The Microchip Technology Inc. 25AA080A/B,
25LC080A/B (25XX080A/B
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. Access to the device is controlled
through a Chip Select (CS
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 25XX080A/B is available in standard packages
including 8-lead PDIP and SOIC, and advanced
packaging including 8-lead MSOP, and 8-lead TSSOP.
Pb-free (Pure Matte Sn) finish is also available.
*
) are 8 Kbit Serial
) input.
Package Types (not to scale)
CS
SO
WP
V
SS
PDIP/SOIC
(P, SN)
1
8
2
7
3
6
4
5
V
CC
HOLD
SCK
SI
TSSOP/MSOP
(ST, MS)
1
CS
2
SO
3
WP
4
V
SS
SPI is a registered trademark of Motorola Semiconductor.
*25XX080A/B is used in this document as a generic part
number for the 25AA080A/B, 25LC080A/B.
SS ......................................................................................................... -0.6V to VCC +1.0V
Storage temperature .................................................................................................................................-65°C to 150°C
Ambient temperature under bias...............................................................................................................-65°C to 125°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 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.
Note:This parameter is periodically sampled and not 100% tested.
AMB = -40°C to +85°C VCC = 1.8V to 5.5V
AMB = -40°C to +125°C VCC = 2.5V to 5.5V
±1µACS = VCC, VOUT = VSSTO VCC
AMB = 25°C, CLK = 1.0 MHz,
CC = 5.0V (Note)
V
6
mAmAVCC = 5.5V; FCLK = 10.0 MHz;
SO = Open
2.5
CC = 2.5V; FCLK = 5.0 MHz;
V
SO = Open
3mAVCC = 5.5V
5
1
µAµACS
V
CS
V
= VCC = 5.5V, Inputs tied to VCC or
SS, TAMB = -40°C TO +125°C
= VCC = 2.5V, Inputs tied to VCC or
SS, TAMB = -40°C TO +85°C
DS21808B-page 2 2003 Microchip Technology Inc.
TABLE 1-2:AC CHARACTERISTICS
25XX080A/B
AC CHARACTERISTICS
Param.
No.
1F
Sym.CharacteristicMin.Max.UnitsTest Conditions
CLKClock Frequency—
Industrial (I):T
Automotive (E): T
—
—
2T
CSSCS Setup Time50
100
150
3T
CSHCS Hold Time100
200
250
4T
CSDCS Disable Time50—ns—
5TsuData Setup Time10
20
30
6T
HDData Hold Time20
40
50
7T
8T
9T
RCLK Rise Time—500ns(Note 1)
FCLK Fall Time—500ns(Note 1)
HIClock High Time50
100
150
10T
LOClock Low Time50
100
150
11T
12T
13T
CLDClock Delay Time50—ns—
CLEClock Enable Time50—ns—
VOutput Valid from Clock
Low
—
—
—
14T
15T
HOOutput Hold Time0—ns(Note 1)
DISOutput Disable Time—
—
—
16T
HSHOLD Setup Time20
40
80
AMB = -40°C to +85°CVCC = 1.8V to 5.5V
AMB = -40°C to +125°C VCC = 2.5V to 5.5V
10
5
3
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
50
100
160
40
80
160
—
—
—
Note 1: This parameter is periodically sampled and not 100% tested.
2: 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 our web site:
www.microchip.com.
WC begins on the rising edge of CS after a valid write sequence and ends when the internal write cycle
3: T
is complete.
MHz
MHz
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
4.5V ≤ VCC≤ 5.5V
2.5V ≤ V
1.8V ≤ V
CC < 4.5V
CC < 2.5V
4.5V ≤ VCC≤ 5.5V
2.5V ≤ V
1.8V ≤ V
CC < 4.5V
CC < 2.5V
4.5V ≤ VCC≤ 5.5V
2.5V ≤ V
1.8V ≤ V
4.5V ≤ V
2.5V ≤ V
1.8V ≤ V
4.5V ≤ V
2.5V ≤ V
1.8V ≤ V
CC < 4.5V
CC < 2.5V
CC ≤ 5.5V
CC < 4.5V
CC < 2.5V
CC ≤ 5.5V
CC < 4.5V
CC < 2.5V
4.5V ≤ VCC≤ 5.5V
2.5V ≤ V
1.8V ≤ V
CC < 4.5V
CC < 2.5V
4.5V ≤ VCC≤ 5.5V
2.5V ≤ V
1.8V ≤ V
4.5V ≤ V
2.5V ≤ V
1.8V ≤ V
4.5V ≤ V
2.5V ≤ V
1.8V ≤ V
CC < 4.5V
CC < 2.5V
CC ≤ 5.5V
CC < 4.5V
CC < 2.5V
CC ≤ 5.5V (Note 1)
CC < 4.5V (Note 1)
CC < 2.5V (Note 1)
4.5V ≤ VCC≤ 5.5V
2.5V ≤ V
1.8V ≤ V
CC < 4.5V
CC < 2.5V
2003 Microchip Technology Inc.DS21808B-page 3
25XX080A/B
TABLE 1-2:AC CHARACTERISTICS (CONTINUED)
Industrial (I):T
Automotive (E): T
Param.
No.
AC CHARACTERISTICS
Sym.CharacteristicMin.Max.UnitsTest Conditions
17THHHOLD Hold Time20
40
80
18T
HZHOLD Low to Output
High-Z
30
60
160
19T
HVHOLD High to Output
Val id
30
60
160
20T
WCInternal Write Cycle Time—5ms(Note 3)
AMB = -40°C to +85°CVCC = 1.8V to 5.5V
AMB = -40°C to +125°C VCC = 2.5V to 5.5V
—
—
—
—
—
—
—
—
—
ns
ns
ns
ns
ns
ns
ns
ns
ns
21—Endurance1,000,000—E/W
Cycles
Note 1: This parameter is periodically sampled and not 100% tested.
2: 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 our web site:
www.microchip.com.
3: T
WC begins on the rising edge of CS after a valid write sequence and ends when the internal write cycle
is complete.
4.5V ≤ V
2.5V ≤ V
1.8V ≤ V
CC ≤ 5.5V
CC < 4.5V
CC < 2.5V
4.5V ≤ VCC≤ 5.5V (Note 1)
2.5V ≤ V
1.8V ≤ V
4.5V ≤ V
2.5V ≤ V
1.8V ≤ V
CC < 4.5V (Note 1)
CC < 2.5V (Note 1)
CC ≤ 5.5V
CC < 4.5V
CC < 2.5V
(Note 2)
TABLE 1-3:AC TEST CONDITIONS
AC Waveform:
LO = 0.2V—
V
HI = VCC - 0.2V (Note 1)
V
HI = 4.0V (Note 2)
V
Timing Measurement Reference Level
Input0.5 V
Output0.5 VCC
Note 1: For VCC≤ 4.0V
2: For V
CC > 4.0V
CC
DS21808B-page 4 2003 Microchip Technology Inc.
FIGURE 1-1:HOLD TIMING
CS
16
SCK
SO
n+2n+1nn-1
17
18
high-impedance
16
25XX080A/B
17
19
n
SI
HOLD
n+2n+1n
FIGURE 1-2:SERIAL INPUT TIMING
CS
2
Mode 1,1
Mode 0,0
SCK
65
SI
SO
MSB in
high-impedance
don’t care
7
8
LSB in
5
n
3
n-1
4
12
11
FIGURE 1-3:SERIAL OUTPUT TIMING
CS
9
10
SCK
13
SO
SI
2003 Microchip Technology Inc.DS21808B-page 5
MSB out
don’t care
14
3
Mode 1,1
Mode 0,0
15
ISB out
25XX080A/B
2.0FUNCTIONAL DESCRIPTION
2.1Principles of Operation
The 25XX080A/B are 1024 byte Serial EEPROMs
designed to interface directly with the Serial
Peripheral Interface (SPI) Port of many of today’s
popular microcontroller families, including
Microchip’s PICmicro
interface with microcontrollers that do not have a
built-in Synchronous Serial Port by using discrete
I/O lines programmed properly with the software.
The 25XX080A/B 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
be low and the HOLD
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
peripheral devices on the SPI bus, the user can assert
the HOLD
mode. After releasing the HOLD
resume from the point when the HOLD
goes low. If the clock line is shared with other
input and place the 25XX080A/B in ‘HOLD’
2.2Read Sequence
The device is selected by pulling CS low. The 8-bit read
instruction is transmitted to the 25XX080A/B followed
by the 16-bit address, with the six MSBs of the address
being don’t care bits. 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. 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 (03FFh), the address counter rolls over to
address 0000h allowing the read cycle to be continued
indefinitely. The read operation is terminated by raising
pin (Figure 2-1).
the CS
®
microcontrollers. It may also
pin must
pin must be high for the entire
pin, operation will
was asserted.
2.3Write Sequence
Prior to any attempt to write data to the 25XX080A/B,
the write enable latch must be set by issuing the WREN
instruction (Figure 2-4). This is done by setting CS
and then clocking out the proper instruction into the
25XX080A/B. After all eight bits of the instruction are
transmitted, the CS
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 because the write enable latch will not have been
properly set.
Once the write enable latch is set, the user may
proceed by setting the CS
instruction, followed by the 16-bit address, with the six
MSBs of the address being don’t care bits, and then the
data to be written. Up to 16 bytes (25XX080A) or 32
bytes (25XX080B) of data can be sent to the device
before a write cycle is necessary. The only restriction is
that all of the bytes must reside in the same page.
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.
For the data to be actually written to the array, the CS
must be brought high after the Least Significant bit (D0)
of the n
brought high at any other time, the write operation will
not be completed. Refer to Figure 2-2 and Figure 2-3
for more detailed illustrations on the byte write
sequence and the page write sequence respectively.
While the write is in progress, the Status Register may
be read to check the status of the WPEN, WIP, WEL,
BP1 and BP0 bits (Figure 2-6). A read attempt of a
memory array location will not be possible during a
write cycle. When the write cycle is completed, the
write enable latch is reset.