The MX27C8000A is a 5V only, 8M-bit, ultraviolet Erasable Programmable Read Only Memory. It is organized
as 1M 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
A19
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
MX27C8000A
VCC
32
A18
31
A17
30
A14
29
A13
28
A8
27
A9
26
A11
25
OE/VPP
24
A10
23
CE
22
Q7
21
Q6
20
Q5
19
Q4
18
Q3
17
• Operating current: 60mA
• Standby current: 100uA
• Package type:
- 32 pin plastic DIP
- 32 pin PLCC
- 32 pin SOP
- 32 pin TSOP
programmers may be used. The MX27C8000A supports
a intelligent fast programming algorithm which can result
in programming time of less than two minutes.
This EPROM is packaged in industry standard 32 pin
dual-in-line packages, 32 lead PLCC, 32 lead SOP and 32
lead TSOP packages.
When the MX27C8000A is delivered, or it is erased, the
chip has all 8M bits in the "ONE" or HIGH state. "ZEROs"
are loaded into the MX27C8000A 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
PROGRAM INHIBIT MODE
Programming of multiple MX27C8000As 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 MX27C8000A may be common. A
TTL low-level program pulse applied to an MX27C8000A
CE input with OE/VPP = 12.5 ± 0.5 Vwill program that
MX27C8000A. A high-level CE input inhibits the other
MX27C8000As 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 /VPPand CE,
at VIL, data should be verified tDV after the falling edge
of CE.
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 MX27C8000A.
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.
The device is set up in the fast programming mode when
the programming voltage OE/VPP = 12.75V is applied,
with VCC = 6.25 V (Algorithm is shown in Figure 1). The
programming is achieved by applying a single TTL low
level 50us pulse to the CE 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 = 5V
± 10%.
P/N: PM00764
Byte 0 ( A0 = VIL) represents the manufacturer code, and
byte 1 (A0 = VIH), the device identifier code. For the
MX27C8000A, 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 MX27C8000A 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
2
REV.1.2, JUL. 19, 2001
MX27C8000A
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 tOE after the falling edge
of OE's, assuming that CE has been LOW and
addresses have been stable for at least tACC - tOE.
STANDBY MODE
The MX27C8000A 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
MX27C8000A 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
MODECEOE/VPPA0A9OUTPUTS
ReadVI LVILXXDOUT
Output DisableVILVIHXXHigh Z
Standby (TTL)VIHXXXHigh Z
Standby (CMOS)VCC ±0.3VXXXHigh Z
ProgramVILVPPXXDIN
Program VerifyVILVILXXDOUT
Program InhibitVIHVPPXXHigh Z
Manufacturer Code(3)VILVILVILVHC2 H
Device Code(3)VILVILVIHVH02 H
NOTES:
1. VH = 12.0 V ± 0.5 V
2. X = Either VIH or VIL
3. A1 - A8 = A10 - A19 = VIL (For auto select)
4. See DC Programming Characteristics for VPP voltage during programming
P/N: PM00764
3
REV.1.2, JUL. 19, 2001
FIigure 1. FAST PROGRAMMING FLOW CHART
ADDRESS = FIRST LOCATION
VCC = 6.25V
OE/VPP = 12.75V
PROGRAM ONE 50 us PULSE
MX27C8000A
START
INCREMENT ADDRESS
INCREMENT ADDRESS
NO
LAST
ADDRESS ?
YES
PASS
NO
ADDRESS = FIRST LOCATION
PROGRAM ONE 50us PULSE
LAST
ADDRESS ?
X = 0
VERIFY BYTE
VCC = 5.25V
OE/VPP = VIL
COMPARE
ALL BYTES
TO ORIGINAL
DATA
DEVICE PASSED
YES
PASS
FAIL
NO
FAIL
INCREMENT X
X = 25 ?
YES
DEVICE FAILED
P/N: PM00764
4
REV.1.2, JUL. 19, 2001
SWITCHING TEST CIRCUITS
MX27C8000A
DEVICE
UNDER
TEST
SWITCHING TEST WAVEFORMS
AC driving levels
AC TESTING: AC driving levels are 2.4V/0.4V for commercial grade.
CL
6.2K ohm
CL = 100 pF including jig capacitance
2.0V
TEST POINTS
0.8V
INPUT
Input pulse rise and fall times are < 10ns.
1.8K ohm
+5V
DIODES = IN3064
OR EQUIVALENT
2.0V
0.8V
OUTPUT
P/N: PM00764
5
REV.1.2, JUL. 19, 2001
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