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www.fairchildsemi.com
NM93C66A Rev. E.1
N
(
T
February 2000
2000 Fairchild Semiconductor International
NM93C66A
4K-Bit Serial CMOS EEPROM
(MICROWIRE Synchronous Bus)
General Description
NM93C66A is a 4096-bit CMOS non-volatile EEPROM organized
as 256 x 16-bit array. This device features MICROWIRE interface
which is a 4-wire serial bus with chipselect (CS), clock (SK), data
input (DI) and data output (DO) signals. This interface is compat-
ible to many of standard Microcontrollers and Microprocessors.
This device offers a pin (ORG), using which, the user can select
the format of the data (16-bit or 8-bit). If ORG is tied to GND, then
8-bit format is selected, while if ORG is tied to V
CC
, then 16-bit
format is selected. There are 7 instructions implemented on the
NM93C66A for various Read, Write, Erase, and Write Enable/
Disable operations. This device is fabricated using Fairchild
Semiconductor floating-gate CMOS process for high reliability,
high endurance and low power consumption.
“LZ” and “L” versions of NM93C66A offer very low standby current
making them suitable for low power applications. This device is
offered in both SO and TSSOP packages for small space consid-
erations.
Functional Diagram
Features
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Wide V
CC
2.7V - 5.5V
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User selectable organization
x16 (ORG = 1)
x8 (ORG = 0)
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Typical active current of 200
μ
A
10
μ
A standby current typical
1
μ
A standby current typical (L)
0.1
μ
A standby current typical (LZ)
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No Erase instruction required before Write instruction
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Self timed write cycle
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Device status during programming cycles
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40 year data retention
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Endurance: 1,000,000 data changes
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Packages available: 8-pin SO, 8-pin DIP, 8-pin TSSOP
INSTRUCTION
DECODER
CONTROL LOGIC
AND CLOCK
GENERATORS
HIGH VOLTAGE
GENERATOR
AND
PROGRAM
TIMER
INSTRUCTION
REGISTER
ADDRESS
REGISTER
EEPROM ARRAY
READ/WRITE AMPS
DATA IN/OUT REGISTER
16/8 BITS
DECODER
16
16
DATA OUT BUFFER
CS
SK
DI
ORG
DO
V
SS
V
CC