MX27L2000
2M-BIT [256Kx8] CMOS EPROM
FEATURES
•
•
•
•
•
•
•
256Kx 8 organization
Wide power supply range, 2.7V DC to 3.6V DC
+12.5V programming voltage
Fast access time: 120/150/200/250 ns
Totally static operation
Completely TTL compatible
Operating current:20mA @ 3.6V, 5MHz
•
Standby current: 20uA
•
Package type:
-
-
-
-
-
32 pin ceramic DIP, plastic DIP
32 pin SOP
8x20mm 32-lead TSOP(I)
8x14mm 32-lead TSOP(I)
8x13.4mm 32-lead TSOP(I)
GENERAL DESCRIPTION
The MX27L2000 is a 3V only, 2M-bit, ultraviolet Erasable
Programmable Read Only Memory. It is organized as
256K words by 8 bits per word, operates from a single +
3 volt supply, has a static standby mode, and features
fast single address location programming. All program-
ming signals are TTL levels, requiring a single pulse. For
programming outside from the system, existing EPROM
programmers may be used. The MX27L2000 supports a
intelligent fast programming algorithm which can result in
programming time of less than one minute.
This EPROM is packaged in industry standard 32 pin
dual-in-line packages, 32 lead SOP and 32 lead TSOP(I)
packages.
PIN CONFIGURATIONS
32 CDIP/PDIP/SOP
VPP
A16
A15
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
15
16
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
VCC
PGM
A17
A14
A13
A8
A9
A11
OE
A10
CE
Q7
Q6
Q5
Q4
Q3
BLOCK DIAGRAM
CE
PGM
OE
CONTROL
LOGIC
OUTPUT
BUFFERS
Q0~Q7
MX27L2000
.
.
A0~A17
ADDRESS
INPUTS
.
.
.
.
.
.
VCC
VSS
Y-DECODER
.
.
.
.
Y-SELECT
X-DECODER
.
.
.
.
2M BIT
CELL
MAXTRIX
32 TSOP(I) (8x20mm,8x14mm,8x13.4mm)
A11
A9
A8
A13
A14
A17
PGM
VCC
VPP
A16
A15
A12
A7
A6
A5
A4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
OE
A10
CE
Q7
Q6
Q5
Q4
Q3
GND
Q2
Q1
Q0
A0
A1
A2
A3
PIN DESCRIPTION
SYMBOL
A0~A17
Q0~Q7
CE
OE
PGM
VPP
NC
VCC
GND
PIN NAME
Address Input
Data Input/Output
Chip Enable Input
Output Enable Input
Programmable Enable Input
Program Supply Voltage
No Internal Connection
Power Supply Pin (+5V)
Ground Pin
REV.2.5, APR 09,1998
MX27L2000
P/N: PM0372
1
MX27L2000
FUNCTIONAL DESCRIPTION
THE ERASURE OF THE MX27L2000
The MX27L2000 is erased by exposing the chip to an
ultraviolet light source. A dosage of 15 W seconds/cm
2
is
required to completely erase a MX27L2000. This dosage
can be obtained by exposure to an ultraviolet lamp -
wavelength of 2537 Angstroms (A) - with intensity of
12,000 uW/cm
2
for 15 to 20 minutes. The MX27L2000
should be directly under and about one inch from the
source and all filters should be removed from the UV light
source prior to erasure.
It is important to note that the MX27L2000, and similar
devices, will be cleared for all bits of their programmed
states with light sources having wavelengths shorter than
4000 A. Although erasure times will be much longer than
that with UV sources at 2537 A, nevertheless the
exposure to fluorescent light and sunlight will eventually
erase the MX27L2000 and exposure to them should be
prevented to realize maximum system reliability. If used
in such an environment, the package window should be
covered by an opaque label or substance.
through each address of the device. When the
programming mode is completed, the data in all address
is verified at VCC = VPP = 5V
±
10%.
PROGRAM INHIBIT MODE
Programming of multiple MX27L2000s in parallel with
different data is also easily accomplished by using the
Program Inhibit Mode. Except for CE and OE, all like
inputs of the parallel MX27L2000 may be common. A TTL
low-level program pulse applied to an MX27L2000 CE
input with VPP = 12.5
±
0.5 V and PGM LOW will program
that MX27L2000. A high-level CE input inhibits the other
MX27L2000s from being programmed.
PROGRAM VERIFY MODE
Verification should be performed on the programmed bits
to determine that they were correctly programmed. The
verification should be performed with OE and CE, at VIL,
PGM at VIH, and VPP at its programming voltage.
AUTO IDENTIFY MODE
The auto identify mode allows the reading out of a binary
code from an EPROM that will identify its manufacturer
and device type. This mode is intended for use by
programming equipment for the purpose of automatically
matching the device to be programmed with its
corresponding programming algorithm. This mode is
functional in the 25°
±
5°C ambient temperature range
C
that is required when programming the MX27L2000.
To activate this mode, the programming equipment must
force 12.0
±
0.5 V on address line A9 of the device. Two
identifier bytes may then be sequenced from the device
outputs by toggling address line A0 from VIL to VIH. All
other address lines must be held at VIL during auto
identify mode.
Byte 0 ( A0 = VIL) represents the manufacturer code, and
byte 1 (A0 = VIH), the device identifier code. For the
MX27L2000, these two identifier bytes are given in the
Mode Select Table. All identifiers for manufacturer and
device codes will possess odd parity, with the MSB (Q7)
defined as the parity bit.
THE PROGRAMMING OF THE MX27L2000
When the MX27L2000 is delivered, or it is erased, the
chip has all 2M bits in the "ONE" or HIGH state. "ZEROs"
are loaded into the MX27L2000 through the procedure of
programming.
For programming, the data to be programmed is applied
with 8 bits in parallel to the data pins.
Vcc must be applied simultaneously or before Vpp, and
removed simultaneously or after Vpp. When
programming an MXIC EPROM, a 0.1uF capacitor is
required across Vpp and ground to suppress spurious
voltage transients which may damage the device.
FAST PROGRAMMING
The device is set up in the fast programming mode when
the programming voltage VPP = 12.75V is applied, with
VCC = 6.25 V and PGM = VIH (Algorithm is shown in
Figure 1). The programming is achieved by applying a
single TTL low level 100us pulse to the PGM input after
addresses and data line are stable. If the data is not
verified, an additional pulse is applied for a maximum of
25 pulses. This process is repeated while sequencing
P/N: PM0372
REV.2.5, APR 09,1998
2
MX27L2000
READ MODE
The MX27L2000 has two control functions, both of which
must be logically satisfied in order to obtain data at the
outputs. Chip Enable (CE) is the power control and
should be used for device selection. Output Enable (OE)
is the output control and should be used to gate data to the
output pins, independent of device selection. Assuming
that addresses are stable, address access time (tACC) is
equal to the delay from CE to output (tCE). Data is
available at the outputs tQE after the falling edge of OE,
assuming that CE has been LOW and addresses have
been stable for at least tACC - tQE.
STANDBY MODE
The MX27L2000 has a CMOS standby mode which
reduces the maximum VCC current to 100 uA. It is placed
in CMOS standby when CE is at VCC
±
0.3 V. The
MX27L2000 also has a TTL-standby mode which reduces
the maximum VCC current to 1.5 mA. It is placed in TTL-
standby when CE is at VIH. When in standby mode, the
outputs are in a high-impedance state, independent of the
OE input.
TWO-LINE OUTPUT CONTROL FUNCTION
To accommodate multiple memory connections, a two-
line control function is provided to allow for:
1. Low memory power dissipation,
2. Assurance that output bus contention will not occur.
It is recommended that CE be decoded and used as the
primary device-selecting function, while OE be made a
common connection to all devices in the array and
connected to the READ line from the system control bus.
This assures that all deselected memory devices are in
their low-power standby mode and that the output pins
are only active when data is desired from a particular
memory device.
SYSTEM CONSIDERATIONS
During the switch between active and standby conditions,
transient current peaks are produced on the rising and
falling edges of Chip Enable. The magnitude of these
transient current peaks is dependent on the output
capacitance loading of the device. At a minimum, a 0.1 uF
ceramic capacitor (high frequency, low inherent
inductance) should be used on each device between Vcc
and GND to minimize transient effects. In addition, to
overcome the voltage drop caused by the inductive
effects of the printed circuit board traces on EPROM
arrays, a 4.7 uF bulk electrolytic capacitor should be used
between VCC and GND for each eight devices. The
location of the capacitor should be close to where the
power supply is connected to the array.
MODE SELECT TABLE
PINS
MODE
Read
Output Disable
Standby (TTL)
Standby (CMOS)
Program
Program Verify
Program Inhibit
Manufacturer Code(3)
Device Code(3)
CE
VIL
VIL
VIH
VCC±0.3V
VIL
VIL
VIH
VIL
VIL
OE
VIL
VIH
X
X
VIH
VIL
X
VIL
VIL
PGM
X
X
X
X
VIL
VIH
X
X
X
A0
X
X
X
X
X
X
X
VIL
VIH
A9
X
X
X
X
X
X
X
VH
VH
VPP
VCC
VCC
VCC
VCC
VPP
VPP
VPP
VCC
VCC
OUTPUTS
DOUT
High Z
High Z
High Z
DIN
DOUT
High Z
C2H
20H
NOTES:
1. VH = 12.0 V
±
0.5 V
2. X = Either VIH or VIL
3. A1 - A8 = A10 - A17 = VIL(For auto select)
4. See DC Programming Characteristics for VPP voltage during
programming.
P/N: PM0372
REV.2.5, APR 09,1998
3
MX27L2000
FIGURE 1. FAST PROGRAMMING FLOW CHART
START
ADDRESS = FIRST LOCATION
VCC = 6.25V
VPP = 12.75V
X=0
PROGRAM ONE 100us PULSE
INTERACTIVE
SECTION
INCREMENT X
YES
X = 25?
NO
FAIL
VERIFY BYTE
?
PASS
NO
INCREMENT ADDRESS
LAST ADDRESS
FAIL
YES
VCC = VPP = 5.25V
VERIFY SECTION
VERIFY ALL BYTES
?
FAIL
DEVICE FAILED
PASS
DEVICE PASSED
P/N: PM0372
REV.2.5, APR 09,1998
4
MX27L2000
SWITCHING TEST CIRCUITS
DEVICE
UNDER
TEST
1.8K ohm
+5V
CL
6.2K ohm
DIODES = IN3064
OR EQUIVALENT
CL = 100 pF including jig capacitance (30pF for MX27L2000-120, 150ns)
SWITCHING TEST WAVEFORMS
2.0V
AC driving levels
2.0V
TEST POINTS
0.8V
OUTPUT
0.8V
INPUT
AC TESTING: AC driving levels are 3.0V/0V for both commercial grade and industrial grade.
Input pulse rise and fall times are < 10ns.
AC driving levels
1.5V
TEST POINTS
OUTPUT
1.5V
INPUT
AC TESTING: (1) AC driving levels are 3.0V/0V for commercial grade and industrial grade.
Input pulse rise and fall times are < 10ns.
(2) For MX27L2000-12/15.
P/N: PM0372
REV.2.5, APR 09,1998
5
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