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W27E257 32K x 8 ELECTRICALLY ERASABLE EPROM
GENERAL DESCRIPTION
The W27E257 is a high-speed, low-power Electrically Erasable and Programmable Read Only Memory organized as 32768 x 8 bits that operates on a single 5 volt power supply. The W27E257 provides an electrical chip erase function. This part was the same EPROM Writer's utilities as the W27E256.
FEATURES
* High speed access time: * * * *
100/120/150 nS (max.) Read operating current: 15 mA (typ.) Erase/Programming operating current 1 mA (typ.) Standby current: 5 A (typ.) Single 5V power supply
* +14V erase/+12V programming voltage * Fully static operation * All inputs and outputs directly TTL/CMOS
compatible
* Three-state outputs * Available packages: 28-pin 600 mil DIP and
32-pin PLCC
PIN CONFIGURATIONS
VPP A12 A7 A6 A5 A4 A3 A2 A1 A0 Q0 Q1 Q2 GND 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28-pin DIP 28 27 26 25 24 23 22 21 20 19 18 17 16 15 VCC A14 A13 A8 A9 A11 OE A10 CE Q7 Q6 Q5 Q4 Q3
BLOCK DIAGRAM
Q0 . . Q7
CE OE
CONTROL
OUTPUT BUFFER
A0 . . A14 VCC GND VPP
DECODER
CORE ARRAY
AV VAA A1PNC11 72PCC43 432 A6 A5 A4 A3 A2 A1 A0 NC Q0 5 6 7 8 9 10 11 12 1 13 4 1 3 2 3 1 3 0 29 28 27 26 25 24 23 22 2 0 21
PIN DESCRIPTION
A8 A9 A11 NC OE A10 CE Q7 Q6
SYMBOL A0-A14 Q0-Q7 CE OE VPP VCC GND NC
32-pin PLCC
1 5
1 6
11 78
1 9
Q QGN 1 2NC D
QQQ 345
DESCRIPTION Address Inputs Data Inputs/Outputs Chip Enable Output Enable Program/Erase Supply Voltage Power Supply Ground No Connection Publication Release Date: January 1997 Revision A3
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W27E257
FUNCTIONAL DESCRIPTION
Read Mode
Like conventional UVEPROMs, the W27E257 has two control functions, both of which produce data at the outputs. CE is for power control and chip select. OE controls the output buffer to gate data to the output pins. When addresses are stable, the address access time (TACC) is equal to the delay from CE to output (TCE), and data are available at the outputs TOE after the falling edge of OE, if TACC and TCE timings are met.
Erase Mode
The erase operation is the only way to change data from "0" to "1." Unlike conventional UVEPROMs, which use ultraviolet light to erase the contents of the entire chip (a procedure that requires up to half an hour), the W27E257 uses electrical erasure. Generally, the chip can be erased within 100 mS by using an EPROM writer with a special erase algorithm. Erase mode is entered when VPP is raised to VPE (14V), VCC = VCE (5V), OE = VIH (2V or above but lower than VCC), A9 = VHH (14V), A0 = VIL (0.8V or below but higher than GND), and all other address pins equal VIL and data input pins equal VIH. Pulsing CE low starts the erase operation.
Erase Verify Mode
After an erase operation, all of the bytes in the chip must be verified to check whether they have been successfully erased to "1" or not. The erase verify mode automatically ensures a substantial erase margin. This mode will be entered after the erase operation if VPP = VPE (14V), CE = VIH, and OE = VIL.
Program Mode
Programming is performed exactly as it is in conventional UVEPROMs, and programming is the only way to change cell data from "1" to "0." The program mode is entered when VPP is raised to VPP (12V), VCC = VCP (5V), OE = VIH, the address pins equal the desired address, and the input pins equal the desired inputs. Pulsing CE low starts the programming operation.
Program Verify Mode
All of the bytes in the chip must be verified to check whether or not they have been successfully programmed with the desired data. Hence, after each byte is programmed, a program verify operation should be performed. The program verify mode automatically ensures a substantial program margin. This mode will be entered after the program operation if VPP = VPP (12V), CE = VIH, and OE = VIL.
Erase/Program Inhibit
Erase or program inhibit mode allows parallel erasing or programming of multiple chips with different data. When CE = VIH, erasing or programming of non-target chips is inhibited, so that except for the CE and OE pins, the W27E257 may have common inputs.
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W27E257
Standby Mode
The standby mode significantly reduces VCC current. This mode is entered when CE = VIH. In standby mode, all outputs are in a high impedance state, independent of OE.
Two-line Output Control
Since EPROMs are often used in large memory arrays, the W27E257 provides two control inputs for multiple memory connections. Two-line control provides for lowest possible memory power dissipation and ensures that data bus contention will not occur.
System Considerations
EPROM power switching characteristics require careful device decoupling. System designers are interested in three supply current issues: standby current levels (ISB), active current levels (ICC), and transient current peaks produced by the falling and rising edges of CE. Transient current magnitudes depend on the device output's capacitive and inductive loading. Two-line control and proper decoupling capacitor selection will suppress transient voltage peaks. Each device should have a 0.1 F ceramic capacitor connected between its VCC and GND. This high frequency, low inherentinductance capacitor should be placed as close as possible to the device. Additionally, for every eight devices, a 4.7 F electrolytic capacitor should be placed at the array's power supply connection between VCC and GND. The bulk capacitor will overcome voltage slumps caused by PC board trace inductances.
TABLE OF OPERATING MODES
(VPP = 12V, VPE = 14V, VHH = 12V, VCP = 5V, X = VIH or VIL)
MODE CE Read Output Disable Standby (TTL) Standby (CMOS) Program Program Verify Program Inhibit Erase Erase Verify Erase Inhibit Product Identifier-manufacturer Product Identifier-device VIL VIL VIH VCC 0.3V VIL VIH VIH VIL VIH VIH VIL VIL OE VIL VIH X X VIH VIL VIH VIH VIL VIH VIL VIL A0 X X X X X X X VIL X X VIL VIH
PINS A9 X X X X X X X VPE X X VHH VHH VCC VCC VCC VCC VCC VCP VCP VCP VCC VCC VCP VCC VCC VPP VCC VCC VCC VCC VPP VPP VPP VPE VPE VPP VCC VCC OUTPUTS DOUT High Z High Z High Z DIN DOUT High Z DIH DOUT High Z DA (Hex) 02 (Hex)
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Publication Release Date: January 1997 Revision A3
W27E257
DC CHARACTERISTICS
Absolute Maximum Ratings
PARAMETER Ambient Temperature with Power Applied Storage Temperature Voltage on all pins with Respect to Ground Except VPP, A9 and VCC pins Voltage on VPP Pin with Respect to Ground Voltage on A9 Pin with Respect to Ground Voltage on VCC Pin with Respect to Ground RATING -55 to +125 -65 to +125 -0.5 to VCC +0.5 -0.5 to +14.5 -0.5 to +14.5 -0.5 to +7 UNIT C C V V V V
Note: Exposure to conditions beyond those listed under Absolute Maximum Ratings may adversely affect the life and reliability of the device.
DC Erase Characteristics
(TA = 25 C 5 C, VCC = 5.0V 10%)
PARAMETER Input Load Current VCC Erase Current VPP Erase Current Input Low Voltage Input High Voltage Output Low Voltage (Verify) Output High Voltage (Verify) A9 Erase Voltage VPP Erase Voltage VCC Supply Voltage (Erase)
SYM. ILI ICP IPP VIL VIH VOL VOH VID VPE VCE
CONDITIONS MIN. VIN = VIL or VIH CE = VIL CE = VIL IOL = 2.1 mA IOH = -0.4 mA -10 -0.3 2.4 2.4 13.75 13.75 4.5
LIMITS TYP. 14 14 5.0 MAX. 10 30 30 0.8 5.5 0.45 14.25 14.25 5.5
UNIT A mA mA V V V V V V
Note: VCC must be applied simultaneously or before VPP and removed simultaneously or after VPP.
CAPACITANCE
(VCC = 5V, TA = 25 C, f = 1 MHz)
PARAMETER Input Capacitance Output Capacitance
SYMBOL CIN COUT
CONDITIONS VIN = 0V VOUT = 0V
MAX. 6 12
UNIT pF pF
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W27E257
AC CHARACTERISTICS
AC Test Conditions
PARAMETER Input Pulse Levels Input Rise and Fall Times Input and Output Timing Reference Level Output Load 0.45V to 2.4V 10 nS 0.8V/2.0V CL = 100 pF, IOH/IOL = -0.4 mA/2.1 mA CONDITIONS
AC Test Load and Waveform
+1.3V (IN914)
3.3K ohm
DOUT
100 pF (Including Jig and Scope)
Input
Test Points 2.4V 0.45V
2.0V 0.8V
Output
Test Points
2.0V 0.8V
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Publication Release Date: January 1997 Revision A3
W27E257
READ OPERATION DC CHARACTERISTICS
(VCC = 5.0V 10%, TA = 0 to 70 C) (W27E257-10, S-10, K-10, P-10: VCC, min. = 3.0V and max. = 5.5V)
PARAMETER Input Load Current Output Leakage Current VCC Standby Current
SYM. ILI ILO ISB ISB1
CONDITIONS MIN. VIN = 0V to VCC VOUT = 0V to VCC CE = VIH CE = VCC 0.2V CE = VIL IOUT = 0 mA f = 5 MHz VPP = VCC IOL = 2.1 mA IOH = -0.4 mA -5 -10 -
LIMITS TYP. 5 MAX. 5 10 1.0 100 30
UNIT A A mA A mA
VCC Operating Current
ICC
VPP Operating Current Input Low Voltage Input High Voltage Output Low Voltage Output High Voltage VPP Operating Voltage
IPP VIL VIH VOL VOH VPP
-0.3 2.0 2.4 VCC -0.7
-
100 0.8 VCC +0.5 0.45 VCC
A V V V V V
READ OPERATION AC CHARACTERISTICS
(VCC = 5.0V 10%, TA = 0 to 70 C)
PARAMETER Read Cycle Time Chip Enable Access Time Address Access Time Output Enable Access Time OE High to High-Z Output Output Hold from Address Change
SYM. TRC TCE TACC TOE TDF TOH
W27E257-10 MIN. 100 0 MAX. 100 100 50 30 -
W27E257-12 MIN. 120 0 MAX. 120 120 60 30 -
W27E257-15 MIN. 150 0 MAX. 150 150 70 50 -
UNIT nS nS nS nS nS nS
Note: VCC must be applied simultaneously or before VPP and removed simultaneously or after VPP.
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W27E257
DC PROGRAMMING CHARACTERISTICS
(VCC = 5.0V 10%, TA = 25 C 5 C)
PARAMETER Input Load Current VCC Program Current VPP Program Current Input Low Voltage Input High Voltage Output Low Voltage (Verify) Output High Voltage (Verify) A9 Silicon I.D. Voltage VPP Program Voltage VCC Supply Voltage (Program)
SYM. ILI ICP IPP VIL VIH VOL VOH VID VPP VCP
CONDITIONS MIN. VIN = VIL or VIH CE = VIL CE = VIL IOL = 2.1 mA IOH = -0.4 mA -10 -0.3 2.4 2.4 11.5 11.75 4.5
LIMITS TYP. 12.0 12.0 5.0 MAX. 10 30 30 0.8 5.5 0.45 12.5 12.25 5.5
UNIT A mA mA V V V V V V V
AC PROGRAMMING/ERASE CHARACTERISTICS
(VCC = 5.0V 10%, TA = 25 C 5 C)
PARAMETER VPP Setup Time Address Setup Time Data Setup Time CE Program Pulse Width CE Erase Pulse Width Data Hold Time OE Setup Time Data Valid from OE OE High to Output High Z Address Hold Time Address Hold Time after CE High (Erase)
SYM. MIN. TVPS TAS TDS TPWP TPWE TDH TOES TOEV TDFP TAH TAHC 2.0 2.0 2.0 95 95 2.0 2.0 0 0 2.0
LIMITS TYP. 100 100 MAX. 105 105 150 130 -
UNIT S S S S mS S S nS nS S S
Note: VCC must be applied simultaneously or before VPP and removed simultaneously or after VPP.
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Publication Release Date: January 1997 Revision A3
W27E257
TIMING WAVEFORMS
AC Read Waveform
VIH Address VIL VIH CE VIL Address Valid
TCE
VIH OE VIL TACC Outputs High Z TOE TOH Valid Output High Z TDF
Erase Waveform
Read Read Manufacturer Device SID SID A9 = 12.0V A0= VIH Others = VIL A0 = VIL Others = V IL TACC DA TACC 02 TDS 14.0V 5.0V VPP VIH CE VIL TOE VIH OE VIL TOEV TOE TPWE TOES TOE TCE 5V TVPS TAS TARC Data All One TAHC Chip Erase A9 = 14.0V Erase Verify Blank Check Read Verify
Address
VIH VIL
Others = VIL Address Stable TDFP DOUT TAH DOUT Address Stable Address Stable TACC DOUT
Data
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W27E257
Timing Waveforms, continued
Programming Waveform
Program VIH Address VIL TAS Data Address Stable
Program Verify Address Stable TDFP
Read Verify Address Valid
TACC DOUT DOUT
Data In Stable
DOUT
TDS 12.0V VPP 5.0V VIH CE VIL VIH OE VIL TPWP
TDH
TAH
5V TVPS
TOE TOES
TOEV
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Publication Release Date: January 1997 Revision A3
W27E257
SMART PROGRAMMING ALGORITHM
Start
Address = First Location
Vcc = 5V Vpp = 12V
X=0
Program One 100 Pulse S
Increment X Yes X = 25? No Fail Verify One Byte Pass Increment Address No Last Address? Yes Vcc = 5V Vpp = 5V Verify One Byte Pass Fail
Compare All Bytes to Original Data Pass Pass Device
Fail
Fail Device
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W27E257
SMART ERASE ALGORITHM
Start
X=0
Vcc = 5V Vpp = 14V
A9 = 14V; A0 = VIL Chip Erase 100 mS Pulse
Address = First Location
Increment X No Erase Verify Pass Yes Increment Address No Last Address? Yes Vcc = 5V Vpp = 5V Fail X = 20?
Compare All Bytes to FFs (HEX) Pass Pass Device
Fail
Fail Device
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Publication Release Date: January 1997 Revision A3
W27E257
ORDERING INFORMATION
PART NO. ACCESS TIME (nS) 100 120 150 100 120 150 POWER SUPPLY CURRENT MAX. (mA) 30 30 30 30 30 30 STANDBY VCC CURRENT MAX. (A) 100 100 100 100 100 100 PACKAGE
W27E257-10 W27E257-12 W27E257-15 W27E257P-10 W27E257P-12 W27E257P-15
Notes:
600 mil DIP 600 mil DIP 600 mil DIP 32-pin PLCC 32-pin PLCC 32-pin PLCC
1. Winbond reserves the right to make changes to its products without prior notice. 2. Purchasers are responsible for performing appropriate quality assurance testing on products intended for use in applications where personal injury might occur as a consequence of product failure.
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W27E257
PACKAGE DIMENSIONS
28-pin P-DIP
Dimension in Inches Dimension in mm
Symbol
Min. Nom. Max. Min.
0.210 0.010 0.150 0.016 0.058 0.008 0.155 0.018 0.060 0.010 1.460 0.590 0.540 0.090 0.120 0 0.630 0.650 0.600 0.545 0.100 0.130 0.160 0.022 0.064 0.014 1.470 0.610 0.550 0.110 0.140 15 0.670 0.090 14.99 13.72 2.29 3.05 0 16.00 0.25 3.81 0.41 1.47 0.20
Nom. Max.
5.33
D
28 15
A A1 A2 B B1 c D E E1 e1 L
a
3.94 0.46 1.52 0.25 37.08 15.24 13.84 2.54 3.30
4.06 0.56 1.63 0.36 37.34 15.49 13.97 2.79 3.56 15
E1
eA S Notes:
1 14
16.51
17.02 2.29
S
E
A A2
Base Plane
A1
c
L
Seating Plane
B B1 e1 a eA
1. Dimension D Max. & S include mold flash or tie bar burrs. 2. Dimension E1 does not include interlead flash. 3. Dimension D & E1 include mold mismatch and are determined at the mold parting line. 4. Dimension B1 does not include dambar protrusion/intrusion. 5. Controlling dimension: Inches. 6. General appearance spec. should be based on final visual inspection spec.
32-pin PLCC
HE E 4 1 32 30
Symbol
5 29
Dimension in Inches
Dimension in mm
Min. Nom.
0.020 0.105 0.026 0.016 0.008 0.547 0.447 0.044 0.490 0.390 0.585 0.485 0.075 0.110 0.028 0.018 0.010 0.550 0.450 0.050 0.51 0 0.410 0.590 0.49 0 0.090
Max.
0.140
Min. Nom.
0.50
Max.
3.56
D HD
GD
13
21
14
20
c
A A1 A2 b1 b c D E e GD GE HD HE L y Notes:
0.115 0.032 0.022 0.014 0.553 0.453 0.056 0.530 0.430 0.595 0.495 0.095 0.004
2.67 0.66 0.41 0.20 13.89 11.35 1.12 12.45 9.91 14.86 12.32 1.91
2.80 0.71 0.46 0.25 13.97 11.43 1.27 12.9 5 10.41 14.99 12.45 2.29
2.93 0.81 0.56 0.35 14.05 11.51 1.42 13.46 10.92 15.11 12.57 2.41 0.10
0
10
0
10
L A2 A
Seating Plane
e
b b1 GE
A1 y
1. Dimension D & E do not include interlead flash. 2. Dimension b does not include dambar protrusion/intrusion. 3. Controlling dimension: Inches. 4. General appearance spec. should be based on final visual inspection sepc.
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Publication Release Date: January 1997 Revision A3
W27E257
Headquarters
No. 4, Creation Rd. III, Science-Based Industrial Park, Hsinchu, Taiwan TEL: 886-3-5770066 FAX: 886-3-5792647 http://www.winbond.com.tw/ Voice & Fax-on-demand: 886-2-7197006
Winbond Electronics (H.K.) Ltd.
Rm. 803, World Trade Square, Tower II, 123 Hoi Bun Rd., Kwun Tong, Kowloon, Hong Kong TEL: 852-27513100 FAX: 852-27552064
Winbond Electronics North America Corp. Winbond Memory Lab. Winbond Microelectronics Corp. Winbond Systems Lab.
2730 Orchard Parkway, San Jose, CA 95134, U.S.A. TEL: 1-408-9436666 FAX: 1-408-9436668
Taipei Office
11F, No. 115, Sec. 3, Min-Sheng East Rd., Taipei, Taiwan TEL: 886-2-7190505 FAX: 886-2-7197502
Note: All data and specifications are subject to change without notice.
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