23A256/23K256
256K SPI Bus Low-Power Serial SRAM
Device Selection Table
Part Number
VCC Range
Page Size
Temp. Ranges
Packages
23K256
2.7-3.6V
32 Byte
I, E
P, SN, ST
23A256
1.5-1.95V
32 Byte
I
P, SN, ST
Features:
Description:
• Max. Clock 20 MHz
• Low-Power CMOS Technology:
- Read Current: 3 mA at 1 MHz
- Standby Current: 4 A Max. at +85°C
• 32,768 x 8-bit Organization
• 32-Byte Page
• HOLD pin
• Flexible Operating modes:
- Byte read and write
- Page mode (32 Byte Page)
- Sequential mode
• Sequential Read/Write
• High Reliability
• Temperature Ranges Supported:
- Industrial (I):
-40C to +85C
-40C to +125C
- Automotive (E):
The Microchip Technology Inc. 23X256 are 256 Kbit
Serial SRAM devices. 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. Access to the device is controlled through a Chip
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.
The 23X256 is available in standard packages
including 8-lead PDIP and SOIC, and advanced
packaging including 8-lead TSSOP.
Package Types (not to scale)
• Pb-Free and RoHS Compliant, Halogen Free
Pin Function Table
Name
Function
CS
Chip Select Input
SO
Serial Data Output
VSS
Ground
SI
Serial Data Input
SCK
Serial Clock Input
HOLD
Hold Input
VCC
Supply Voltage
2008-2011 Microchip Technology Inc.
PDIP/SOIC/TSSOP
(P, SN, ST)
CS
1
8
VCC
SO
2
7
HOLD
NC
3
6
SCK
VSS
4
5
SI
DS22100F-page 1
23A256/23K256
1.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings (†)
VCC .............................................................................................................................................................................4.5V
All inputs and outputs w.r.t. VSS ......................................................................................................... -0.3V to VCC +0.3V
Storage temperature .................................................................................................................................-65°C to 150°C
Ambient temperature under bias ...............................................................................................................-40°C to 125°C
ESD protection on all pins ...........................................................................................................................................2kV
† 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 those or any other conditions above those
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.
TABLE 1-1:
DC CHARACTERISTICS
DC CHARACTERISTICS
Param.
No.
Sym.
Characteristic
Industrial (I):
TA = -40°C to +85°C
Automotive (E): TA = -40°C to +125°C
Min.
Typ(1)
Max.
Units
Test Conditions
D001
VCC
Supply voltage
1.5
—
1.95
V
23A256 (I-Temp)
D001
VCC
Supply voltage
2.7
—
3.6
V
23K256 (I,E-Temp)
D002
VIH
High-level input
voltage
.7 VCC
—
VCC +0.3
V
D003
VIL
Low-level input
voltage
-0.3
—
0.2xVCC
0.15xVCC
V
V
23K256 (E-Temp)
D004
VOL
Low-level output
voltage
—
—
0.2
V
IOL = 1 mA
D005
VOH
High-level output
voltage
VCC -0.5
—
—
V
IOH = -400 A
D006
ILI
Input leakage
current
—
—
±0.5
A
CS = VCC, VIN = VSS OR VCC
D007
ILO
Output leakage
current
—
—
±0.5
A
CS = VCC, VOUT = VSS OR VCC
D008
ICC Read
—
—
—
—
—
—
3
6
10
mA
mA
mA
FCLK = 1 MHz; SO = O
FCLK = 10 MHz; SO = O
FCLK = 20 MHz; SO = O
—
0.2
1
A
—
1
4
A
—
5
10
A
CS = VCC = 1.8V, Inputs tied to VCC
or VSS
CS = VCC = 3.6V, Inputs tied to VCC
or VSS
CS = VCC = 3.6V, Inputs tied to VCC
or VSS @ 125°C
7
pF
—
V
Operating current
D009
ICCS
Standby current
D010
CINT
Input capacitance
D011
VDR
RAM data retention
voltage (2)
Note 1:
2:
—
1.2
VCC = 0V, f = 1 MHz, Ta = 25°C
(Note 1)
This parameter is periodically sampled and not 100% tested. Typical measurements taken at room
temperature (25°C).
This is the limit to which VDD can be lowered without losing RAM data. This parameter is periodically
sampled and not 100% tested.
DS22100F-page 2
2008-2011 Microchip Technology Inc.
23A256/23K256
TABLE 1-2:
AC CHARACTERISTICS
AC CHARACTERISTICS
Param.
Sym.
No.
Characteristic
Industrial (I):
TA = -40°C to +85°C
Automotive (E): TA = -40°C to +125°C
Min.
Max.
Units
Test Conditions
1
FCLK
Clock frequency
—
—
—
—
10
16
16
20
MHz
MHz
MHz
MHz
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
2
TCSS
CS setup time
50
32
32
25
—
—
—
—
ns
ns
ns
ns
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
3
TCSH
CS hold time
50
50
50
50
—
—
—
—
ns
ns
ns
ns
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
4
TCSD
CS disable time
50
32
32
25
—
—
—
—
ns
ns
ns
ns
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
5
Tsu
Data setup time
10
10
10
10
—
—
—
—
ns
ns
ns
ns
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
6
THD
Data hold time
10
10
10
10
—
—
—
—
ns
ns
ns
ns
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
7
TR
CLK rise time
—
2
us
Note 1
8
TF
CLK fall time
—
2
us
Note 1
9
THI
Clock high time
50
32
32
25
—
—
—
—
ns
ns
ns
ns
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
10
TLO
Clock low time
50
32
32
25
—
—
—
—
ns
ns
ns
ns
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
11
TCLD
Clock delay time
50
32
32
25
—
—
—
—
ns
ns
ns
ns
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
12
TV
Output valid from clock low
—
—
—
—
50
32
32
25
ns
ns
ns
ns
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
13
THO
Output hold time
0
—
ns
Note 1
Note 1:
This parameter is periodically sampled and not 100% tested.
2008-2011 Microchip Technology Inc.
DS22100F-page 3
23A256/23K256
TABLE 1-2:
AC CHARACTERISTICS (CONTINUED)
Industrial (I):
TA = -40°C to +85°C
Automotive (E): TA = -40°C to +125°C
AC CHARACTERISTICS
Param.
Sym.
No.
Characteristic
Min.
Max.
Units
—
—
—
—
20
20
20
20
ns
ns
ns
ns
Test Conditions
VCC 1.5V (I-Temp)
VCC 1.8V (I-Temp)
VCC 3.0V (E-Temp)
VCC 3.0V (I-Temp)
14
TDIS
Output disable time
15
THS
HOLD setup time
10
—
ns
—
16
THH
HOLD hold time
10
—
ns
—
17
THZ
HOLD low to output High-Z
10
—
ns
—
18
THV
HOLD high to output valid
—
50
ns
—
Note 1:
This parameter is periodically sampled and not 100% tested.
TABLE 1-3:
AC TEST CONDITIONS
AC Waveform:
Input pulse level
Input rise/fall time
Operating temperature
CL = 100 pF
0.1 VCC to 0.9 VCC
5 ns
-40°C to +125°C
—
Timing Measurement Reference Level:
Input
0.5 VCC
Output
0.5 VCC
DS22100F-page 4
2008-2011 Microchip Technology Inc.
23A256/23K256
FIGURE 1-1:
HOLD TIMING
CS
16
15
16
15
SCK
17
SO
n+2
SI
n+2
n+1
n
17
High-Impedance
n
5
Don’t Care
n+1
n-1
n
n
n-1
HOLD
FIGURE 1-2:
SERIAL INPUT TIMING
4
CS
2
7
8
3
11
SCK
5
SI
6
MSB in
LSB in
High-Impedance
SO
FIGURE 1-3:
SERIAL OUTPUT TIMING
CS
9
3
10
SCK
12
SO
13
MSB out
SI
2008-2011 Microchip Technology Inc.
14
LSB out
Don’t Care
DS22100F-page 5
23A256/23K256
2.0
FUNCTIONAL DESCRIPTION
2.1
Principles of Operation
The 23X256 is a 32,768-byte Serial SRAM designed to
interface directly with the Serial Peripheral Interface
(SPI) port of many of today’s popular microcontroller
families, including Microchip’s PIC® microcontrollers. It
may also interface with microcontrollers that do not
have a built-in SPI port by using discrete I/O lines
programmed properly in firmware to match the SPI
protocol.
The 23X256 contains an 8-bit instruction register. The
device is accessed via the SI pin, with data being
clocked in on the rising edge of SCK. The CS pin must
be low and the HOLD pin must be high for the entire
operation.
Table 2-1 contains a list of the possible instruction
bytes and format for device operation. All instructions,
addresses and data are transferred MSB first, LSB last.
Data (SI) is sampled on the first rising edge of SCK
after CS goes low. If the clock line is shared with other
peripheral devices on the SPI bus, the user can assert
the HOLD input and place the 23X256 in ‘HOLD’ mode.
After releasing the HOLD pin, operation will resume
from the point when the HOLD was asserted.
2.2
Modes of Operation
The 23A256/23K256 has three modes of operation that
are selected by setting bits 7 and 6 in the STATUS
register. The modes of operation are Byte, Page and
Burst.
Byte Operation – is selected when bits 7 and 6 in the
STATUS register are set to 00. In this mode, the read/
write operations are limited to only one byte. The
Command followed by the 16-bit address is clocked into
the device and the data to/from the device is transferred
on the next 8 clocks (Figure 2-1, Figure 2-2).
Page Operation – is selected when bits 7 and 6 in the
STATUS register are set to 10. The 23A256/23K256 has
1024 pages of 32 Bytes. In this mode, the read and write
operations are limited to within the addressed page (the
address is automatically incremented internally). If the
data being read or written reaches the page boundary,
then the internal address counter will increment to the
start of the page (Figure 2-3, Figure 2-4).
2.3
Read Sequence
The device is selected by pulling CS low. The 8-bit
READ instruction is transmitted to the 23X256 followed
by the 16-bit address, with the first MSB of the address
being a “don’t care” bit. After the correct READ
instruction and address are sent, the data stored in the
memory at the selected address is shifted out on the
SO pin.
If operating in Page mode, after the first byte of data is
shifted out, the next memory location on the page can
be read out by continuing to provide clock pulses. This
allows for 32 consecutive address reads. After the
32nd address read the internal address counter wraps
back to the byte 0 address in that page.
If operating in Sequential mode, the data stored in the
memory at the next address can be read sequentially
by continuing to provide clock pulses. The internal
Address Pointer is automatically incremented to the
next higher address after each byte of data is shifted
out. When the highest address is reached (7FFFh),
the address counter rolls over to address 0000h,
allowing the read cycle to be continued indefinitely.
The read operation is terminated by raising the CS pin
(Figure 2-1).
2.4
Write Sequence
Prior to any attempt to write data to the 23X256, the
device must be selected by bringing CS low.
Once the device is selected, the Write command can
be started by issuing a WRITE instruction, followed by
the 16-bit address, with the first MSB of the address
being a “don’t care” bit, and then the data to be written.
A write is terminated by the CS being brought high.
If operating in Page mode, after the initial data byte is
shifted in, additional bytes can be shifted into the
device. The Address Pointer is automatically
incremented. This operation can continue for the entire
page (32 Bytes) before data will start to be overwritten.
If operating in Sequential mode, after the initial data
byte is shifted in, additional bytes can be clocked into
the device. The internal Address Pointer is automatically incremented. When the Address Pointer reaches
the highest address (7FFFh), the address counter rolls
over to (0000h). This allows the operation to continue
indefinitely, however, previous data will be overwritten.
Sequential Operation – is selected when bits 7 and 6
in the STATUS register are set to 01. Sequential operation allows the entire array to be written to and read
from. The internal address counter is automatically
incremented and page boundaries are ignored. When
the internal address counter reaches the end of the
array, the address counter will roll over to 0x0000
(Figure 2-5, Figure 2-6).
DS22100F-page 6
2008-2011 Microchip Technology Inc.
23A256/23K256
TABLE 2-1:
INSTRUCTION SET
Instruction Name
Instruction Format
READ
0000 0011
Read data from memory array beginning at selected address
WRITE
0000 0010
Write data to memory array beginning at selected address
RDSR
0000 0101
Read STATUS register
WRSR
0000 0001
Write STATUS register
FIGURE 2-1:
Description
BYTE READ SEQUENCE
CS
0
1
2
3
4
5
6
7
8
9 10 11
21 22 23 24 25 26 27 28 29 30 31
SCK
Instruction
0
SI
0
0
0
0
16-bit Address
0
1
1 15 14 13 12
2
1
0
Data Out
High-Impedance
7
SO
FIGURE 2-2:
6
5
4
3
2
1
0
BYTE WRITE SEQUENCE
CS
0
1
2
3
4
5
6
7
8
9 10 11
21 22 23 24 25 26 27 28 29 30 31
SCK
Instruction
SI
0
0
0
0
0
16-bit Address
0
1
0 15 14 13 12
Data Byte
2
1
0
7
6
5
4
3
2
1
0
High-Impedance
SO
2008-2011 Microchip Technology Inc.
DS22100F-page 7
23A256/23K256
FIGURE 2-3:
PAGE READ SEQUENCE
CS
0
1
2
0
0
0
3
4
5
6
7
8
9 10 11
21 22 23 24 25 26 27 28 29 30 31
SCK
Instruction
SI
0
0
16-bit Address
0 1
2
1 15 14 13 12
1
0
Page X, Word Y
Page X, Word Y
High Impedance
SO
7
6
5
4
3
2
1
0
CS
32 33 34 35 36 37 38 39
SCK
SI
Page X, Word Y+1
7
SO
6
FIGURE 2-4:
5
4
3
2
1
Page X, Word 31
0
7
6
5
4
3
2
Page X, Word 0
1
0
7
6
5
4
3
2
1
0
PAGE WRITE SEQUENCE
CS
0
1
2
0
0
0
3
4
5
6
7
8
9 10 11
21 22 23 24 25 26 27 28 29 30 31
SCK
Instruction
SI
0
0
Page X, Word Y
16-bit Address
0 1
2
0 15 14 13 12
1
0
7
6
5
4
3
2
1
0
Page X, Word Y
CS
32 33 34 35 36 37 38 39
SCK
Page X, Word Y+1
SI
7
DS22100F-page 8
6
5
4
3
2
1
Page X, Word 31
0
7
6
5
4
3
2
Page X, Word 0
1
0
7
6
5
4
3
2
1
0
2008-2011 Microchip Technology Inc.
23A256/23K256
FIGURE 2-5:
SEQUENTIAL READ SEQUENCE
CS
0
1
2
0
0
0
3
4
5
6
7
8
9 10 11
21 22 23 24 25 26 27 28 29 30 31
SCK
Instruction
SI
0
0
16-bit Address
0 1
1 15 14 13 12
2
1
0
Page X, Word Y
7
SO
6
5
4
3
2
1
0
CS
SCK
SI
Page X, Word 31
SO
7
6
5
4
3
2
Page X+1, Word 0
1
0
7
6
5
4
3
2
1
Page X+1, Word 1
0
7
6
5
4
3
2
1
0
CS
SCK
SI
Page X+1, Word 31
SO
7
6
5
4
3
2
2008-2011 Microchip Technology Inc.
Page X+n, Word 1
1
0
7
6
5
4
3
2
Page X+n, Word 31
1
0
7
6
5
4
3
2
1
0
DS22100F-page 9
23A256/23K256
FIGURE 2-6:
SEQUENTIAL WRITE SEQUENCE
CS
0
1
2
3
4
5
6
7
8
9 10 11
21 22 23 24 25 26 27 28 29 30 31
SCK
Instruction
SI
0
0
0
0
0
16-bit Address
0 1
Data Byte 1
2
0 15 14 13 12
1
0
7
6
5
4
3
2
1
0
CS
32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
SCK
Data Byte 2
SI
7
DS22100F-page 10
6
5
4
3
2
Data Byte 3
1
0
7
6
5
4
3
2
Data Byte n
1
0
7
6
5
4
3
2
1
0
2008-2011 Microchip Technology Inc.
23A256/23K256
2.5
Read Status Register Instruction
(RDSR)
The mode bits indicate the operating mode of the
SRAM. The possible modes of operation are:
0 0 = Byte mode (default operation)
The Read Status Register instruction (RDSR) provides
access to the STATUS register. The STATUS register
may be read at any time. The STATUS register is
formatted as follows:
TABLE 2-2:
1 0 = Page mode
0 1 = Sequential mode
1 1 = Reserved
Write and read commands are shown in Figure 2-7 and
Figure 2-8.
STATUS REGISTER
7
6
5
4
3
2
1
0
W/R
W/R
–
–
–
–
–
W/R
0
0
0
0
0
HOLD
MODE MODE
The HOLD bit enables the Hold pin functionality. It must
be set to a ‘0’ before HOLD pin is brought low for HOLD
function to work properly. Setting HOLD to ‘1’ disables
feature.
W/R = writable/readable.
Bits 1 through 5 are reserved and should always be set
to ‘0’.
See Figure 2-7 for the RDSR timing sequence.
FIGURE 2-7:
READ STATUS REGISTER TIMING SEQUENCE (RDSR)
CS
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
1
0
SCK
Instruction
SI
0
0
0
0
0
High-Impedance
SO
2008-2011 Microchip Technology Inc.
1
0
1
Data from STATUS Register
7
6
5
4
3
2
DS22100F-page 11
23A256/23K256
2.6
Write Status Register Instruction
(WRSR)
The Write Status Register instruction (WRSR) allows the
user to write to the bits in the STATUS register as
shown in Table 2-2. This allows for setting of the Device
operating mode. Several of the bits in the STATUS
register must be cleared to ‘0’. See Figure 2-8 for the
WRSR timing sequence.
FIGURE 2-8:
WRITE STATUS REGISTER TIMING SEQUENCE (WRSR)
CS
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
1
0
SCK
Instruction
SI
0
0
0
0
Data to STATUS Register
0
0
0
1
7
6
5
4
3
2
High-Impedance
SO
2.7
Power-On State
The 23X256 powers on in the following state:
• The device is in low-power Standby mode
(CS = 1)
• A high-to-low-level transition on CS is required to
enter active state
DS22100F-page 12
2008-2011 Microchip Technology Inc.
23A256/23K256
3.0
PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 3-1.
TABLE 3-1:
Name
PIN FUNCTION TABLE
PDIP/SOIC
TSSOP
Function
CS
1
Chip Select Input
SO
2
Serial Data Output
VSS
4
Ground
SI
5
Serial Data Input
SCK
6
Serial Clock Input
HOLD
7
Hold Input
VCC
8
Supply Voltage
3.1
Chip Select (CS)
A low level on this pin selects the device. A high level
deselects the device and forces it into Standby mode.
When the device is deselected, SO goes to the highimpedance state, allowing multiple parts to share the
same SPI bus. After power-up, a low level on CS is
required, prior to any sequence being initiated.
3.2
3.5
Hold (HOLD)
The HOLD pin is used to suspend transmission to the
23X256 while in the middle of a serial sequence without
having to retransmit 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 transition.
The 23X256 must remain selected during this
sequence. The SI, SCK and SO pins are in a highimpedance state during the time the device is paused
and transitions on these pins 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.
Hold functionality is disabled by the STATUS register
bit.
Serial Output (SO)
The SO pin is used to transfer data out of the 23X256.
During a read cycle, data is shifted out on this pin after
the falling edge of the serial clock.
3.3
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.
3.4
Serial Clock (SCK)
The SCK is used to synchronize the communication
between a master and the 23X256. Instructions,
addresses or data present on the SI pin are latched on
the rising edge of the clock input, while data on the SO
pin is updated after the falling edge of the clock input.
2008-2011 Microchip Technology Inc.
DS22100F-page 13
23A256/23K256
4.0
PACKAGING INFORMATION
4.1
Package Marking Information
8-Lead PDIP
Example:
XXXXXXXX
T/XXXNNN
YYWW
23K256
I/P e3 1L7
0528
8-Lead SOIC (3.90 mm)
Example:
23K256I
SN e3 0528
1L7
XXXXXXXT
XXXXYYWW
NNN
8-Lead TSSOP
XXXX
TYWW
NNN
Legend: XX...X
T
Y
YY
WW
NNN
e3
Example:
K256
I837
1L7
Part number or part number code
Temperature (I, E)
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 (2 characters for small packages)
Pb-free JEDEC designator for Matte Tin (Sn)
Note:
For very small packages with no room for the Pb-free JEDEC designator
e3 , the marking will only appear on the outer carton or reel label.
Note:
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.
DS22100F-page 14
2008-2011 Microchip Technology Inc.
23A256/23K256
3
&'
!&"&4#*!(!!&
4%&
&#&
&&255***'
'54
N
NOTE 1
E1
1
3
2
D
E
A2
A
L
A1
c
e
eB
b1
b
6&!
'!
9'&!
7"')
%!
7,8.
7
7
7:
;
<
&
&
&
=
=
##44!!
-
1!&
&
=
=
"#&
"#>#&
.
-
-
##4>#&
.
<
: 9&
-<
-?
&
&
9
-
9#4!!
<
)
?
)
<
1
=
=
69#>#&
9
*9#>#&
: *+
1,
-
!"#$%&"' ()"&'"!&)
&#*&&&#
+%&,&!&
- '!
!#.#
&"#'
#%!
&"!
!
#%!
&"!
!!
&$#/!#
'!
#&
.0
1,21!'!
&$& "!
**&
"&&
!
* ,<1
2008-2011 Microchip Technology Inc.
DS22100F-page 15
23A256/23K256
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
DS22100F-page 16
2008-2011 Microchip Technology Inc.
23A256/23K256
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
2008-2011 Microchip Technology Inc.
DS22100F-page 17
23A256/23K256
!
""#$%& !'
3
&'
!&"&4#*!(!!&
4%&
&#&
&&255***'
'54
DS22100F-page 18
2008-2011 Microchip Technology Inc.
23A256/23K256
() )"* !
(+%+(
!
3
&'
!&"&4#*!(!!&
4%&
&#&
&&255***'
'54
D
N
E
E1
NOTE 1
1
2
b
e
c
A
φ
A2
A1
L
L1
6&!
'!
9'&!
7"')
%!
99..
7
7
7:
;
<
&
: 8&
=
?1,
=
##44!!
<
&#
%%
=
: >#&
.
##4>#&
.
-
?1,
##49&
-
-
3
&9&
9
?
3
&&
9
.3
3
&
R
=
<R
9#4!!
=
9#>#&
)
=
-
!"#$%&"' ()"&'"!&)
&#*&&&#
'!
!#.#
&"#'
#%!
&"!
!
#%!
&"!
!!
&$#''!#
- '!
#&
.0
1,2 1!'!
&$& "!
**&
"&&
!
.32 %'!
("!"*&
"&&
(%
%
'&
"
!!
* ,<?1
2008-2011 Microchip Technology Inc.
DS22100F-page 19
23A256/23K256
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
DS22100F-page 20
2008-2011 Microchip Technology Inc.
23A256/23K256
APPENDIX A:
REVISION HISTORY
Revision A (11/2008)
Original Release.
Revision B (12/2008)
Updates; Table 1-1, add Param. D011.
Revision C (01/2009)
Revised Section 2.5: Added a paragraph.
Revision D (04/2009)
Removed Preliminary status; Revised Standby
Current; Revised Table 1-1, Param. No. D009; Revised
TSSOP Package marking; Revised Product ID.
Revision E (08/2010)
Revised Table 1-1, Param. No. D009; Revised
Package Drawings.
Revision F (10/2011)
Revised Parameter D003 in Table 1-1: DC Characteristics.
2008-2011 Microchip Technology Inc.
DS22100F-page 21
23A256/23K256
NOTES:
DS22100F-page 22
2008-2011 Microchip Technology Inc.
23X256
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
Development Systems Information Line
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.
2008-2011 Microchip Technology Inc.
DS22100F-page 23
23X256
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: 23X256
Literature Number: DS22100F
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?
DS22100F-page 24
2008-2011 Microchip Technology Inc.
23A256/23K256
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
Device
Tape & Reel
X
/XX
Temp Range
Package
–
Examples:
a)
b)
Device:
23A256 =
23K256 =
256 Kbit, 1.8V, SPI Serial SRAM
256 Kbit, 3.6V, SPI Serial SRAM
Tape & Reel:
Blank
T
=
=
Standard packaging (tube)
Tape & Reel
Temperature
Range:
I
E
=
-40C to+85C
-40C to+125C
Package:
P
SN
ST
=
=
=
Plastic PDIP (300 mil body), 8-lead
Plastic SOIC (3.90 mml body), 8-lead
TSSOP, 8-lead
2008-2011 Microchip Technology Inc.
c)
23K256-I/ST = 256 Kbit, 3.6V Serial SRAM,
Industrial temp., TSSOP package
23A256T-I/SN = 256 Kbit, 1.8V Serial SRAM,
Industrial temp., Tape & Reel, SOIC package
23K256-E/ST = 256 Kbit, 3.6V Serial SRAM,
Automotive temp., TSSOP package
DS22100F-page 25
23A256/23K256
NOTES:
DS22100F-page 26
2008-2011 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,
KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, PICSTART,
PIC32 logo, rfPIC 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,
MXDEV, MXLAB, SEEVAL 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, chipKIT,
chipKIT logo, CodeGuard, dsPICDEM, dsPICDEM.net,
dsPICworks, dsSPEAK, ECAN, ECONOMONITOR,
FanSense, HI-TIDE, In-Circuit Serial Programming, ICSP,
Mindi, MiWi, MPASM, MPLAB Certified logo, MPLIB,
MPLINK, mTouch, Omniscient Code Generation, PICC,
PICC-18, PICDEM, PICDEM.net, PICkit, PICtail, REAL ICE,
rfLAB, Select Mode, Total Endurance, TSHARC,
UniWinDriver, WiperLock 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.
All other trademarks mentioned herein are property of their
respective companies.
© 2008-2011, Microchip Technology Incorporated, Printed in
the U.S.A., All Rights Reserved.
Printed on recycled paper.
ISBN: 978-1-61341-674-7
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.
2008-2011 Microchip Technology Inc.
DS22100F-page 27
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
Tower 6, The Gateway
Harbour City, Kowloon
Hong Kong
Tel: 852-2401-1200
Fax: 852-2401-3431
India - Bangalore
Tel: 91-80-3090-4444
Fax: 91-80-3090-4123
India - New Delhi
Tel: 91-11-4160-8631
Fax: 91-11-4160-8632
Austria - Wels
Tel: 43-7242-2244-39
Fax: 43-7242-2244-393
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
India - Pune
Tel: 91-20-2566-1512
Fax: 91-20-2566-1513
France - Paris
Tel: 33-1-69-53-63-20
Fax: 33-1-69-30-90-79
Japan - Yokohama
Tel: 81-45-471- 6166
Fax: 81-45-471-6122
Germany - Munich
Tel: 49-89-627-144-0
Fax: 49-89-627-144-44
Atlanta
Duluth, GA
Tel: 678-957-9614
Fax: 678-957-1455
Boston
Westborough, MA
Tel: 774-760-0087
Fax: 774-760-0088
Chicago
Itasca, IL
Tel: 630-285-0071
Fax: 630-285-0075
Cleveland
Independence, OH
Tel: 216-447-0464
Fax: 216-447-0643
Dallas
Addison, TX
Tel: 972-818-7423
Fax: 972-818-2924
Detroit
Farmington Hills, MI
Tel: 248-538-2250
Fax: 248-538-2260
Indianapolis
Noblesville, IN
Tel: 317-773-8323
Fax: 317-773-5453
Los Angeles
Mission Viejo, CA
Tel: 949-462-9523
Fax: 949-462-9608
Santa Clara
Santa Clara, CA
Tel: 408-961-6444
Fax: 408-961-6445
Toronto
Mississauga, Ontario,
Canada
Tel: 905-673-0699
Fax: 905-673-6509
Australia - Sydney
Tel: 61-2-9868-6733
Fax: 61-2-9868-6755
China - Beijing
Tel: 86-10-8569-7000
Fax: 86-10-8528-2104
China - Chengdu
Tel: 86-28-8665-5511
Fax: 86-28-8665-7889
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
China - Chongqing
Tel: 86-23-8980-9588
Fax: 86-23-8980-9500
Korea - Seoul
Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
China - Hangzhou
Tel: 86-571-2819-3187
Fax: 86-571-2819-3189
Malaysia - Kuala Lumpur
Tel: 60-3-6201-9857
Fax: 60-3-6201-9859
China - Hong Kong SAR
Tel: 852-2401-1200
Fax: 852-2401-3431
Malaysia - Penang
Tel: 60-4-227-8870
Fax: 60-4-227-4068
China - Nanjing
Tel: 86-25-8473-2460
Fax: 86-25-8473-2470
Philippines - Manila
Tel: 63-2-634-9065
Fax: 63-2-634-9069
China - Qingdao
Tel: 86-532-8502-7355
Fax: 86-532-8502-7205
Singapore
Tel: 65-6334-8870
Fax: 65-6334-8850
China - Shanghai
Tel: 86-21-5407-5533
Fax: 86-21-5407-5066
Taiwan - Hsin Chu
Tel: 886-3-5778-366
Fax: 886-3-5770-955
China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
Taiwan - Kaohsiung
Tel: 886-7-536-4818
Fax: 886-7-330-9305
China - Shenzhen
Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
Taiwan - Taipei
Tel: 886-2-2500-6610
Fax: 886-2-2508-0102
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Spain - Madrid
Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
UK - Wokingham
Tel: 44-118-921-5869
Fax: 44-118-921-5820
China - Xian
Tel: 86-29-8833-7252
Fax: 86-29-8833-7256
China - Xiamen
Tel: 86-592-2388138
Fax: 86-592-2388130
China - Zhuhai
Tel: 86-756-3210040
Fax: 86-756-3210049
DS22100F-page 28
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
Korea - Daegu
Tel: 82-53-744-4301
Fax: 82-53-744-4302
08/02/11
2008-2011 Microchip Technology Inc.