28LV64A
64K (8K x 8) Low Voltage CMOS EEPROM
FEATURES
PACKAGE TYPES
• 2.7V to 3.6V Supply
RDY/BSY
A12
A7
• 1
2
28 Vcc
27 WE
26 NC
25 A8
• Read Access Time—300 ns
• CMOS Technology for Low Power Dissipation
- 8 mA Active
- 50 µA CMOS Standby Current
• Byte Write Time—3 ms
• Data Retention >200 years
• High Endurance - Minimum 100,000 Erase/Write
Cycles
• Automatic Write Operation
- Internal Control Timer
3
A6
4
A6
A5
A4
A3
A2
A1 10
A0 11
NC 12
I/O0 13
5
6
7
8
9
29 A8
28 A9
A5
5
24 A9
A4
6
23 A11
22 OE
21 A10
20 CE
19 I/O7
18 I/O6
17 I/O5
16 I/O4
15 I/O3
27 A11
26 NC
25 OE
24 A10
23 CE
22 I/O7
21 I/O6
A3
7
A2
8
A1
9
A0
10
11
12
13
I/O0
I/O1
I/O2
VSS 14
-
Auto-Clear Before Write Operation
• Pin 1 indicator on PLCC on top of package
- On-Chip Address and Data Latches
• Data Polling
• Ready/Busy
• Chip Clear Operation
• Enhanced Data Protection
- VCC Detector
OE
A11
A9
1
2
3
4
5
6
7
28 A10
27 CE
26 I/07
25 I/06
24 I/05
23 I/04
22 I/03
A8
NC
WE
Vcc
RDY/BSY
A12
8
9
21 Vss
20 I/02
19 I/01
18 I/00
17 A0
16 A1
15 A2
- Pulse Filter
- Write Inhibit
A7 10
A6 11
A5 12
A4 13
A3 14
• Electronic Signature for Device Identification
• Organized 8Kx8 JEDEC Standard Pinout
- 28-pin Dual-In-Line Package
- 32-pin Chip Carrier (Leadless or Plastic)
- 28-pin Thin Small Outline Package (TSOP)
8x20mm
OE
A11
A9
22
23
24
25
26
27
A10
CE
21
20
19
18
17
16
15
14
13
12
11
10
9
I/O7
I/O6
I/O5
I/O4
I/O3
VSS
I/O2
I/O1
I/O0
A0
A8
NC
WE
VCC
28
1
RDY/BSY
-
28-pin Very Small Outline Package (VSOP)
8x13.4mm
2
3
4
5
6
7
A12
A7
A6
A5
A4
A3
• Available for Extended Temperature Ranges:
- Commercial: 0˚C to +70˚C
A1
A2
8
- Industrial: -40˚C to +85˚C
BLOCK DIAGRAM
DESCRIPTION
I/O0...................I/O7
The Microchip Technology Inc. 28LV64A is a CMOS 64K non-vol-
atile electrically Erasable PROM organized as 8K words by 8 bits.
The 28LV64A is accessed like a static RAM for the read or write
cycles without the need of external components. During a “byte
write”, the address and data are latched internally, freeing the
microprocessor address and data bus for other operations. Fol-
lowing the initiation of write cycle, the device will go to a busy state
and automatically clear and write the latched data using an inter-
nal control timer. To determine when the write cycle is complete,
the user has a choice of monitoring the Ready/Busy output or
using Data polling. The Ready/Busy pin is an open drain output,
which allows easy configuration in ‘wired-or’ systems. Alterna-
tively, Data polling allows the user to read the location last written
to when the write operation is complete. CMOS design and pro-
cessing enables this part to be used in systems where reduced
power consumption and reliability are required. A complete family
of packages is offered to provide the utmost flexibility in applica-
tions.
VSS
Data Protection
VCC
Circuitry
Chip Enable/
Output Enable
Control Logic
CE
OE
Auto Erase/Write
Timing
Data
Poll
WE
Input/Output
Buffers
Rdy/
Busy
Program Voltage
Generation
A0
Y
I
I
I
I
I
I
I
I
Y Gating
Decoder
L
a
t
c
h
e
s
64K bit
Cell Matrix
X
Decoder
I
I
I
A12
1996 Microchip Technology Inc.
Preliminary
DS21113B-page 1
This document was created with FrameMaker 4 0 4