The MX27C2000A is a 5V only, 2M-bit, One Time
Programmable Read Only Memory. It is organized as
256K words by 8 bits per word, operates from a single +
5 volt supply, has a static standby mode, and features
fast single address location programming. All programming signals are TTL levels, requiring a single pulse. For
programming outside from the system, existing EPROM
PIN CONFIGURATIONS
32 PDIP/SOP
VPP
A16
A15
A12
GND
A7
A6
A5
A4
A3
A2
A1
A0
Q0
Q1
Q2
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
MX27C2000A
VCC
32
PGM
31
A17
30
A14
29
A13
28
A8
27
A9
26
A11
25
OE
24
A10
23
CE
22
Q7
21
Q6
20
Q5
19
Q4
18
Q3
17
• Operating current:30mA
• Standby current: 100uA
• Package type:
- 32 pin plastic DIP
- 32 pin PLCC
- 32 pin SOP
- 32 pin TSOP
programmers may be used. The MX27C2000A supports
a intelligent fast programming algorithm which can result
in programming time of less than one minute.
This One Time Programmable Read Only is packaged in
industry standard 32 pin dual-in-line packages, 32 lead
PLCC, 32 lead SOP, 32 lead TSOP packages.
32 PLCC
A12
A15
A16
VPP
VCC
PGM
A17
4
5
A7
A6
A5
A4
9
A3
A2
A1
A0
13
Q0
141720
Q1
1
32
MX27C2000A
Q2
Q3Q4Q5
GND
30
A14
29
A13
A8
A9
A11
25
OE
A10
CE
Q7
21
Q6
32 TSOP
A11
A13
A14
A17
PGM
VCC
VPP
A16
A15
A12
P/N: PM0708
1
2
A9
3
A8
4
5
6
7
8
9
10
11
12
13
A7
14
A6
15
A5
16
A4
MX27C2000A
PIN DESCRIPTION
32
OE
31
A10
30
CE
29
Q7
28
Q6
27
Q5
26
Q4
25
Q3
24
GND
23
Q2
22
Q1
21
Q0
20
A0
19
A1
18
A2
17
A3
SYMBOLPIN NAME
A0~A17Address Input
Q0~Q7Data Input/Output
CEChip Enable Input
OEOutput Enable Input
PGMProgrammable Enable Input
VPPProgram Supply Voltage
N CNo Internal Connection
VC CPower Supply Pin (+5V)
GN DGround Pin
1
REV. 1.8, JUL. 19, 2001
MX27C2000A
BLOCK DIAGRAM
CE
PGM
OE
A0~A17
ADDRESS
INPUTS
VCC
VSS
.
.
.
.
.
.
.
.
CONTROL
LOGIC
Y-DECODER
X-DECODER
VPP
OUTPUT
BUFFERS
.
Y-SELECT
.
.
.
2M BIT
.
.
.
.
CELL
MAXTRIX
Q0~Q7
FUNCTIONAL DESCRIPTION
THE PROGRAMMING OF THE MX27C2000A
When the MX27C2000A is delivered, or it is erased, the
chip has all 2M bits in the "ONE", or HIGH state.
"ZEROs" are loaded into the MX27C2000A through the
procedure of programming.
For programming, the data to be programmed is applied
with 8 bits in parallel to the data pins.
PROGRAM INHIBIT MODE
Programming of multiple MX27C2000As 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 MX27C2000A may be common. A
TTL low-level program pulse applied to an MX27C2000A
CE input with VPP = 12.5 ± 0.5 V and PGM LOW will
program that MX27C2000A. A high-level CE input
inhibits the other MX27C2000A 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°C ± 5°C ambient temperature range
that is required when programming the MX27C2000A.
VCC must be applied simultaneously or before VPP, and
removed simultaneously or after VPP. When
programming an MXIC OTP ROM, 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 = 6.25V and PGM = VIH (Algorithm is shown in
Figure 1). The programming is achieved by applying a
single TTL low level 10us 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
through each address of the device. When the
programming mode is completed, the data in all address
is verified at VCC = VPP = 5V ± 10%.
P/N: PM0708
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
MX27C2000A, 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.
READ MODE
The MX27C2000A 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)
2
REV. 1.8, JUL. 19, 2001
MX27C2000A
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 tOE after the falling edge
of OE, assuming that CE has been LOW and addresses
have been stable for at least tACC - tOE.
STANDBY MODE
The MX27C2000A 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
MX27C2000A 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 twoline 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
MODECEOEPGMA0A9VP POUTPUTS
ReadVI LVI LXXXVCCDOUT
Output DisableVILVIHXXXVC CHigh Z
Standby (TTL)VIHXXXXVC CHigh Z
Standby (CMOS)VCC±0.3VXXXXV C CHigh Z
ProgramVILVIHVILXXVPPDIN
Program VerifyVILVILVIHXXVPPDOUT
Program InhibitVIHXXXXVPPHigh Z
Manufacturer Code(3)VILVILXVILVHVCCC2H
Device Code(3)VILVILXVIHVHVCCC 3H
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: PM0708
3
REV. 1.8, JUL. 19, 2001
FIGURE 1. FAST PROGRAMMING FLOWCHART
MX27C2000A
ST ART
ADDRESS = FIRST LOCATION
VCC = 6.25V
VPP = 12.75V
X = 0
PROGRAM ONE 10us PULSE
INTERACTIVE
SECTION
VERIFY SECTION
INCREMENT ADDRESS
FAIL
NO
VCC = VPP = 5.25V
VERIFY ALL BYTES
INCREMENT X
X = 25?
NO
VERIFY BYTE
?
PASS
LAST ADDRESS
YES
?
PASS
DEVICE PASSED
YES
FAIL
FAIL
DEVICE FAILED
P/N: PM0708
4
REV. 1.8, JUL. 19, 2001
SWITCHING TEST CIRCUITS
MX27C2000A
DEVICE
UNDER
TEST
CL = 100 pF including jig capacitance
SWITCHING TEST WAVEFORMS
AC driving levels
AC TESTING: AC driving levels are 2.4V/0.4V for commercial grade.
1.8K ohm
CL
6.2K ohm
2.0V
TEST POINTS
0.8V
INPUT
Input pulse rise and fall times are equal to or less than 10ns.
DIODES = IN3064
OR EQUIVALENT
2.0V
0.8V
OUTPUT
+5V
P/N: PM0708
5
REV. 1.8, JUL. 19, 2001
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