UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
1
Austin Semiconductor, Inc.
FEATURES
Organized 32,768 x 8
Single +5V ±10% power supply
Pin-compatible with existing 256K ROM’ s and EPROM’ s
All inputs/outputs fully TTL compatible
Power-saving CMOS technology
Very high-speed FLASHRITE Pulse Programming
3-state output buffers
400-mV DC assured noise immunity with standard TTL
loads
Latchup immunity of 250 mA on all input and output pins
Low power dissipation (CMOS Input Levels)
-Active - 165mW Worst Case
-Standby - 1.7mW Worst Case (CMOS-input levels)
* FUTURE High Speed Offerings: 55ns, 70ns, 90ns
OPTIONS MARKING
Timing
120ns access -12
150ns access -15
170ns access -17
200ns access -20
250ns access -25
300ns access -30
55ns access -55
70ns access -70
90ns access -90
Package(s)
Ceramic DIP (600mils) J No. 110
Ceramic LCC (450 x 550 mils) ECA No. 208
Processing / Operating T emperatur e Ranges
Full Military (-55oC to +125oC) M
Industrial (-40°C to +85°C) I
Military Temp (-55oC to +125oC) XT
PIN ASSIGNMENT
(Top View)
AVAILABLE AS MILITARY
SPECIFICATIONS
• -55C to 125C operation
• MILIT AR Y Processing Method MIL-PRF-38535, Class Q
• Commercial Version A vailable
28-Pin DIP (J)
(600 MIL)
256K UVEPROM
UV Erasable Programmable
Read-Only Memory
For more products and information
please visit our web site at
www.austinsemiconductor.com
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
VPP
A12
A7
A6
A5
A4
A3
A2
A1
A0
DQ0
DQ1
DQ2
GND
Vcc
A14
A13
A8
A9
A11
G\
A10
E\
DQ7
DQ6
DQ5
DQ4
DQ3
32-Pin LCC (ECA)
(450 x 550 mils)
Pin Name Function
4 3 2 1 32 31 30
A12
A14
A10
NC
V
CC
A15
CE2
14 15 16 17 18 19 20
DQ2
DQ3
V
SS
DQ4
DQ5
DQ6
DQ7
5
6
7
8
9
10
11
12
13
A7
A6
A5
A4
A3
A2
A1
A0
DQ1
29
28
27
26
25
24
23
22
21
WE
A13
A8
A9
A11
OE
A10
CE1
DQ8
\
\
6
\
A7
A12
V
PP
NC
V
CC
A14
A13
A6
A5
A4
A3
A2
A1
A0
NC
DQ0
DQ1
DQ2
GND
NC
DQ3
DQ4
DQ5
A8
A9
A11
NC
G\
A10
E\
DQ7
DQ6
Pin Name Function
A0 - A14 Address Inputs
DQ0-DQ7 Inputs (programming)/Outputs
E\ Chip Enable/Power Down
G\ Output Enable
GND Ground
V
CC
5V Supply
V
PP
13V Programming Power Supply
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
2
Austin Semiconductor, Inc.
GENERAL DESCRIPTION
The AS27C256 series is a set of 262,144 bit, ultraviolet-light
erasable, electrically programmable read-only memories.
These devices are fabricated using power-saving CMOS tech-
nology for high speed and simple interface with MOS and bipo-
lar circuits. All inputs (including program data inputs) can be
driven by Series 54 TTL circuits without the use of external
pullup resistors. Each output can drive one Series 54 TTL
circuit without external resistors. The data outputs are 3-state
for connecting multiple devices to a common bus. The
AS27C256 is pin-compatible with 28-pin 256K ROMs and
EPROMs. It is offered in a 600mil dual-in-line ceramic package
(J suffix) and a 450 x 550 mil ceramic LCC (ECA suffix) rated for
operation from -55°C to 125°C.
Because this EPROM operates from a single 5V supply (in
the read mode), it is ideal for use in microprocessor-based sys-
tems. One other supply (12.75V) is needed for programming.
All programming signals are TTL level. This device is pro-
grammable by the AMD FLASHRITE Pulse programming algo-
rithm. The FLASHRITE Pulse programming algorithm uses a
VPP of 12.75VV and a VCC of 6.25V for a nominal programming
time of four seconds. For programming outside the system,
existing EPROM programmers can be used. Locations can be
programmed singly , in blocks, or at random.
FUNCTIONAL BLOCK DIAGRAM*
* This symbol is in accordance with ANSI/IEEE std 91-1984 and IEC Publication 617-12.
A0
A1
A2
A3
A4
A5 DQ0
A6 DQ1
A7 DQ2
A8 DQ3
A9 DQ4
A10 DQ5
A11 DQ6
A12 DQ7
A13
A14
E\
G\ &
10
[PWR DWN]
9
8
7
6
5
4
3
25
24
21
23
2
26
27
20
22 EN
A
A
A
A
A
A
A
A
11
12
13
15
16
17
18
19
EPROM 32,768 x 8
0
14
A0
32,767
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
3
Austin Semiconductor, Inc.
OPERATION
The seven modes of operation for the AS27C256 are listed in Table 1. The read mode requires a single 5V supply.
All inputs are TTL level except for VPP during programming (12.75V for FLASHRITE Pulse), and (12V) on A9
for signature mode.
TABLE 1. OPERATION MODES
NOTES:
* X can be VIL or VIH
** Die is AMD. User can program on benchtop programmer by selecting AM27C256 from the device
type selection menu.
READ OUTPUT
DISABLE STANDBY PROGRAMMING VERIFY PROGRAM
INHIBIT
E\ VIL VIL VIH VIL VIH VIH
G\ VIL VIH XVIH VIL X
VPP X
1
X
1
X
1
VPP VPP VPP
VCC VCC VCC VCC+/-.3V VCC VCC VCC
A9 X X X X X X VID
2VID
2
A0 X X X X X X VIL VIH
MFG DEVICE
01h 10h
1
For normal standby & read operation, VPP is Don't Care X.
2
V
ID
= 12V +/- .5V
Data OutData Out High-Z High-Z Data In High-Z
VCC
FUNCTION
(PINS) SIGNATURE MODE
MODE*
CODE**
DQ0-DQ7
VCC
VIL
VIL
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
4
Austin Semiconductor, Inc.
READ/OUTPUT DISABLE
When the outputs of two or more AS27C256 are connected in
parallel on the same bus, the output of any particular device in
the circuit can be read with no interference from the compet-
ing outputs of the other devices. To read the output of the
selected AS27C256, a low-level signal is applied to E\ and G\.
All other devices in the circuit should have their outputs
disabled by applying a high-level signal to one of these pins.
Output data is accessed at pins DQ0 through DQ7.
LA TCHUP IMMUNITY
Latchup immunity on the AS27C256 is a minimum of 250mA on
all inputs and outputs. This feature provides latchup im-
munity beyond any potential transients at the printed cir-
cuit board level when the EPROM is interfaced to industry
standard TTL or MOS logic devices. Input/output layout
approach controls latchup without compromising performance
or packing density.
POWER DOWN
Active ICC supply current can be reduced from 25mA (AS27C256-
12 through AS27C256-25) to 1mA (TTL-level inputs) or 300µA
(CMOS-level inputs) by applying a high TTL/CMOS signal to
the E\ pin. In this mode all outputs are in the high-impedance
state.
ERASURE
Before programming, the AS27C256 is erased by exposing the
chip through the transparent lid to a high-intensity ultraviolet
light (wavelength 2537 Å). EPROM erasure before program-
ming is necessary to ensure that all bits are in the logic-high
state. Logic-lows are programmed into the desired locations. A
programmed logic-low can be erased only by ultraviolet light.
The recommended minimum exposure dose (UV intensity x ex-
posure time) is 15W•s/cm2. A typical 12mW/cm2, filterless UV
lamp erases the device in 21 minutes. The lamp should be
located about 2.5cm above the chip during erasure. After era-
sure, all bits are in the high state. It should be noted that normal
ambient light contains the correct wavelength for erasure; there-
fore, when using the AS27C256, the window should be covered
with an opaque label.
FLASHRITE PULSE PROGRAMMING
The AS27C256 EPROM is programmed by using the AMD
FLASHRITE Pulse programming algorithm as illustrated by the
flowchart in Figure 1. This algorithm programs the device in a
nominal time of 4 seconds. Actual programming time varies as
a function of the programmer used.
Data is presented in parallel (eight bits) on pins DQ0 to DQ7.
Once addresses and data are stable, E\ is pulsed.
The FLASHRITE Pulse programming algorithm uses initial
pulses of 100 microseconds (µs) followed by a byte-verifica-
tion step to determine when the addressed byte has been suc-
cessfully programmed. Up to 25 100µs pulses per byte are
provided before a failure is recognized.
The programming mode is achieved when VPP = 12.75V,
VCC= 6.25V, G\ = VIH, and E\ = VIL. More than one device can be
programmed when the devices are connected in parallel. Loca-
tions can be programmed in any order. When the AMD
FLASHRITE Pulse programming routine is completed, all bits
are verified with VCC = VPP = 5V.
PROGRAM INHIBIT
Programming can be inhibited by maintaining a high-level
input on E\.
PROGRAM VERIFY
Programmed bits can be verified with VPP = 12.75V when G\ =
VIL, and E\ = VIH.
SIGNA TURE MODE
The signature mode provides access to a binary code iden-
tifying the manufacturer and device type. This mode is acti-
vated when A9 is forced to 12V ±0.5V. T wo identifier bytes are
accessed by A0 (terminal 10); i.e., A0=VIL accesses the manu-
facturer code, which is output on DQ0-DQ7; A0=VIH accesses
the device code, which is also output on DQ0-DQ7. All other
addresses must be held at VIL. Each byte contains odd parity
on bit DQ7. The manufacturer code for these devices is 01h
and the device code is 10h.
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
5
Austin Semiconductor, Inc.
FIGURE 1. FLASHRITE PULSE PROGRAMMING FLOWCHART
Start
Address = First Location
VCC=6.25V, VPP=12.75V
X = 0
Program One 100us Pulse
Increment X
Programming
Section X = 25 ? YES
NO
Program
FAI L Verify
Byte?
Pass
Last
Increment Address NO Address?
Yes
VCC = VPP = 5.25V
Read READ
Verify Verify FAIL Device Failed
Section Bytes?
Pass
Device Passed
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
6
Austin Semiconductor, Inc.
*Stresses greater than 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 section of this specification is not implied. Expo-
sure to absolute maximum rating conditions for extended peri-
ods may affect reliability .
** All voltage values are with respect to GND.
ABSOLUTE MAXIMUM RA TINGS*
Supply Voltage Range, VCC**...........................-0.6V to +7.0V
Supply Voltage Range, Vpp**...............................-0.6V to +13.5V
Input Voltage Range, All inputs except A9**..-0.6V to +6.0V
A9.....-0.6V to +13.5V
Output Voltage Range**...............................-0.6V to VCC +.6V
Minimum Operating Free-air T emperature, TA..............-55°C
Maximum Operating Case T emperature, TC...................125°C
Storage T emperature Range, Tstg.....................-65°C to 150°C
RECOMMENDED OPERATING CONDITIONS
NOTES:
1. VCC must be applied before or at the same time as VPP and removed after or at the same time as VPP. The deivce must not be inserted into or
removed from the board when VPP or VCC is applied.
2. VPP can be connected to VCC directly (except in the program mode). VCC supply current in this case would be ICC2 + IPP1.
ELECTRICAL CHARACTERISTICS OVER RECOMMENDED RANGES OF SUPPLY VOLTAGE
AND OPERATING FREE-AIR TEMPERATURE
NOTES:
1. Typical values are at TA=25°C and nominal voltages.
2. This parameter has been characterized at 25°C and is not tested.
TEST CONDITIONS MIN TYP1MAX UNIT
VOH IOH = -400µA 2.4 V
VOL IOL = 2.1mA 0.4 V
IIVI = 0V to 5.5V ±1 µA
IOVO = 0V to VCC ±5 µA
IPP1 VPP = VCC = 5.5V 100 µA
IPP2 VPP = 13V 30 50 mA
TTL-Input Level VCC = 5.5V, E\=VIH 1mA
CMOS-Input Level VCC = 5.5V, E\=VCC 300 µA
ICC2 VCC supply current (active)
'27C256-12
'27C256-15
'27C256-17
'27C256-20,-25
E\=VIL, VCC=5.5V
tcycle = minimum, outputs
open
15 25 mA
PARAMETER
ICC1 VCC supply current (standby)
High-level output voltage
Low-level output voltage
Input current (leakage)
VPP supply current
Output current (leakage)
VPP supply current (during program pulse)2
MIN TYP MAX
4.5 5 5.5
6 6.25 6.5
V
CC
-0.6
12.5 12.75 13
TTL inputs 2.2 V
CC
+.6
CMOS inputs V
CC
-0.2 V
CC
+.6
TTL inputs -0.5 0.8
CMOS inputs -0.5 0.2
V
ID
11.5 12 12.5
T
A
-55
T
C
+125
V
CC
Read Mode
1
FLASHRITE Pulse programming algorithm
Supply Voltage
Read Mode
2
FLASHRITE Pulse programming algorithm
V
PP
High-level input voltage
V
IH
Supply Voltage
V
IL
Low-level input voltage
Operating free-air temperature
Operating case temperature
Voltage level on A9 for signature mode
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
7
Austin Semiconductor, Inc.
NOTES:
1.Timing measurements are made at 2V for logic high and 0.8V for logic low (see figure 2).
2. Common test conditions apply for tdis except during programming.
3. Value calculated from 0.5V delta to measured output level. This parameter is only sampled and not 100% tested.
SWITCHING CHARACTERISTICS FOR PROGRAMMING: VCC = 6.5V and VPP = 12.75V (AMD
FLASHRITE ALGO), TA = 25°C
CAPACITANCE OVER RECOMMENDED RANGES OF SUPPLY VOLTAGE AND OPERAT-
ING FREE-AIR TEMPERATURE, f = 1MHz*
* Capacitance measurements are made on a sample basis only.
** Typical values are at TA = 25°C and nominal voltages.
SWITCHING CHARACTERISTICS OVER RECOMMENDED RANGES OF SUPPLY VOLT-
AGE AND OPERATING FREE-AIR TEMPERATURE1,2
TEST CONDITIONS TYP** MAX UNIT
C
i
Input capacitance V
I
= 0V 610pF
C
o
Output capacitance V
O
= 0V 10 14 pF
PARAMETER
MIN MAX MIN MAX
ta(A) Access time from address 120 150 ns
ta(E) Access time from E\ 120 150 ns
ten(G)R Output enable time from G\ 40 50 ns
tdis
Disable time of output from G\ or E\,
whichever occurs first30 30 0 30 ns
tv(A)
Output data valid time after change of
address, E\, or G\, whichever occurs first300 ns
PARAMETER -12
see Figure 2
-15 UNIT
TEST
CONDITIONS1, 2
MIN MAX MIN MAX MIN MAX
t
a(A)
Access time from address 170 200 250 ns
t
a(E)
Access time from E\ 170 200 250 ns
t
en(G)R
Output enable time from G\ 50 60 60 ns
t
dis
Disable time of output from G\ or E\,
whichever occurs first
3
040050060 ns
t
v(A)
Output data valid time after change of
address, E\, or G\, whichever occurs first
3
000 ns
see Figure 2
-25 UNIT
TEST
CONDITIONS
1, 2
PARAMETER -17 -20
MIN MAX UNIT
t
dis(G)
Output disable time from G\ 0 130 ns
t
en(G)W
Output enable time from G\ 150 ns
PARAMETER
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
8
Austin Semiconductor, Inc.
RECOMMENDED TIMING REQUIREMENTS FOR PROGRAMMING: VCC = 6.5 and VPP =
12.75V (AMD FLASHRITE ALGO), TA = 25°C (See Figure 2)
PARAMETER MEASUREMENT INFORMATION
NOTES:
1. CL includes probe and fixture capacitance.
FIGURE 2. LOAD CIRCUIT AND VOLTAGE WAVEFORMS
The AC testing inputs are driven at 2.4V for logic high and 0.4V for logic low . Timing measurements are made
at 2V for logic high and 0.8V for logic low for both inputs and outputs.
2.08V
Output Under Test
RL = 800
CL = 100 pF1
MIN TYP MAX UNIT
th(A) s
th(D) s
tw(E)PR 95 100 105 µs
tsu(A) s
tsu(G) s
tsu(E) s
tsu(D) s
tsu(VPP) s
tsu(VCC) s
Hold Time, Address
Hold Time, Data
Setup Time, Address
Pulse Duration, Initial Program
Setup Time, VCC
Setup Time, G\
Setup Time, E\
Setup Time, Data
Setup Time, VPP
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
9
Austin Semiconductor, Inc.
FIGURE 3. READ-CYCLE TIMING
FIGURE 4. PROGRAM-CYCLE TIMING (FLASHRITE PULSE PROGRAMMING)
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
10
Austin Semiconductor, Inc.
MECHANICAL DEFINITION*
*All measurements are in inches.
ASI Case #110 (Package Designator J)
eA c
D
E
S2 A
Q
L
eb
b2
S1
Symbol
SMD Specifications
MIN MAX
A --- 0.232
b 0.014 0.026
b2 0.045 0.065
c 0.008 0.018
D --- 1.490
E 0.500 0.610
eA 0.600 BSC
e 0.100 BSC
L 0.125 0.200
Q 0.015 0.060
S1 0.005 ---
S2 0.005 ---
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
11
Austin Semiconductor, Inc.
ASI Case #208 (Package Designator ECA)
MECHANICAL DEFINITIONS*
*All measurements are in inches.
b1
Detail A
E1
L1
b
D1
L
See Detail A
e
E
D
A
MIN MAX
A 0.060 0.120
b 0.022 0.028
b1 0.006 0.022
D 0.442 0.458
D1
E 0.540 0.560
E1
e
L 0.045 0.055
L1 0.075 0.095
0.050 BSC
SYMBOL
SMD SPECIFICATIONS
0.300 BSC
0.400 BSC
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
12
Austin Semiconductor, Inc.
*PROCESS / OPERATING TEMPERATURE
M = Full Military Processing Per -55oC to +125oC
MIL-PRF-3835, Class Q
I = Industrial T emperature Range -40°C to +85°C
XT = Military Temperature Range -55oC to +125oC
EXAMPLE: AS27C256-30JM/MIL
Device Number Speed Package Type Operating Temp.
AS27C256 -55 J *
AS27C256 -70 J *
AS27C256 -90 J *
AS27C256 -12 J *
AS27C256 -15 J *
AS27C256 -17 J *
AS27C256 -20 J *
AS27C256 -25 J *
AS27C256 -30 J *
EXAMPLE: AS27C256-15ECAM
Device Number Speed Package Type Operating Temp.
AS27C256 -55 E C A *
AS27C256 -70 E C A *
AS27C256 -90 E C A *
AS27C256 -12 E C A *
AS27C256 -15 E C A *
AS27C256 -17 E C A *
AS27C256 -20 E C A *
AS27C256 -25 E C A *
AS27C256 -30 E C A *
ORDERING INFORMA TION
UVEPROMUVEPROM
UVEPROMUVEPROM
UVEPROM
AS27C256
AS27C256
Rev. 2.0 7/06 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
13
Austin Semiconductor, Inc.
SMD ORDERING INFORMATION
SMD ASI PN SPEED PACKAG
E
5962-8606301XA AS27C256 -20JM 200ns 600mil, 28LD. DIP
5962-8606311XA AS27C256 -20JM 200ns 600mil, 28LD. DIP
5962-8606302XA AS27C256 -25JM 250ns 600mil, 28LD. DIP
5962-8606312XA AS27C256 -25JM 250ns 600mil, 28LD. DIP
5962-8606303XA AS27C256 -30JM 300ns 600mil, 28LD. DIP
5962-8606313XA AS27C256 -30JM 300ns 600mil, 28LD. DIP
5962-8606304XA AS27C256 -17JM 170ns 600mil, 28LD. DIP
5962-8606314XA AS27C256 -17JM 170ns 600mil, 28LD. DIP
5962-8606305XA AS27C256 -15JM 150ns 600mil, 28LD. DIP
5962-8606315XA AS27C256 -15JM 150ns 600mil, 28LD. DIP
5962-8606306XA AS27C256 -12JM 120ns 600mil, 28LD. DIP
5962-8606316XA AS27C256 -12JM 120ns 600mil, 28LD. DIP
5962-8606307XA AS27C256 -90JM 90ns 600mil, 28LD. DIP
5962-8606317XA AS27C256 -90JM 90ns 600mil, 28LD. DIP
5962-8606308XA AS27C256 -70JM 70ns 600mil, 28LD. DIP
5962-8606318XA AS27C256 -70JM 70ns 600mil, 28LD. DIP
5962-8606309XA AS27C256 -55JM 55ns 600mil, 28LD. DIP
5962-8606319XA AS27C256 -55JM 55ns 600mil, 28LD. DIP
SMD ASI PN SPEED PACKAG
E
5962-8606301YA AS27C256 -20ECA 200ns 32-LD. 0.450 x 0.550, LCC
5962-8606311YA AS27C256 -20ECA 200ns 32-LD. 0.450 x 0.550, LCC
5962-8606302YA AS27C256 -25ECA 250ns 32-LD. 0.450 x 0.550, LCC
5962-8606312YA AS27C256 -25ECA 250ns 32-LD. 0.450 x 0.550, LCC
5962-8606303YA AS27C256 -30ECA 300ns 32-LD. 0.450 x 0.550, LCC
5962-8606313YA AS27C256 -30ECA 300ns 32-LD. 0.450 x 0.550, LCC
5962-8606304YA AS27C256 -17ECA 170ns 32-LD. 0.450 x 0.550, LCC
5962-8606314YA AS27C256 -17ECA 170ns 32-LD. 0.450 x 0.550, LCC
5962-8606305YA AS27C256 -15ECA 150ns 32-LD. 0.450 x 0.550, LCC
5962-8606315YA AS27C256 -15ECA 150ns 32-LD. 0.450 x 0.550, LCC
5962-8606306YA AS27C256 -12ECA 120ns 32-LD. 0.450 x 0.550, LCC
5962-8606316YA AS27C256 -12ECA 120ns 32-LD. 0.450 x 0.550, LCC
5962-8606307YA AS27C256 -90ECA 90ns 32-LD. 0.450 x 0.550, LCC
5962-8606317YA AS27C256 -90ECA 90ns 32-LD. 0.450 x 0.550, LCC
5962-8606308YA AS27C256 -70ECA 70ns 32-LD. 0.450 x 0.550, LCC
5962-8606318YA AS27C256 -70ECA 70ns 32-LD. 0.450 x 0.550, LCC
5962-8606309YA AS27C256 -55ECA 55ns 32-LD. 0.450 x 0.550, LCC
5962-8606319YA AS27C256 -55ECA 55ns 32-LD. 0.450 x 0.550, LCC