STMICROELECTRONICS M28C17

M28C16B
M28C17B
16 Kbit (2K x 8) Parallel EEPROM
With Software Data Protection
PRELIMINARY DATA
■
Fast Access Time: 90 ns at VCC=5V
■
Single Supply Voltage:
– 4.5 V to 5.5 V for M28CxxB
– 2.7 V to 3.6 V for M28CxxB-W
■
Low Power Consumption
■
Fast BYTE and PAGE WRITE (up to 64 Bytes)
– 3 ms at VCC=4.5 V
– 5 ms at VCC=2.7 V
■
Enhanced Write Detection and Monitoring:
– Data Polling
PLCC32 (K)
– Toggle Bit
– Page Load Timer Status
■
JEDEC Approved Bytewide Pin-Out
■
Software Data Protection
■
100000 Erase/Write Cycles (minimum)
■
Data Retention (minimum): 40 Years
DESCRIPTION
The M28C16B and M28C17B devices consist of
2048x8 bits of low power, parallel EEPROM, fabricated with STMicroelectronics’ proprietary single
polysilicon CMOS technology. The devices offer
fast access time, with low power dissipation, and
require a single voltage supply.
Figure 1. Logic Diagram
VCC
Table 1. Signal Names
A0-A10
Address Input
DQ0-DQ7
Data Input / Output
W
Write Enable
E
Chip Enable
G
Output Enable
RB
Ready/Busy (M28C17B only)
VCC
Supply Voltage
VSS
Ground
11
8
A0-A10
W
DQ0-DQ7
M28C16B
M28C17B
E
RB
(M28C17B only)
G
VSS
AI02816
February 1999
This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
1/17
M28C16B, M28C17B
A7
NC
NC
RB
VCC
W
NC
Figure 2B. PLLC Connections
NC
NC
VCC
W
NC
A7
NC
Figure 2A. PLLC Connections
1 32
A6
A5
A4
A3
A2
A1
A0
NC
DQ0
9
M28C16B
1 32
25
A8
A9
NC
NC
G
A10
E
DQ7
DQ6
A6
A5
A4
A3
A2
A1
A0
NC
DQ0
9
M28C17B
DQ1
DQ2
VSS
NC
DQ3
DQ4
DQ5
17
DQ1
DQ2
VSS
NC
DQ3
DQ4
DQ5
17
25
A8
A9
NC
NC
G
A10
E
DQ7
DQ6
AI02817
AI02830
Note: 1. NC = Not Connected
Note: 1. NC = Not Connected
The M28C17B is like the M28C16B in every way,
except that it has an extra ready/busy (RB) output.
The device has been designed to offer a flexible
microcontroller interface, featuring software handshaking, with Data Polling and Toggle Bit. The device supports a 64 byte Page Write operation.
Software Data Protection (SDP) is also supported,
using the standard JEDEC algorithm.
DEVICE OPERATION
In order to prevent data corruption and inadvertent
write operations, an internal VCC comparator inhibits the Write operations if the V CC voltage is
lower than V WI (see Table 4A). Once the voltage
applied on the VCC pin goes over the VWI threshold (V CC>VWI), write access to the memory is allowed after a time-out t PUW, as specified in Table
4A.
Further protection against data corruption is offered by the E and W low pass filters: any glitch,
on the E and W inputs, with a pulse width less than
10 ns (typical) is internally filtered out to prevent
inadvertent write operations to the memory.
Read
The device is accessed like a static RAM. When E
and G are low, and W is high, the contents of the
addressed location are presented on the I/O pins.
Otherwise, when either G or E is high, the I/O pins
revert to their high impedance state.
Write
Write operations are initiated when both W and E
are low and G is high. The device supports both
W-controlled and E-controlled write cycles (as
shown in Figure 11 and Figure 12). The address is
latched during the falling edge of W or E (which
ever occurs later) and the data is latched on the
rising edge of W or E (which ever occurs first). After a delay, tWLQ5H, that cannot be shorter than the
value specified in Table 10A, the internal write cycle starts. It continues, under internal timing control, until the write operation is complete. The
commencement of this period can be detected by
reading the Page Load Timer Status on DQ5. The
SIGNAL DESCRIPTION
The external connections to the device are summarized in Table 1, and their use in Table 3.
Addresses (A0-A10). The address inputs are
used to select one byte from the memory array
during a read or write operation.
Data In/Out (DQ0-DQ7). The contents of the data
byte are written to, or read from, the memory array
through the Data I/O pins.
Chip Enable (E). The chip enable input must be
held low to enable read and write operations.
When Chip Enable is high, power consumption is
reduced.
Output Enable (G). The Output Enable input controls the data output buffers, and is used to initiate
read operations.
Write Enable (W). The Write Enable input controls
whether the addressed location is to be read, from
or written to.
Ready/Busy (RB). Ready/Busy (on the M28C17B
only) is an open drain output that can be used to
detect the end of the internal write cycle.
2/17
M28C16B, M28C17B
Table 2. Absolute Maximum Ratings 1
Symbol
Value
Unit
Ambient Operating Temperature
-40 to 125
°C
TSTG
Storage Temperature
-65 to 150
°C
VCC
Supply Voltage
-0.3 to 6.5
V
VIO
Input or Output Voltage
-0.6 to VCC+0.6
V
VI
Input Voltage
-0.3 to 6.5
V
4000
V
TA
VESD
Parameter
Electrostatic Discharge Voltage (Human Body model) 2
Note: 1. Except for the rating “Operating Temperature Range”, stresses above those listed in the Table “Absolute Maximum Ratings” may
cause permanent damage to the device. These are stress ratings only, and operation of the device at these or any other conditions
above those indicated in the Operating sections of this specification is not implied. Exposure to Absolute Maximum Rating conditions for extended periods may affect device reliability. Refer also to the ST SURE Program and other relevant quality documents.
2. MIL-STD-883C, 3015.7 (100 pF, 1500 Ω)
Figure 3. Block Diagram
E
A6-A10
(Page Address)
A0-A5
RESET
ADDRESS
LATCH
X DECODE
VPP GEN
G
W
CONTROL LOGIC
16K ARRAY
ADDRESS
LATCH
Y DECODE
SENSE AND DATA LATCH
I/O BUFFERS
PAGE LOAD
TIMER STATUS
TOGGLE BIT
DATA POLLING
DQ0-DQ7
AI02818
3/17
M28C16B, M28C17B
Table 3. Operating Modes 1
Mode
E
G
W
DQ0-DQ7
Stand-by
1
X
X
Hi-Z
Output Disable
X
1
X
Hi-Z
Write Disable
X
X
1
Hi-Z
Read
0
0
1
Data Out
Write
0
1
0
Data In
Chip Erase
0
V
0
Hi-Z
Note: 1. 0=VIL; 1=VIH; X = VIH or VIL; V=12V ± 5%.
end of the cycle can be detected by reading the
status of the Data Polling and the Toggle Bit functions on DQ7 and DQ6.
Page Write
The Page Write mode allows up to 64 bytes to be
written on a single page in a single go. This is
achieved through a series of successive Write operations, no two of which are separated by more
than the tWLQ5H value (as specified in Table 10A).
The page write can be initiated during any byte
write operation. Following the first byte write instruction the host may send another address and
data with a minimum data transfer rate of:
1/t WLQ5H.
The internal write cycle can start at any instant after tWLQ5H. Once initiated, the write operation is internally timed, and continues, uninterrupted, until
completion.
All bytes must be located on the same page address (A10-A6 must be the same for all bytes).
Otherwise, the Page Write operation is not executed.
As with the single byte Write operation, described
above, the DQ5, DQ6 and DQ7 lines can be used
to detect the beginning and end of the internally
controlled phase of the Page Write cycle.
Software Data Protection (SDP)
The device offers a software-controlled write-protection mechanism that allows the user to inhibit all
write operations to the device. This can be useful
for protecting the memory from inadvertent write
cycles that may occur during periods of instability
(uncontrolled bus conditions when excessive
noise is detected, or when power supply levels are
outside their specified values).
By default, the device is shipped in the “unprotected” state: the memory contents can be freely
changed by the user. Once the Software Data Protection Mode is enabled, all write commands are
Table 4A. Power-Up Timing1 for M28CxxB (5V range)
(TA = 0 to 70 °C or -40 to 85 °C; VCC = 4.5 to 5.5 V)
Symbol
Parameter
Min.
Max.
Unit
tPUR
Time Delay to Read Operation
1
µs
tPUW
Time Delay to Write Operation (once VCC ≥ VWI)
10
ms
3.0
4.2
V
Min.
Max.
Unit
VWI
Write Inhibit Threshold
Note: 1. Sampled only, not 100% tested.
Table 4B. Power-Up Timing1 for M28CxxB-W (3V range)
(TA = 0 to 70 °C or -40 to 85 °C; VCC = 2.7 to 3.6 V)
Symbol
Parameter
tPUR
Time Delay to Read Operation
1
µs
tPUW
Time Delay to Write Operation (once VCC ≥ VWI)
15
ms
2.5
V
VWI
Write Inhibit Threshold
Note: 1. Sampled only, not 100% tested.
4/17
1.5
M28C16B, M28C17B
Figure 4. Software Data Protection Enable Algorithm and Memory Write
Write AAh in
Address 555h
Page Write
Timing
(see note 1)
Write AAh in
Address 555h
Page Write
Timing
(see note 1)
Write 55h in
Address 2AAh
Write 55h in
Address 2AAh
Write A0h in
Address 555h
Write A0h in
Address 555h
Write
is Enabled
SDP is set
Physical
Page Write
Instruction
SDP Enable Algorithm
Page Write
(1 up to 64 bytes)
Write to Memory
When SDP is SET
AI02819
Note: 1. The most significant address bits (A10 to A6) differ during these specific Page Write operations.
ignored, and have no effect on the memory contents.
The device remains in this mode until a valid Software Data Protection disable sequence is received. The device reverts to its “unprotected”
state.
The status of the Software Data Protection (enabled or disabled) is represented by a non-volatile
latch, and is remembered across periods of the
power being off.
The Software Data Protection Enable command
consists of the writing of three specific data bytes
to three specific memory locations (each location
being on a different page), as shown in Figure 4.
Similarly to disable the Software Data Protection,
the user has to write specific data bytes into six dif-
ferent locations, as shown in Figure 6. This complex series of operations protects against the
chance of inadvertent enabling or disabling of the
Software Data Protection mechanism.
Figure 6. Software Data Protection Disable
Algorithm
Write AAh in
Address 555h
Write 55h in
Address 2AAh
Page Write
Timing
Figure 5. Status Bit Assignment
Write 80h in
Address 555h
Write AAh in
Address 555h
DQ7
DQ6
DQ5
DQ4
DQ3
DQ2
DQ1
DQ0
DP
TB
PLTS
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
DP
TB
PLTS
Hi-Z
Write 55h in
Address 2AAh
Write 20h in
Address 555h
= Data Polling
= Toggle Bit
= Page Load Timer Status
= High impedance
Unprotected State
AI02815
AI02820
5/17
M28C16B, M28C17B
Figure 7. Chip Erase AC Waveforms
tWHEH
E
G
tGLWH
W
tELWL
tWLWH2
tWHRH
AI01484B
Table 5. Chip Erase AC Characteristics1
(TA = 0 to 70 °C or -40 to 85 °C; VCC = 4.5 to 5.5 V or 2.7 to 3.6 V)
Symbol
Parameter
Test Condition
Min.
Max.
Unit
tELWL
Chip Enable Low to Write Enable Low
G = VCC + 7V
1
µs
tWHEH
Write Enable High to Chip Enable High
G = VCC + 7V
0
ns
tWLWH2
Write Enable Low to Write Enable High
G = VCC + 7V
10
ms
tGLWH
Output Enable Low to Write Enable High
G = VCC + 7V
1
µs
tWHRH
Write Enable High to Write Enable Low
G = VCC + 7V
3
ms
Note: 1. Sampled only, not 100% tested.
When SDP is enabled, the memory array can still
have data written to it, but the sequence is more
complex (and hence better protected from inadvertent use). The sequence is as shown in Figure
4. This consists of an unlock key, to enable the
write action, at the end of which the SDP continues
to be enabled. This allows the SDP to be enabled,
and data to be written, within a single Write cycle
(tWC).
Software Chip Erase
The contents of the entire memory are erased (set
to FFh) by holding Chip Enable (E) low, and holding Output Enable (G) at VCC+7.0V. The chip is
cleared when a 10 ms low pulse is applied to the
Write Enable (W) signal (see Figure 7 and Table 5
for details).
Status Bits
The devices provide three status bits (DQ7, DQ6
and DQ5), for use during write operations. These
allow the application to use the write time latency
of the device for getting on with other work. These
signals are available on the I/O port bits DQ7, DQ6
and DQ5 (but only during programming cycle,
6/17
once a byte or more has been latched into the
memory).
Data Polling bit (DQ7). The internally timed write
cycle starts after tWLQ5H (defined in Table 10A)
has elapsed since the previous byte was latched in
to the memory. The value of the DQ7 bit of this last
byte, is used as a signal throughout this write operation: it is inverted while the internal write operation is underway, and is inverted back to its
original value once the operation is complete.
Toggle bit (DQ6). The device offers another way
for determining when the internal write cycle is
completed. During the internal Erase/Write cycle,
DQ6 toggles from ’0’ to ’1’ and ’1’ to ’0’ (the first
read value being ’0’) on subsequent attempts to
read any byte of the memory. When the internal
write cycle is complete, the toggling is stopped,
and the values read on DQ7-DQ0 are those of the
addressed memory byte. This indicates that the
device is again available for new Read and Write
operations.
Page Load Timer Status bit (DQ5). An internal
timer is used to measure the period between suc-
M28C16B, M28C17B
Table 6A. Read Mode DC Characteristics for M28CxxB (5V range)
(TA = 0 to 70 °C or -40 to 85 °C; VCC = 4.5 to 5.5 V)
Symbol
Parameter
Test Condition
ILI
Input Leakage Current
ILO
Output Leakage Current
Max.
Unit
0 V ≤ VIN ≤ VCC
10
µA
0 V ≤ VOUT ≤ VCC
10
µA
Supply Current (TTL inputs)
E = VIL, G = VIL , f = 5 MHz
30
mA
Supply Current (CMOS inputs)
E = VIL, G = VIL , f = 5 MHz
25
mA
ICC1 1
Supply Current (Stand-by) TTL
E = VIH
1
mA
ICC2 1
Supply Current (Stand-by) CMOS
E > VCC - 0.3V
100
µA
ICC 1
Min.
VIL
Input Low Voltage
-0.3
0.8
V
VIH
Input High Voltage
2
VCC + 0.5
V
VOL
Output Low Voltage
IOL = 2.1 mA
0.4
V
VOH
Output High Voltage
IOH = -400 µA
2.4
V
Note: 1. All inputs and outputs open circuit.
Table 6B. Read Mode DC Characteristics for M28CxxB-W (3V range)
(TA = 0 to 70 °C or -40 to 85 °C; VCC = 2.7 to 3.6 V)
Symbol
Parameter
Test Condition
ILI
Input Leakage Current
ILO
Output Leakage Current
ICC 1
Supply Current (CMOS inputs)
ICC2 1
Supply Current (Stand-by) CMOS
Min.
Max.
Unit
0 V ≤ VIN ≤ VCC
10
µA
0 V ≤ VOUT ≤ VCC
10
µA
E = VIL, G = VIL , f = 5 MHz, VCC = 3.3V
8
mA
E = VIL, G = VIL , f = 5 MHz, VCC = 3.6V
10
mA
E > VCC - 0.3V
20
µA
VIL
Input Low Voltage
-0.3
0.6
V
VIH
Input High Voltage
2
VCC + 0.5
V
VOL
Output Low Voltage
IOL = 1.6 mA
0.2 VCC
V
VOH
Output High Voltage
IOH = -400 µA
0.8 VCC
V
Note: 1. All inputs and outputs open circuit.
cessive Write operations, up to t WLQ5H (defined in
Table 10A). The DQ5 line is held low to show
when this timer is running (hence showing that the
device has received one write operation, and is
waiting for the next). The DQ5 line is held high
when the counter has overflowed (hence showing
that the device is now starting the internal write to
the memory array).
7/17
M28C16B, M28C17B
Table 7. Input and Output Parameters 1 (TA = 25 °C, f = 1 MHz)
Symbol
CIN
COUT
Parameter
Test Condition
Input Capacitance
Output Capacitance
Min.
Max.
Unit
VIN = 0 V
6
pF
VOUT = 0 V
12
pF
Note: 1. Sampled only, not 100% tested.
Table 8. AC Measurement Conditions
≤ 20 ns
Input Rise and Fall Times
Input Pulse Voltages
0.4 V to 2.4 V
Input and Output Timing Reference Voltages
0.8 V to 2.0 V
Figure 8. AC Testing Input Output Waveforms
Figure 9. AC Testing Equivalent Load Circuit
IOL
2.4V
0.4V
2.0V
0.8V
DEVICE
UNDER
TEST
OUT
IOH
CL = 100pF
AI02821
8/17
CL includes JIG capacitance
AI02102B
M28C16B, M28C17B
Table 9A. Read Mode AC Characteristics for M28CxxB (5V range)
(TA = 0 to 70 °C or -40 to 85 °C; VCC = 4.5 to 5.5 V)
M28CxxB
Symbol
Alt.
Parameter
Test
Condition
-90
Min
-12
Max
Min
Unit
Max
tAVQV
tACC
Address Valid to Output Valid
E = VIL,
G = VIL
90
120
ns
tELQV
tCE
Chip Enable Low to Output Valid
G = VIL
90
120
ns
tGLQV
tOE
Output Enable Low to Output Valid
E = VIL
40
45
ns
tEHQZ1
tDF
Chip Enable High to Output Hi-Z
G = VIL
0
40
0
45
ns
tGHQZ1
tDF
Output Enable High to Output Hi-Z
E = VIL
0
40
0
45
ns
tAXQX
tOH
Address Transition to Output Transition
E = VIL,
G = VIL
0
0
ns
Note: 1. Output Hi-Z is defined as the point at which data is no longer driven.
Table 9B. Read Mode AC Characteristics for M28CxxB-W (3V range)
(TA = 0 to 70 °C or -40 to 85 °C; VCC = 2.7 to 3.6 V)
M28CxxB-W
Symbol
Alt.
Parameter
Test
Condition
-12
Min
-15
Max
Min
Unit
Max
tAVQV
tACC
Address Valid to Output Valid
E = VIL,
G = VIL
120
150
ns
tELQV
tCE
Chip Enable Low to Output Valid
G = VIL
120
150
ns
tGLQV
tOE
Output Enable Low to Output Valid
E = VIL
80
80
ns
tEHQZ1
tDF
Chip Enable High to Output Hi-Z
G = VIL
0
45
0
50
ns
tGHQZ1
tDF
Output Enable High to Output Hi-Z
E = VIL
0
45
0
50
ns
tAXQX
tOH
Address Transition to Output Transition
E = VIL,
G = VIL
0
0
ns
Note: 1. Output Hi-Z is defined as the point at which data is no longer driven.
9/17
M28C16B, M28C17B
Table 10A. Write Mode AC Characteristics for M28CxxB (5V range)
(TA = 0 to 70 °C or -40 to 85 °C; VCC = 4.5 to 5.5 V)
M28C17B
Symbol
Alt.
Parameter
Test Condition
Unit
Min
Max
tAVWL
tAS
Address Valid to Write Enable Low
E = VIL, G = VIH
0
ns
tAVEL
tAS
Address Valid to Chip Enable Low
G = VIH, W = VIL
0
ns
tELWL
tCES
Chip Enable Low to Write Enable Low
G = VIH
0
ns
tGHWL
tOES
Output Enable High to Write Enable Low
E = VIL
0
ns
tGHEL
tOES
Output Enable High to Chip Enable Low
W = VIL
0
ns
tWLEL
tWES
Write Enable Low to Chip Enable Low
G = VIH
0
ns
tWLAX
tAH
Write Enable Low to Address Transition
50
ns
tELAX
tAH
Chip Enable Low to Address Transition
50
ns
tWLDV
tDV
Write Enable Low to Input Valid
E = VIL, G = VIH
1
µs
tELDV
tDV
Chip Enable Low to Input Valid
G = VIH, W = VIL
1
µs
tELEH
tWP
Chip Enable Low to Chip Enable High
50
ns
tWHEH
tCEH
Write Enable High to Chip Enable High
0
ns
tWHGL
tOEH
Write Enable High to Output Enable Low
0
ns
tEHGL
tOEH
Chip Enable High to Output Enable Low
0
ns
tEHWH
tWEH
Chip Enable High to Write Enable High
0
ns
tWHDX
tDH
Write Enable High to Input Transition
0
ns
tEHDX
tDH
Chip Enable High to Input Transition
0
ns
tWHWL
tWPH
Write Enable High to Write Enable Low
50
ns
tWLWH
tWP
Write Enable Low to Write Enable High
50
ns
tWLQ5H
tBLC
Time-out After the Last Byte Write
100
µs
tQ5HQ5X
tWC
Write Cycle Time
tDVWH
tDS
Data Valid before Write Enable High
50
ns
tDVEH
tDS
Data Valid before Chip Enable High
50
ns
10/17
3
ms
M28C16B, M28C17B
Table 10B. Write Mode AC Characteristics for M28CxxB-W (3V range)
(TA = 0 to 70 °C or -40 to 85 °C; VCC = 2.7 to 3.6 V)
M28C17B-xxW
Symbol
Alt.
Parameter
Test Condition
Unit
Min
Max
tAVWL
tAS
Address Valid to Write Enable Low
E = VIL, G = VIH
0
ns
tAVEL
tAS
Address Valid to Chip Enable Low
G = VIH, W = VIL
0
ns
tELWL
tCES
Chip Enable Low to Write Enable Low
G = VIH
0
ns
tGHWL
tOES
Output Enable High to Write Enable Low
E = VIL
0
ns
tGHEL
tOES
Output Enable High to Chip Enable Low
W = VIL
0
ns
tWLEL
tWES
Write Enable Low to Chip Enable Low
G = VIH
0
ns
tWLAX
tAH
Write Enable Low to Address Transition
100
ns
tELAX
tAH
Chip Enable Low to Address Transition
100
ns
tWLDV
tDV
Write Enable Low to Input Valid
E = VIL, G = VIH
1
µs
tELDV
tDV
Chip Enable Low to Input Valid
G = VIH, W = VIL
1
µs
tELEH
tWP
Chip Enable Low to Chip Enable High
100
1000
ns
tWHEH
tCEH
Write Enable High to Chip Enable High
0
ns
tWHGL
tOEH
Write Enable High to Output Enable Low
0
ns
tEHGL
tOEH
Chip Enable High to Output Enable Low
0
ns
tEHWH
tWEH
Chip Enable High to Write Enable High
0
ns
tWHDX
tDH
Write Enable High to Input Transition
0
ns
tEHDX
tDH
Chip Enable High to Input Transition
0
ns
tWHWL
tWPH
Write Enable High to Write Enable Low
50
tWLWH
tWP
Write Enable Low to Write Enable High
100
ns
tWLQ5H
tBLC
Time-out after the last byte write
100
µs
tQ5HQ5X
tWC
Write Cycle Time
tDVWH
tDS
Data Valid before Write Enable High
50
ns
tDVEH
tDS
Data Valid before Chip Enable High
50
ns
1000
5
ns
ms
11/17
M28C16B, M28C17B
Figure 10. Read Mode AC Waveforms (with Write Enable, W, high)
VALID
A0-A10
tAVQV
tAXQX
E
tGLQV
tEHQZ
G
tELQV
tGHQZ
DQ0-DQ7
Hi-Z
DATA OUT
AI02822
Note: 1. Write Enable (W) = VIH
Figure 11. Write Mode AC Waveforms (Write Enable, W, controlled)
VALID
A0-A10
tAVWL
tWLAX
E
tELWL
tWHEH
G
tGHWL
tWLWH
tWHGL
W
tWLDV
DQ0-DQ7
tWHWL
DATA IN
tDVWH
tWHDX
RB
tWHRL
AI02823
12/17
M28C16B, M28C17B
Figure 12. Write Mode AC Waveforms (Chip Enable, E, controlled)
VALID
A0-A10
tAVEL
tELAX
E
tGHEL
tELEH
G
tWLEL
tEHGL
W
tELDV
tEHWH
DATA IN
DQ0-DQ7
tDVEH
tEHDX
RB
tEHRL
AI02824
Figure 13. Page Write Mode AC Waveforms (Write Enable, W, controlled)
Addr 0
A0-A10
Addr 1
Addr 2
Addr n
E
G
tWHWL
W
tWLWH
DQ0-DQ7 (in)
Byte 0
Byte 1
Byte 2
Byte n
DQ5 (out)
tWHRL
tWLQ5H
tQ5HQ5X
RB
AI02825
13/17
M28C16B, M28C17B
Figure 14. Software Protected Write Cycle Waveforms
G
E
tWLWH
tWHWL
tWHWH
W
tAVEL
tWLAX
A0-A5
Byte Address
tWHDX
A6-A10
555h
2AAh
555h
Page Address
tDVWH
DQ0-DQ7
AAh
55h
Byte 0
A0h
Byte 62
Byte 63
AI02826
Note: 1. A10 to A6 must specify the same page address during each high-to-low transition of W (or E). G must be high only when W and E
are both low.
Figure 15. Data Polling Sequence Waveforms
A0-A10
Address of the last byte of the Page Write instruction
E
G
W
DQ7
DQ7
Last WRITE
DQ7
DQ7
DQ7
Internal Write Sequence
DQ7
Ready
AI02827
14/17
M28C16B, M28C17B
Figure 16. Toggle Bit Sequence Waveforms
A0-A10
E
G
W
DQ6
(1)
TOGGLE
Internal Write Sequence
Last WRITE
Ready
AI02828
Note: 1. The Toggle Bit is first set to ‘0’.
Table 11. Ordering Information Scheme
Example:
M28C16
– 120
W
K
6
TR
Option
Ready/Busy
16
Pin 1 = Not Connected
17
Pin 1 = Ready/Busy
TR
Speed
Tape and Reel Packing
Temperature Range
90
90 ns (5V range only)
1
0 °C to 70 °C
120
120 ns
6
–40 °C to 85 °C
150
150 ns (3V range only)
Operating Voltage
blank 4.5 V to 5.5 V
W
Package
K
PLCC32
2.7 V to 3.6 V
ORDERING INFORMATION
Devices are shipped from the factory with the
memory content set at all ‘1’s (FFh).
The notation used for the device number is as
shown in Table 11. For a list of available options
(speed, package, etc.) or for further information on
any aspect of this device, please contact the ST
Sales Office nearest to you.
15/17
M28C16B, M28C17B
Table 12. PLCC32 - 32 lead Plastic Leaded Chip Carrier, rectangular
mm
Symbol
Typ.
inches
Min.
Max.
A
2.54
A1
Min.
Max.
3.56
0.100
0.140
1.52
2.41
0.060
0.095
A2
–
0.38
–
0.015
B
0.33
0.53
0.013
0.021
B1
0.66
0.81
0.026
0.032
D
12.32
12.57
0.485
0.495
D1
11.35
11.56
0.447
0.455
D2
9.91
10.92
0.390
0.430
E
14.86
15.11
0.585
0.595
E1
13.89
14.10
0.547
0.555
E2
12.45
13.46
0.490
0.530
–
–
–
–
0.00
0.25
0.000
0.010
–
–
–
–
e
1.27
F
R
0.89
Typ.
0.050
0.035
N
32
32
Nd
7
7
Ne
9
9
CP
0.10
0.004
Figure 17. PLCC (K)
D
D1
A1
A2
1 N
B1
E1 E
Ne
e
D2/E2
F
B
0.51 (.020)
1.14 (.045)
A
Nd
R
PLCC
Note: 1. Drawing is not to scale.
16/17
CP
M28C16B, M28C17B
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of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted
by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject
to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not
authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
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17/17