AT28HC256
Military Grade 256-Kbit (32,768 x 8) High-Speed
Paged Parallel EEPROM
Features
•
•
•
•
•
•
•
•
•
•
•
Fast Read Access Time: 90 ns
Automatic Page Write Operation:
– Internally organized as 32,768 x 8 (256K)
– Internal address and data latches for 64 bytes
– Internal control timer
Fast Write Cycle Time:
– Page Write cycle time: 3 ms or 10 ms maximum
– 1 to 64-byte Page Write operation
Low-Power Dissipation:
– 80 mA active current
– 3 mA CMOS standby current
Hardware and Software Data Protection
DATA Polling for End of Write Detection
High Reliability CMOS Technology:
– Endurance: 10,000 or 100,000 cycles
– Data retention: 10 years
Single 5V ± 10% Supply
CMOS and TTL Compatible Inputs and Outputs
®
JEDEC Approved Byte-Wide Pinout
Full Military Temperature Range
Packages
•
32-Lead CERDIP, 32-Lead Flatpack, 32-Lead CLCC and 30-Pin PGA
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 1
AT28HC256
Table of Contents
Features......................................................................................................................................................... 1
Packages........................................................................................................................................................1
1.
Package Types (not to scale)..................................................................................................................4
2.
Pin Descriptions...................................................................................................................................... 5
3.
Description.............................................................................................................................................. 6
3.1.
4.
Block Diagram.............................................................................................................................. 6
Electrical Characteristics.........................................................................................................................7
4.1.
4.2.
4.3.
4.4.
Absolute Maximum Ratings..........................................................................................................7
DC and AC Operating Range.......................................................................................................7
DC Characteristics....................................................................................................................... 7
Pin Capacitance........................................................................................................................... 8
5.
Normalized ICC Graphics.........................................................................................................................9
6.
Device Operation.................................................................................................................................. 10
6.1.
6.2.
6.3.
6.4.
6.5.
6.6.
6.7.
6.8.
6.9.
6.10.
6.11.
6.12.
6.13.
6.14.
6.15.
6.16.
6.17.
7.
Packaging Information.......................................................................................................................... 21
7.1.
8.
Operating Modes........................................................................................................................ 11
AC Read Characteristics............................................................................................................ 11
AC Read Waveforms..................................................................................................................12
Input Test Waveforms and Measurement Level......................................................................... 12
Output Test Load........................................................................................................................ 12
AC Write Characteristics............................................................................................................ 13
AC Write Waveforms.................................................................................................................. 13
Page Mode Characteristics........................................................................................................ 14
Page Mode Write Waveforms(1,2)............................................................................................... 15
Chip Erase Waveforms...............................................................................................................15
Software Data Protection Enable Algorithm(1)............................................................................16
Software Data Protection Disable Algorithm(1)...........................................................................17
Software Protected Program Cycle Waveform(1,2)..................................................................... 18
Data Polling Characteristics(1)....................................................................................................18
Data Polling Waveforms............................................................................................................. 19
Toggle Bit Characteristics(1)....................................................................................................... 19
Toggle Bit Waveforms.................................................................................................................19
Package Marking Information.....................................................................................................21
Revision History.................................................................................................................................... 26
The Microchip Website.................................................................................................................................27
Product Change Notification Service............................................................................................................27
Customer Support........................................................................................................................................ 27
Product Identification System.......................................................................................................................28
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 2
AT28HC256
Microchip Devices Code Protection Feature................................................................................................ 29
Legal Notice................................................................................................................................................. 30
Trademarks.................................................................................................................................................. 30
Quality Management System....................................................................................................................... 31
Worldwide Sales and Service.......................................................................................................................32
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 3
AT28HC256
Package Types (not to scale)
Package Types (not to scale)
32-Pad CLCC(1)
Top View
A7
A12
A14
DC
VCC
WE
A13
28-Lead PGA
4
3
2
1
32
31
30
5
6
7
8
9
10
11
12
13
29
28
27
26
25
24
23
22
21
A8
A9
A11
NC
OE
A10
CE
I/O7
I/O6
14
15
16
17
18
19
20
A6
A5
A4
A3
A2
A1
A0
NC
I/O0
Top View
I/O1
I/O2
GND
DC
I/O3
I/O4
I/O5
1.
28-Lead Cerdip/Flatpack
Top View
A14
A12
A7
A6
A5
A4
A3
A2
A1
A0
I/O0
I/O1
I/O2
GND
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
VCC
WE
A13
A8
A9
A11
OE
A10
CE
I/O7
I/O6
I/O5
I/O4
I/O3
Note:
1. CLCC package pins 1 and 17 are “Don’t Connect”.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 4
AT28HC256
Pin Descriptions
2.
Pin Descriptions
The descriptions of the pins are listed in Table 2-1.
Table 2-1. Pin Function Table
Name
32‑Lead CERDIP
32-Lead CLCC
DC
A14
A12
A7
A6
A5
A4
A3
A2
A1
A0
NC
I/O0
I/O1
I/O2
GND
DC
I/O3
I/O4
I/O5
I/O6
I/O7
CE
A10
OE
NC
A11
A9
A8
A13
WE
VCC
—
1
2
3
4
5
6
7
8
9
10
—
11
12
13
14
—
15
16
17
18
19
20
21
22
—
23
24
25
26
27
28
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
© 2020 Microchip Technology Inc.
32-Lead
FLATPACK
—
1
2
3
4
5
6
7
8
9
10
—
11
12
13
14
—
15
16
17
18
19
20
21
22
—
23
24
25
26
27
28
Datasheet
30‑Pin PGA
—
1
2
3
4
5
6
7
8
9
10
—
11
12
13
14
—
15
16
17
18
19
20
21
22
—
23
24
25
26
27
28
Function
Don’t Connect
Address
Address
Address
Address
Address
Address
Address
Address
Address
Address
No Connect
Data Input/Output
Data Input/Output
Data Input/Output
Ground
Don’t Connect
Data Input/Output
Data Input/Output
Data Input/Output
Data Input/Output
Data Input/Output
Chip Enable
Address
Output Enable
No Connect
Address
Address
Address
Address
Write Enable
Device Power
Supply
DS20006352A-page 5
AT28HC256
Description
3.
Description
The AT28HC256 is a high‑performance Electrically Erasable and Programmable Read‑Only Memory (EEPROM).
Its 256‑Kb memory is organized as 32,768 words by 8 bits. Manufactured with Microchip’s advanced nonvolatile
CMOS technology, the device offers access times to 90 ns with power dissipation of just 440 mW. When the device is
deselected, the CMOS standby current is less than 5 mA.
The AT28HC256 is accessed like a Static RAM for the read or write cycle without the need for external components.
The device contains a 64‑byte page register to allow writing of up to 64 bytes simultaneously. During a write cycle,
the address and 1 to 64 bytes of data are internally latched, freeing the address and data bus for other operations.
Following the initiation of a write cycle, the device will automatically write the latched data using an internal control
timer. The end of a write cycle can be detected by DATA Polling of I/O7. Once the end of a write cycle has been
detected, a new access for a read or write can begin.
The AT28HC256 has additional features to ensure high quality and manufacturability. The device utilizes internal
error correction for extended endurance and improved data retention characteristics. An optional software data
protection mechanism is available to guard against inadvertent writes. The device also includes an extra 64 bytes of
EEPROM for device identification or tracking.
3.1
Block Diagram
VCC
Data Inputs/Outputs
I/O0-I/O7
GND
OE
WE
OE, CE and WE Logic
CE
Address
Inputs
© 2020 Microchip Technology Inc.
Data Latch
Input/Output Buffers
Y-Gating
Y Decoder
X Decoder
Datasheet
Cell Matrix
Identification
DS20006352A-page 6
AT28HC256
Electrical Characteristics
4.
Electrical Characteristics
4.1
Absolute Maximum Ratings
Temperature under bias
-55°C to +125°C
Storage temperature
-65°C to +150°C
All input voltages (including NC pins) with respect to ground
-0.6V to +6.25V
All output voltages with respect to ground
-0.6V to VCC + 0.6V
Voltage on OE and A9 with respect to ground
-0.6V to +13.5V
Note: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device.
This is a stress rating only and functional operation of the device at these or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to absolute maximum rating conditions
for extended periods may affect device reliability.
4.2
DC and AC Operating Range
Table 4-1. DC and AC Operating Range
Operating Temperature (Case)
Military
AT28HC256‑90
AT28HC256‑12
-55°C to +125°C
-55°C to +125°C
5V ± 10%
5V ± 10%
Test Conditions
VCC Power Supply
4.3
DC Characteristics
Table 4-2. DC Characteristics
Parameter
Symbol
Minimum
Maximum
Units
Input Load Current
ILI
—
10
μA
VIN = 0V to VCC + 1V
Output Leakage Current
ILO
—
10
μA
VI/O = 0V to VCC
VCC Standby Current TTL
ISB1
—
3
mA
CE = 2.0V to VCC + 1V
VCC Standby Current CMOS
ISB2
—
300
μA
CE = VCC - 0.3V to VCC
VCC Active Current
ICC
—
80
mA
f = 5 MHz; IOUT = 0 mA
Input Low Voltage
VIL
—
0.8
V
Input High Voltage
VIH
2.0
—
V
Output Low Voltage
VOL
—
0.45
V
IOL = 6.0 mA
Output High Voltage
VOH1
2.4
—
V
IOH = -4 mA
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 7
AT28HC256
Electrical Characteristics
4.4
Pin Capacitance
Table 4-3. Pin Capacitance(1,2)
Symbol
Typical
Maximum
Units
Conditions
CIN
4
6
pF
VIN = 0V
COUT
8
12
pF
VOUT = 0V
Note:
1. This parameter is characterized but is not 100% tested in production.
2. f = 1 MHz, TA = 25°C
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 8
AT28HC256
Normalized ICC Graphics
Normalized ICC Graphics
Figure 5-1. Normalized Supply Current vs. Temperature
Normalized ICC
1.3
1.2
1.1
1.0
0.9
0.8
-55
-25
5
35
65
Temperature (°C)
95
125
Figure 5-2. Normalized Supply Current vs. Address Frequency
Normalized ICC
1.1
VCC = 5V
T = 25°C
1.0
0.9
0.8
0.7
0.6
0
2
4
6
Frequency (MHz)
8
10
Figure 5-3. Normalized Supply Current vs. Supply Voltage
1.4
Normalized ICC
5.
1.2
1.0
0.8
0.6
4.50
© 2020 Microchip Technology Inc.
5.00
5.25
4.75
Supply Voltage(V)
Datasheet
5.50
DS20006352A-page 9
AT28HC256
Device Operation
6.
Device Operation
READ: The AT28HC256 is accessed like a Static RAM. When CE and OE are low and WE is high, the data stored at
the memory location determined by the address pins is asserted on the outputs. The outputs are put in the highimpedance state when either CE or OE is high. This dual-line control gives designers flexibility in preventing bus
contention in their system.
BYTE WRITE: A low pulse on the WE or CE input with CE or WE low (respectively) and OE high initiates a write
cycle. The address is latched on the falling edge of CE or WE, whichever occurs last. The data is latched by the first
rising edge of CE or WE. Once a byte write is started, it will automatically time itself to completion. Once a
programming operation is initiated and for the duration of tWC, a read operation will effectively be a polling operation.
PAGE WRITE: The page write operation of the AT28HC256 allows 1 to 64 bytes of data to be written into the device
during a single internal programming period. A page write operation is initiated in the same manner as a byte write;
the first byte written can then be followed by 1 to 63 additional bytes. Each successive byte must be written within
150 µs (tBLC) of the previous byte. If the tBLC limit is exceeded, the AT28HC256 will cease accepting data and
commence the internal programming operation. All bytes during a page write operation must reside on the same
page as defined by the state of the A6‑A14 inputs. For each WE high‑to‑low transition during the page write
operation, A6‑A14 must be the same. The A0 to A5 inputs are used to specify which bytes within the page are to be
written. The bytes may be loaded in any order and may be altered within the same load period. Only bytes which are
specified for writing will be written; unnecessary cycling of other bytes within the page does not occur.
DATA POLLING: The AT28HC256 features DATA Polling to indicate the end of a write cycle. During a byte or page
write cycle, an attempted read of the last byte written will result in the complement of the written data to be presented
on I/O7. Once the write cycle has been completed, true data is valid on all outputs, and the next write cycle may
begin. DATA Polling may begin at any time during the write cycle.
TOGGLE BIT: In addition to DATA Polling, the AT28HC256 provides another method for determining the end of a
write cycle. During the write operation, successive attempts to read data from the device will result in I/O6 toggling
between one and zero. Once the write has completed, I/O6 will stop toggling and valid data will be read. Reading the
toggle bit may begin at any time during the write cycle.
DATA PROTECTION: If precautions are not taken, inadvertent writes may occur during transitions of the host system
power supply. Microchip incorporated both hardware and software features that will protect the memory against
inadvertent writes.
HARDWARE PROTECTION: Hardware features protect against inadvertent writes to the AT28HC256 in the following
ways:
• VCC sense – if VCC is below 3.8V (typical), the write function is inhibited
• VCC power‑on delay – once VCC has reached 3.8V, the device will automatically time out 5 ms (typical) before
allowing a write
• write inhibit – holding any one of OE low, CE high or WE high inhibits write cycles
• noise filter – pulses of less than 15 ns (typical) on the WE or CE inputs will not initiate a write cycle
SOFTWARE DATA PROTECTION: A software-controlled data protection feature has been implemented on the
AT28HC256. When enabled, the software data protection (SDP) will prevent inadvertent writes. The SDP feature may
be enabled or disabled by the user; the AT28HC256 is shipped with SDP disabled.
SDP is enabled by the host system issuing a series of three write commands; three specific bytes of data are written
to three specific addresses (refer to Software Data Protection Algorithm). After writing the 3‑byte command sequence
and after tWC, the entire AT28HC256 will be protected against inadvertent write operations. It should be noted that,
once protected, the host may still perform a byte or page write to the AT28HC256. This is done by preceding the data
to be written by the same 3‑byte command sequence used to enable SDP.
Once set, SDP will remain active unless the disable command sequence is issued. Power transitions do not disable
SDP and SDP will protect the AT28HC256 during power‑up and power‑down conditions. All command sequences
must conform to the page write timing specifications. The data in the enable and disable command sequences is not
written to the device and the memory addresses used in the sequence may be written with data in either a byte or
page write operation.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 10
AT28HC256
Device Operation
After setting SDP, any attempt to write to the device without the 3‑byte command sequence will start the internal write
timers. No data will be written to the device; however, for the duration of tWC, read operations will effectively be polling
operations.
DEVICE IDENTIFICATION: An extra 64 bytes of EEPROM memory are available to the user for device identification.
By raising A9 to 12V ± 0.5V and using address locations 7FC0H to 7FFFH, the bytes may be written to or read from
in the same manner as the regular memory array.
OPTIONAL CHIP ERASE MODE: The entire device can be erased using a 6‑byte software code. See Software Chip
Erase application note for details.
6.1
Operating Modes
Table 6-1. Operating Modes
Mode
CE
OE
WE
I/O
Read
VIL
VIL
VIH
DOUT
Write(1)
VIL
VIH
VIL
DIN
VIH
X(2)
X
High-Z
Write Inhibit
X
X
VIH
Write Inhibit
X
VIL
X
Output Disable
X
VIH
X
High-Z
VIL
VH(3)
VIL
High-Z
Standby/Write Inhibit
Chip Erase
Note:
1. Refer to AC Programming Waveforms.
2. X can be VIL or VH.
3. VH = 12.0 V ± 0.5V
6.2
AC Read Characteristics
Table 6-2. AC Read Characteristics
Parameter
Symbol
AT28HC256‑90
AT28HC256‑12
Units
Min.
Max.
Min.
Max.
tACC
—
90
—
120
ns
CE to Output Delay
tCE
(1)
—
90
—
120
ns
OE to Output Delay
tOE(2)
0
40
0
50
ns
0
40
0
50
ns
0
—
0
—
ns
Address to Output Delay
CE or OE to Output Float
Output Hold from OE or CE,
whichever occurred first
tDF
(3,4)
tOH
Note:
1. CE may be delayed up to tACC‑tCE after the address transition without impact on tACC.
2. OE may be delayed up to tCE‑tOE after the falling edge of CE without impact on tCE or by tACC‑tOE after an
address change without impact in tACC.
3. tDF is specified from OE or CE, whichever occurs first (CL = 5 pF).
4. This parameter is characterized and is not 100% tested.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 11
AT28HC256
Device Operation
6.3
AC Read Waveforms
ADDRESS VALID
ADDRESS
CE
tCE
tOE
OE
tOH
tACC
High-Z
OUTPUT
6.4
tDF
OUTPUT VALID
Input Test Waveforms and Measurement Level
3.0V
AC
DRIVING
LEVELS
AC
MEASUREMENT
LEVELS
1.5V
0.0V
Note: tR, tF < 5 ns.
6.5
Output Test Load
5.0V
1.8K
OUTPUT
PIN
1.3K
© 2020 Microchip Technology Inc.
100 pF
Datasheet
DS20006352A-page 12
AT28HC256
Device Operation
6.6
AC Write Characteristics
Table 6-3. AC Write Characteristics
Parameter
Symbol
Minimum
Maximum
Units
tAS, tOES
0
—
ns
Address Hold Time
tAH
50
—
ns
Chip Select Setup Time
tCS
0
—
ns
Chip Select Hold Time
tCH
0
—
ns
Write Pulse Width (WE or CE)
tWP
100
—
ns
Data Setup Time
tDS
50
—
ns
tDH, tOEH
0
—
µs
tDV
NR(1)
—
Address, OE Setup Time
Data, OE Hold Time
Time to Data Valid
Note:
1. NR = No Restriction
6.7
AC Write Waveforms
6.7.1
WE Controlled
OE
tOES
tOEH
ADDRESS
tAS
CE
tAH
tCH
tCS
WE
tWPH
tWP
tDV
tDS
tDH
DATA IN
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 13
AT28HC256
Device Operation
6.7.2
CE Controlled
OE
tOES
tOEH
ADDRESS
tAS
WE
tAH
tCH
tCS
CE
tWPH
tWP
tDV
tDH
tDS
DATA IN
6.8
Page Mode Characteristics
Table 6-4. Page Mode Characteristics
Parameter
Write Cycle Time
Symbol
AT28HC256
AT28HC256F
tWC
Minimum
Maximum
Units
—
10
ms
—
3
ms
Address Setup Time
tAS
0
—
ms
Address Hold Time
tAH
50
—
ns
Data Setup Time
tDS
50
—
ns
Data Hold Time
tDH
0
—
ns
Write Pulse Width
tWP
100
—
ns
Byte Load Cycle Time
tBLC
—
150
µs
Write Pulse Width High
tWPH
50
—
ns
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 14
AT28HC256
Device Operation
6.9
Page Mode Write Waveforms(1,2)
OE
CE
WE
A0-A14
tWPH
tWP
tAS
tBLC
tDH
tAH
VALID ADD
tDS
DATA
VALID DATA
BYTE 0
BYTE 1
BYTE 2
BYTE 62
BYTE 3
BYTE 63
tWC
Note:
1. A6 through A14 must specify the page address during each high-to-low transition of WE (or CE).
2. OE must be high only when WE and CE are both low.
6.10
Chip Erase Waveforms
VIH
CE
VIL
VH(3)
OE
VIH
tS(1)
tH
VIH
WE
VIL
tW(2)
Note:
1. tS = tH = 5 µsec (minimum)
2. tW = 10 msec (minimum)
3. VH = 12.0V ± 0.5V
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 15
AT28HC256
Device Operation
6.11
Software Data Protection Enable Algorithm(1)
LOAD DATA AA
TO
ADDRESS 5555
LOAD DATA 55
TO
ADDRESS 2AAA
LOAD DATA A0
TO
ADDRESS 5555
WRITES ENABLED(2)
LOAD DATA XX
TO
ANY ADDRESS(3)
LOAD LAST BYTE
TO
LAST ADDRESS
ENTER DATA
PROTECT STATE
Note:
1. Data format: I/O7-I/O0 (Hex); Address format: A14-A0 (Hex).
2. Write-Protect state will be activated at end of write even if no other data is loaded.
3. 1 to 64 bytes of data are loaded.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 16
AT28HC256
Device Operation
6.12
Software Data Protection Disable Algorithm(1)
LOAD DATA AA
TO
ADDRESS 5555
LOAD DATA 55
TO
ADDRESS 2AAA
LOAD DATA 80
TO
ADDRESS 5555
LOAD DATA AA
TO
ADDRESS 5555
LOAD DATA 55
TO
ADDRESS 2AAA
LOAD DATA 20
TO
ADDRESS 5555
EXIT DATA
PROTECT STATE(2)
LOAD DATA XX
TO
ANY ADDRESS(3)
LOAD LAST BYTE
TO
LAST ADDRESS
Note:
1. Data format: I/O7-I/O0 (Hex); Address format: A14-A0 (Hex).
2. Write-Protect state will be deactivated at end of write period even if no other data is loaded.
3. 1 to 64 bytes of data are loaded.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 17
AT28HC256
Device Operation
6.13
Software Protected Program Cycle Waveform(1,2)
OE
CE
tWPH
tWP
WE
tAS
tBLC
tAH
BYTE ADDRESS
A0-A5
A6-A14
tDS
tDH
PAGE ADDRESS
DATA
BYTE 0
BYTE 62
BYTE 63
tWC
Note:
1. A6-A14 must specify the same page address during each high-to-low transition of WE (or CE) after the
software code has been entered.
2. OE must be high only when WE and CE are both low.
6.14
Data Polling Characteristics(1)
Table 6-5. Data Polling Characteristics
Parameter
Symbol
Minimum
Typical
Maximum
Units
Data Hold Time
tDH
0
—
—
ns
OE Hold Time
tOEH
0
—
—
ns
OE to Output Delay(2)
tOE
—
—
—
ns
Write Recovery Time
tWR
0
—
—
ns
Note:
1. These parameters are characterized and not 100% tested.
2. See AC Read Characteristics.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 18
AT28HC256
Device Operation
6.15
Data Polling Waveforms
WE
CE
tOEH
OE
tDH
tOE
I/O7
6.16
High-Z
AN
A0-A14
tWR
AN
AN
AN
AN
Toggle Bit Characteristics(1)
Table 6-6. Toggle Bit Characteristics
Parameter
Symbol
Minimum
Typical
Maximum
Units
Data Hold Time
tDH
10
—
—
ns
OE Hold Time
tOEH
10
—
—
ns
OE to Output Delay(2)
tOE
—
—
—
ns
tOEHP
150
—
—
ns
tWR
0
—
—
ns
OE High
Pulse(2)
Write Recovery Time
Note:
1. These parameters are characterized and not 100% tested.
2. See AC Read Characteristics.
6.17
Toggle Bit Waveforms
WE
CE
tOEH
OE
tDH
I/O6
(2)
© 2020 Microchip Technology Inc.
tOE
High-Z
Datasheet
tWR
DS20006352A-page 19
AT28HC256
Device Operation
Note:
1. Toggling either OE or CE or both OE and CE will operate toggle bit.
2. Beginning and ending state of I/O6 will vary.
3. Any address location may be used but the address should not vary.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 20
AT28HC256
Packaging Information
7.
Packaging Information
7.1
Package Marking Information
AT28HC256: Package Marking Information (SMD devices)
28-pin CERDIP
Topside
32-pad CLCC
Backside
Δ
Topside
YWWNNN-19104S
1&&&&&&-$
YYWW
ATMEL
5962-88634
##XA C
AT28HC256@
%%DM/883
YQyywwl
Δ
ATMEL
5962-88634
##YA YQyywwl
AT28HC256@
%%LM/883 C
28-lead FLATPACK
Topside
Δ
## = SMD Device
03: 90ns, 10ms TWC
01: 120ns, 10ms TWC
04: 90ns, 3ms TWC
02: 120ns, 3ms TWC
YWWNNN-19104S
1&&&&&&-$
YYWW
%% = Access Time
90: 90 ns
12: 120 ns
YWWNNNS
19104
1&&&&&&-$
YYWW
30-pin PGA
Backside
ATMEL
5962-88634
##ZA C
AT28HC256@
%%FM/883
YQyywwl
Backside
Topside
Edges
ATMEL
5962-88634
##UA YQyywwl
AT28HC256@
%%UM/883 C
1&&&&&&-$ YYWW
Δ
YQNNNN-19104S
@ = Write Endurance Rating
Blank: Standard (10K at 10ms)
E: Extended (100K at 10ms)
F: Fast Write (10k at 3ms)
$ = Assembly Location
F: Philippines
N: Thailand
Country of Assembly
Lot Trace Code
Seal Year and Work Week
&&&&&&: Country of Assembly
YWWNNN: Lot Trace Code
YYWW: Seal Year and Work Week
Year, Quarter, Seal Year, Seal Week and Group D Coverage (Military Date Code)
YQyywwl: Year, Quarter, Seal Year, Seal Week and Group D Coverage (Military Date Code)
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 21
AT28HC256
Packaging Information
Dimensions in Millimeters and (Inches).
Controlling dimension: Inches.
MIL-STD 1835 D-10 Config A (Glass Sealed)
37.85(1.490)
36.58(1.440)
PIN
1
15.49(0.610)
12.95(0.510)
5.72(0.225)
MAX
33.02(1.300) REF
0.127(0.005)MIN
SEA TING
PLANE
5.08(0.200)
3.18(0.125)
2.54(0.100)BSC
1.52(0.060)
0.38(0.015)
0.66(0.026)
0.36(0.014)
1.65(0.065)
1.14(0.045)
15.70(0.620)
15.00(0.590)
0.46(0.018)
0.20(0.008)
0º~ 15º REF
17.80(0.700) MAX
10/23/03
TITLE
28D6, 28-lead, 0.600" Wide, Non-windowed,
Ceramic Dual Inline Package (Cerdip)
DRAWING NO.
28D6
REV.
B
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at http://
www.microchip.com/packaging.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 22
AT28HC256
Packaging Information
Dimensions in Millimeters and (Inches).
Controlling dimension: Inches.
MIL-STD 1835 F-12 Config B
9.40(0.370)
6.35(0.250)
PIN #1 ID
0.56(0.022)
0.38(0.015)
1.27(0.050) BSC
18.49(0.728)
18.08(0.712)
1.14(0.045) MAX
10.57(0.416)
9.75(0.384)
0.23(0.009)
0.10(0.004)
3.02(0.119)
2.29(0.090)
1.96(0.077)
1.09(0.043)
1.14(0.045)
0.660(0.026)
7.26(0.286)
6.96(0.274)
10/21/03
TITLE
28F, 28-lead, Non-windowed, Ceramic Bottom-brazed
Flat Package (FlatPack)
DRAWING NO.
28F
REV.
B
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at http://
www.microchip.com/packaging.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 23
AT28HC256
Packaging Information
Dimensions in Millimeters and (Inches).
Controlling dimension: Inches.
MIL-STD 1835 C-12
11.63(0.458)
11.23(0.442)
2.54(0.100)
2.16(0.085)
14.22(0.560)
13.72(0.540)
1.91(0.075)
1.40(0.055)
PIN 1
2.41(0.095)
1.91(0.075)
1.40(0.055)
1.14(0.045)
INDEX CORNER
0.635(0.025)
X 45°
0.381(0.015)
0.305(0.012)
RADIUS
0.178(0.007)
10.16(0.400) BSC
0.737(0.029)
0.533(0.021)
1.27(0.050) TYP
1.02(0.040) X 45°
7.62(0.300) BSC
2.16(0.085)
1.65(0.065)
10/21/03
TITLE
32L, 32-pad, Non-windowed, Ceramic Lid, Leadless Chip
Carrier (LCC)
DRAWING NO.
32L
REV.
B
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at http://
www.microchip.com/packaging.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 24
AT28HC256
Packaging Information
Dimensions in Millimeters and (Inches).
Controlling dimension: Inches.
7.26(0.286)
6.50(0.256)
13.74(0.540)
13.36(0.526)
2.57(0.101)
2.06(0.081)
15.24(0.600)
14.88(0.586)
1.40(0.055)
1.14(0.045)
0.58(0.023)
0.43(0.017)
3.12(0.123)
2.62(0.103)
1.83(0.072)
1.57(0.062)
14.17(0.558)
13.77(0.542)
2.54(0.100) TYP
16.71(0.658)
16.31(0.642)
12.70(0.500) TYP
2.54(0.100) TYP
10.41(0.410)
9.91(0.390)
10/21/03
TITLE
28U, 28-pin, Ceramic Pin Grid Array (PGA)
DRAWING NO.
28U
REV.
B
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at http://
www.microchip.com/packaging.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 25
AT28HC256
Revision History
8.
Revision History
Revision A (April 2020)
Updated to the Microchip template. Microchip DS20006352 replaces Atmel document 0006. Added updated Part
Markings to include new trace code format.
Atmel Document 0006 Revision M (December 2009)
Updated AC Characteristics and ordering information.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 26
AT28HC256
The Microchip Website
Microchip provides online support via our website at http://www.microchip.com/. This website is used to make files
and information easily available to customers. Some of the content available includes:
•
•
•
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 (FAQs), technical support requests, online
discussion groups, Microchip design partner 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
Product Change Notification Service
Microchip’s product change notification service helps keep customers current on Microchip products. Subscribers will
receive email notification whenever there are changes, updates, revisions or errata related to a specified product
family or development tool of interest.
To register, go to http://www.microchip.com/pcn and follow the registration instructions.
Customer Support
Users of Microchip products can receive assistance through several channels:
•
•
•
•
Distributor or Representative
Local Sales Office
Embedded Solutions Engineer (ESE)
Technical Support
Customers should contact their distributor, representative or ESE for support. Local sales offices are also available to
help customers. A listing of sales offices and locations is included in this document.
Technical support is available through the website at: http://www.microchip.com/support
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 27
AT28HC256
Product Identification System
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
AT28 HC 256 (E) - 12 D M /883
/883 = MIL-STD-883 Class B Product
AT28 = Parallel EEPROM
M = -55°C to +125°C Military Temperature Grade, Sn63/Pb37 Terminal Finish
C = 4.5V to 5.5V
256 = 256 Kbit Size
Blank = 10K Standard Write Endurance
E = 100K Extended Write Endurance Option
F = 3 ms Fast Write Option
D = 28-Lead, 600 mil Wide, Non-Windowed, Ceramic Dual Inline (Cerdip)
L = 32-Pad, Non-Windowed, Combo Lid, Leadless Chip Carrier (CLCC)
F = 28-Lead, Non-Windowed, Ceramic Bottom-Brazed Flat Package (Flatpack)
U = 30-Pin, Ceramic Pin Grid Array (PGA)
12 = 120 ns Speed
90 = 90 ns Speed
WM = Die Sales (contact Microchip)
DWFM = Wfer Sales (contact Microhip)
Examples
Table 12-1. AT28HC256 Ordering Information
Ordering Code
Standard Military
Drawing Number (SMD#)
Package
Number
AT28HC256-90DM/883
5962‑88634 03 XA
28D6
AT28HC256-90FM/883
5962‑88634 03 ZA
28F
AT28HC256-90LM/883
5962‑88634 03 YA
32L
AT28HC256-90UM/883
5962‑88634 03 UA
28U
AT28HC256-12DM/883
5962‑88634 01 XA
28D6
AT28HC256-12FM/883
5962‑88634 01 ZA
28F
AT28HC256-12LM/883
5962‑88634 01 YA
32L
AT28HC256-12UM/883
5962‑88634 01 UA
28U
© 2020 Microchip Technology Inc.
Datasheet
tACC(ns)
Operating Range
90
Military/883C Class B,
Fully Compliant
(-55°C to 125°C)
120
DS20006352A-page 28
AT28HC256
Table 12-2. AT28HC256E Ordering Information (Not Dual Marked Packages)
Ordering Code
Standard Military
Drawing Number (SMD#)
Package
Number
AT28HC256E‑90DM/883
N/A
28D6
AT28HC256E‑90FM/883
N/A
28F
AT28HC256E‑90LM/883
N/A
32L
AT28HC256E‑90UM/883
N/A
28U
AT28HC256E‑12DM/883
N/A
28D6
AT28HC256E‑12FM/883
N/A
28F
AT28HC256E‑12LM/883
N/A
32L
AT28HC256E‑12UM/883
N/A
28U
tACC(ns)
Operating Range
90
Military/883C Class B,
Fully Compliant
(-55°C to 125°C)
120
Table 12-3. AT28HC256F Ordering Information
Ordering Code
Standard Military
Drawing Number (SMD#)
Package
Number
AT28HC256F‑90DM/883
5962‑88634 04 XA
28D6
AT28HC256F‑90FM/883
5962‑88634 04 ZA
28F
AT28HC256F‑90LM/883
5962‑88634 04 YA
32L
AT28HC256F‑90UM/883
5962‑88634 04 UA
28U
AT28HC256F‑12DM/883
5962‑88634 02 XA
28D6
AT28HC256F‑12FM/883
5962‑88634 02 ZA
28F
AT28HC256F‑12LM/883
5962‑88634 02 YA
32L
AT28HC256F‑12UM/883
5962‑88634 02 UA
28U
tACC(ns)
Operating Range
90
Military/883C Class B,
Fully Compliant
(-55°C to 125°C)
120
Package Types
28D6
28-Lead, 0.600" Wide, Non-Windowed, Ceramic Dual Inline (Cerdip)
28F
28-Lead, Non-Windowed, Ceramic Bottom-Brazed Flat Package (Flatpack)
32L
32-Pad, Non-Windowed, Ceramic Leadless Chip Carrier (LCC)
28U
28-Pin, Ceramic Pin Grid Array (PGA)
WM
Diced Die Military
DWFM
Die in Wafer Form Military
Options
Blank
Standard Device: Endurance = 10K Write Cycles; Write Time 10 ms
E
High Endurance Option: Endurance = 100K Write Cycles
F
Fast Write Option: Write Time = 3 ms
Microchip Devices Code Protection Feature
Note the following details of the code protection feature on Microchip devices:
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 29
AT28HC256
•
•
•
•
•
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.
Legal Notice
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 unless
otherwise stated.
Trademarks
The Microchip name and logo, the Microchip logo, Adaptec, AnyRate, AVR, AVR logo, AVR Freaks, BesTime,
BitCloud, chipKIT, chipKIT logo, CryptoMemory, CryptoRF, dsPIC, FlashFlex, flexPWR, HELDO, IGLOO, JukeBlox,
KeeLoq, Kleer, LANCheck, LinkMD, maXStylus, maXTouch, MediaLB, megaAVR, Microsemi, Microsemi logo, MOST,
MOST logo, MPLAB, OptoLyzer, PackeTime, PIC, picoPower, PICSTART, PIC32 logo, PolarFire, Prochip Designer,
QTouch, SAM-BA, SenGenuity, SpyNIC, SST, SST Logo, SuperFlash, Symmetricom, SyncServer, Tachyon,
TempTrackr, TimeSource, tinyAVR, UNI/O, Vectron, and XMEGA are registered trademarks of Microchip Technology
Incorporated in the U.S.A. and other countries.
APT, ClockWorks, The Embedded Control Solutions Company, EtherSynch, FlashTec, Hyper Speed Control,
HyperLight Load, IntelliMOS, Libero, motorBench, mTouch, Powermite 3, Precision Edge, ProASIC, ProASIC Plus,
ProASIC Plus logo, Quiet-Wire, SmartFusion, SyncWorld, Temux, TimeCesium, TimeHub, TimePictra, TimeProvider,
Vite, WinPath, and ZL are registered trademarks of Microchip Technology Incorporated in the U.S.A.
Adjacent Key Suppression, AKS, Analog-for-the-Digital Age, Any Capacitor, AnyIn, AnyOut, BlueSky, BodyCom,
CodeGuard, CryptoAuthentication, CryptoAutomotive, CryptoCompanion, CryptoController, dsPICDEM,
dsPICDEM.net, Dynamic Average Matching, DAM, ECAN, EtherGREEN, In-Circuit Serial Programming, ICSP,
INICnet, Inter-Chip Connectivity, JitterBlocker, KleerNet, KleerNet logo, memBrain, Mindi, MiWi, MPASM, MPF,
MPLAB Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach, Omniscient Code Generation, PICDEM,
PICDEM.net, PICkit, PICtail, PowerSmart, PureSilicon, QMatrix, REAL ICE, Ripple Blocker, SAM-ICE, Serial Quad
I/O, SMART-I.S., SQI, SuperSwitcher, SuperSwitcher II, Total Endurance, TSHARC, USBCheck, VariSense,
ViewSpan, WiperLock, Wireless DNA, 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.
The Adaptec logo, Frequency on Demand, Silicon Storage Technology, and Symmcom are registered trademarks of
Microchip Technology Inc. in other countries.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 30
AT28HC256
GestIC is a registered trademark of Microchip Technology Germany II GmbH & Co. KG, a subsidiary of Microchip
Technology Inc., in other countries.
All other trademarks mentioned herein are property of their respective companies.
©
2020, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved.
ISBN: 978-1-5224-6095-4
AMBA, Arm, Arm7, Arm7TDMI, Arm9, Arm11, Artisan, big.LITTLE, Cordio, CoreLink, CoreSight, Cortex, DesignStart,
DynamIQ, Jazelle, Keil, Mali, Mbed, Mbed Enabled, NEON, POP, RealView, SecurCore, Socrates, Thumb,
TrustZone, ULINK, ULINK2, ULINK-ME, ULINK-PLUS, ULINKpro, µVision, Versatile are trademarks or registered
trademarks of Arm Limited (or its subsidiaries) in the US and/or elsewhere.
Quality Management System
For information regarding Microchip’s Quality Management Systems, please visit http://www.microchip.com/quality.
© 2020 Microchip Technology Inc.
Datasheet
DS20006352A-page 31
Worldwide Sales and Service
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Datasheet
DS20006352A-page 32