FIGURE 3-4: WRITE ENABLE SEQUENCE
FIGURE 3-5: WRITE DISABLE SEQUENCE
SCK
0 2345671
SI
High-Impedance
SO
CS
010000 01
SCK
0 2345671
SI
High-Impedance
SO
CS
010000 01
0
25AA320/25LC320/25C320
DS21227F-page 10 © 2008 Microchip Technology Inc.
3.5 Read Status Register Instruction
(RDSR)
The Read Status Register instruction (RDSR) provi des
access to the STATUS register. The STATUS register
may be rea d at any time, ev en during a write cy cle. The
STATUS register is formatted as follows:
The Write-In-Process (WIP) bit indicates whether the
25XX320 is busy with a write operation. When set to a
1’, a write is in progress; when set to a ‘0’, no write is
in progress. This bit is read-only.
The Write Enable Lat ch (WEL) bit indicat es the st atus
of the write enable latch. When set to a1’, the latch
allows writes to the array, when set to a ‘0’, the latch
prohibits writes to the array. The state of this bit can
always be up dated vi a the WREN or WR DI comma nds
regardless of the state of write protection on the STA-
TUS register. This bit is read-only.
The Block Protection (BP0 and BP1) bits indicate
which blocks are currently write-protected. These bits
are set by th e us er i ssui ng the WRSR in structi on . These
bits are nonvolatile.
See Figure 3-6 for the RDSR timing sequence.
FIGURE 3-6: READ STATUS REGISTER TIMING SEQUENCE
76543 2 1 0
WPEN X X X BP1 BP0 WEL WIP
SO
SI
CS
9101112131415
11000000
7654 210
Instruction
Data from STATUS R e gister
High-Impedance
SCK
0 23456718
3
© 2008 Microchip Technology Inc. DS21227F-page 11
25AA320/25LC320/25C320
3.6 Wr ite Status Register Inst ruction
(WRSR)
The W rite S t atus Register inst ruction (WRSR) allows the
user to select one of four levels of protection for the
array by writing to the appropriate bits in the STATUS
register. The array is divided up into four segments.
The user ha s the abili ty to write-p rotect none , one, two,
or all fo ur of the se gment s of th e array. The partitio ning
is controlled as shown in Table 3-2.
The Write-Protect Enable (WPEN) bit is a nonvolatile
bit that is availabl e as an enab le bit for the WP pi n. The
Write-Protect (WP) pin and the Write-Protect Enable
(WPEN) bit in the STATUS register control the pro-
grammable hardware write-protect feature. Hardware
write p r ote cti on is en abl ed w hen WP pin is lo w an d th e
WPEN bit is high. Hardware write protec tion is disable d
when either the WP pin is high or the WPEN bit is low.
When the chip is hardware write-protected, only writes
to nonvolatile bits i n th e STATUS regist er are di sab le d.
See Table 3-3 for a matrix of functionalit y on the WPEN
bit.
See Figure 3-7 for the WRSR timing sequence.
TABLE 3-2: ARRAY PROTECTION
FIGURE 3-7: WRITE STATUS REGISTER TIMING SEQUENCE
BP1 BP0 Array Addresses
Write-Protected
00 none
01 upper 1/4
(0C00h-0FFFh)
10 upper 1/2
(0800h-0FFFh)
11 all
(0000h-0FFFh)
SO
SI
CS
9101112131415
01000000
7654 210
Instruction Data to STATUS Register
High-Impedance
SCK
0 23456718
3
25AA320/25LC320/25C320
DS21227F-page 12 © 2008 Microchip Technology Inc.
3.7 Data Protection
The following protection has been implemented to
prevent i nadvertent wr ites to the array:
The write enable latch is reset on power-up
•A WRITE ENABLE instru ction must be i s sued to
set the write ena ble latch
After a byte write, page write or STATUS register
write, the write enable latch is reset
•CS
must be set high after the proper number of
clock cycles to start an internal write cycle
Access t o the a rray during an intern al write c ycle
is ignored and programming is continued
3.8 Power-On State
The 25XX320 powers on in the following state:
The device is in low-power Standby mode
(CS=1)
The write enable latch is reset
SO is in high-impedance state
A low level on CS is required to enter active state
.
TABLE 3-3: WRITE-PROTECT FUNCTIONALITY MATRIX
WPEN WP WEL Protected Blocks Unprotected Blocks STATUS Register
xx0Protected Protected Protected
0x1Protected Writable Writable
1Low 1Protected Writable Protected
xHigh 1Protected Writable Writable
© 2008 Microchip Technology Inc. DS21227F-page 13
25AA320/25LC320/25C320
4.0 PACKAGING INFORMATION
4.1 Package Marking Information
XXXXXXXX
XXXXXNNN
YYWW
8-Lead PDIP (300 mil) Example:
14-Lead T SSOP Example:
8-Lead SOIC (150 mil) Example:
XXXXXXXX
XXXXYYWW
NNN
XXXXXXXX
NNN
25LC320
/PNNN
YYWW
25LC320
I/SN YYWW
NNN
25L32
YYWW
NNN
8-Lead TSSOP Example:
XXXX
XYWW
NNN
5LBX
IYWW
NNN
YYWW
*Standard marking consists of Microchip part number, year code, week code, and traceability code. For
device markings beyond this, certain price adders apply. Please check with your Microchip Sales Office.
For QTP devices, any special marking adders are included in QTP price.
Legend: XX...X Customer-specific information
Y Year code (last digit of calendar year)
YY Year code (last 2 digits of calendar year)
WW Week code (week of January 1 is week ‘01’)
NNN Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
*This package is P b-free. The Pb-free JEDEC designator ( )
can be found on the outer packaging for this package.
Note: In the even t the full M icroc hip p art numb er cann ot be mark ed on one line, it wil l
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
3
e
3
e
3
e
25AA320/25LC320/25C320
DS21227F-page 14 © 2008 Microchip Technology Inc.


  !"#$%&"' ()"&'"!&)&#*&&&#
 +%&,&!&
- '!!#.#&"#'#%!&"!!#%!&"!!!&$#/!#
 '!#&.0
1,21!'!&$& "!**&"&&!
 3&'!&"&4#*!(!!&4%&&#&
&&255***''54
6&! 7,8.
'!9'&! 7 7: ;
7"')%! 7 <
& 1,
&& = = 
##44!!   - 
1!&&   = =
"#&"#>#& .  - -
##4>#& .   <
: 9& -< -? 
&& 9  - 
9#4!! <  
69#>#& )  ? 
9*9#>#& )  < 
: *+ 1 = = -
N
E1
NOTE 1
D
12
3
A
A1
A2
L
b1
b
e
E
eB
c
  * ,<1
© 2008 Microchip Technology Inc. DS21227F-page 15
25AA320/25LC320/25C320
 ! ""#$%& !'

  !"#$%&"' ()"&'"!&)&#*&&&#
 +%&,&!&
- '!!#.#&"#'#%!&"!!#%!&"!!!&$#''!#
 '!#&.0
1,2 1!'!&$& "!**&"&&!
.32 %'!("!"*&"&&(%%'&"!!
 3&'!&"&4#*!(!!&4%&&#&
&&255***''54
6&! 99..
'!9'&! 7 7: ;
7"')%! 7 <
& 1,
: 8& = = 
##44!!   = =
&#%%+  = 
: >#& . ?1,
##4>#& . -1,
: 9& 1,
,'%@&A  = 
3&9& 9  = 
3&& 9 .3
3& IB = <B
9#4!!  = 
9#>#& ) - = 
#%& DB = B
#%&1&&' EB = B
D
N
e
E
E1
NOTE 1
12 3
b
A
A1
A2
L
L1
c
h
h
φ
β
α
  * ,1
25AA320/25LC320/25C320
DS21227F-page 16 © 2008 Microchip Technology Inc.
 ! ""#$%& !'
 3&'!&"&4#*!(!!&4%&&#&
&&255***''54
© 2008 Microchip Technology Inc. DS21227F-page 17
25AA320/25LC320/25C320
() )"* ! (+%+( !

  !"#$%&"' ()"&'"!&)&#*&&&#
 '!!#.#&"#'#%!&"!!#%!&"!!!&$#''!#
- '!#&.0
1,2 1!'!&$& "!**&"&&!
.32 %'!("!"*&"&&(%%'&"!!
 3&'!&"&4#*!(!!&4%&&#&
&&255***''54
6&! 99..
'!9'&! 7 7: ;
7"')%! 7 <
& ?1,
: 8& = = 
##44!!  <  
&#%%   = 
: >#& . ?1,
##4>#& . -  
##49&  - -
3&9& 9  ? 
3&& 9 .3
3& IB = <B
9#4!!  = 
9#>#& )  = -
D
N
E
E1
NOTE 1
12
b
e
c
A
A1
A2
L1 L
φ
  * ,<?1
25AA320/25LC320/25C320
DS21227F-page 18 © 2008 Microchip Technology Inc.
,+() )"* ! (+%+( !

  !"#$%&"' ()"&'"!&)&#*&&&#
 '!!#.#&"#'#%!&"!!#%!&"!!!&$#''!#
- '!#&.0
1,2 1!'!&$& "!**&"&&!
.32 %'!("!"*&"&&(%%'&"!!
 3&'!&"&4#*!(!!&4%&&#&
&&255***''54
6&! 99..
'!9'&! 7 7: ;
7"')%! 7 
& ?1,
: 8& = = 
##44!!  <  
&#%%   = 
: >#& . ?1,
##4>#& . -  
##49&   
3&9& 9  ? 
3&& 9 .3
3& B = <B
9#4!!  = 
9#>#& )  = -
NOTE 1
D
N
E
E1
12
e
b
c
A
A1
A2
L1 L
φ
  * ,<1
© 2008 Microchip Technology Inc. DS21227F-page 19
25AA320/25LC320/25C320
APPENDIX A: REVISION HISTORY
Revision D
Corrections to Section 1.0, Electrical Characteristics.
Revision E
Revise Endurance from 100K to 1M.
Revision F (June 2008)
Added “Not Reco mmended” note; Upda ted Packaging;
General updates.
25AA320/25LC320/25C320
DS21227F-page 20 © 2008 Microchip Technology Inc.
NOTES:
© 2008 Microchip Technology Inc. DS21227F-page 21
25AA320/25LC320/25C320
THE MICROCHIP WEB SITE
Microc hip pro vides onl ine s upport v ia our W WW site at
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Technical s upport is a vailable through the web si te
at: http://support.microchip.com
25AA320/25LC320/25C320
DS21227F-page 22 © 2008 Microchip Technology Inc.
READER RESP ONSE
It is ou r intentio n to provide you w it h th e b es t do cument ation po ss ib le to ensure suc c es sfu l u se of y ou r M ic roc hip prod-
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DS21227F25AA320/25LC320/25C320
1. What are the best fe atures of this document?
2. How does this document meet your hardware and software development needs?
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4. What additions to the document do you think would enhance the structure and subject?
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7. How would you improve this document?
© 2008 Microchip Technology Inc. DS21227F-page 23
25AA320/25LC320/25C320
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
PatternPackageTemperature
Range
Device
Device: 25AA320: 32 Kbit 1.8V SP I Serial EEPROM
25AA320T: 32 Kbit 1.8V SPI Serial EEPROM
(Tape and Reel)
25AA320X 32-bit 1.8V SPI Serial EEPROM
in alternate pinout (ST only)
25AA320XT 32-bit 1.8V SPI Serial EEPROM
in alternate pinout Tape and Reel
(ST only)
25LC320: 32 Kbit 2.5V SPI Serial EEPROM
25LC320T: 32 Kbit 2.5V SPI Serial EEPROM
(Tape and Reel)
25LC320X 32-bit 2.5V SPI Serial EEPROM
in alternate pinout (ST only)
25LC320XT 32-bit 2.5V SPI Serial EEPRO M
in alternate pinout Tape and Reel
(ST only)
25C320: 32 Kbit 5V SPI Serial EEPRO M
25C320T: 32 Kbit 5V SPI Serial EEPROM
(Tape and Reel)
25C320X 32-bit 5V SPI Serial EEPROM
in alternate pinout (ST only)
25C320XT 32-bit 5V SPI Serial EEPROM
in alternate pinout Tape and Reel
(ST only)
Temperature
Range: I= -40°C to +85°C
E= -40°C to +1 2 5 °C
Package: P = Plastic DIP (300 mil body), 8-lead
SN = Plastic SOIC (150 mil body),
8-lead
ST = Plastic TSSOP (4.4 mm body),
8-lead
ST14 = Plastic TSSOP (4.4 mm body),
14-lead
Examples:
a) 25LC320-I/SN: Industrial Temp.,
SOIC package
b) 25LC320T-I/SN: Tape and Reel,
Industrial Temp., SOIC package
c) 25LC320-E/SN: Extended Tem p.,
SOIC package
d) 25C320-I/SN: Industrial Tem p.,
SOIC package
e) 25C320T-I/SN: Tape and Reel,
Industrial Temp., SOIC package
f) 25C320-I/ST: Industrial Temp.,
TSSOP package
g) 25C320-E/SN: Extended Temp.,
SOIC package
25AA320/25LC320/25C320
DS21227F-page 24 © 2008 Microchip Technology Inc.
NOTES:
© 2008 Microchip Technology Inc. DS21227F-page 25
Information contained in this publication regarding device
applications a nd the lik e is provided only f or your convenien ce
and may be supers ed ed by u pdates. I t is y our responsibil it y 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, Accuron,
dsPIC, KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro,
PICST ART, PRO MA TE, rfPIC and SmartShunt are registered
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
FilterLab, Linear Active Thermistor, MXDEV, MXLAB,
SEEV AL, SmartSensor and The Embedded Control Solutions
Company are registered trademarks of Microchip Technology
Incorporated in the U.S.A.
Analog-for-the-Digital Age, Application Maestro, CodeGuard,
dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,
ECONOMONITOR, FanSense, In-Circuit Serial
Prog ra m ming , ICSP, IC E P I C , M i nd i , MiWi, MPASM , MPLAB
Certified logo, MPLIB, MPLINK, mTouch, PICkit, PICDEM,
PICDEM.net, PICtail , PIC32 logo, PowerCal, PowerInfo,
PowerMate, PowerTool, REAL ICE, rfLAB, Select Mode, Total
Endurance, UNI/O, WiperLock and ZENA are trademarks of
Microchip Technology I ncorporat ed in the U.S.A. and other
countries.
SQTP is a service mark of Microchip T echnology Incorporated
in the U.S.A.
All other trademarks mentioned herein are property of their
respective companies.
© 2008, Microchip Technology Incorporated, Pr inted in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
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 t he
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 c onstantly evolving. We a t Microc hip are co m mitted to continuously improving the code prot ect ion featur es of our
products. Attempts to break Microchip’ s code protection feature may be a violation of the Digital Millennium Copyright Act. If such act s
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Microchip received ISO/TS-16949:2002 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, microperiph erals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
DS21227F-page 26 © 2008 Microchip Technology Inc.
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