93AA76C-I/ST Microchip Technology, 93AA76C-I/ST Datasheet - Page 5

• Manufacturer Part Number: 93AA76C-I/ST
• Description: IC EEPROM 8KBIT 3MHZ 8TSSOP
• Manufacturer: Microchip Technology

Specifications of 93AA76C-I/ST

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 8K (1K x 8 or 512 x 16)
• Speed: 3MHz
• Interface: Microwire, 3-Wire Serial
• Voltage - Supply: 1.8 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-TSSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2.0
When the ORG pin (93XX76C) is connected to V
the (x16) organization is selected. When it is connected
to ground, the (x8) organization is selected. Instruc-
tions, addresses and write data are clocked into the DI
pin on the rising edge of the clock (CLK). The DO pin is
normally held in a High-Z state except when reading
data from the device, or when checking the Ready/
Busy
Ready/
Write operation by polling the DO pin; DO low indicates
that programming is still in progress, while DO high
indicates the device is ready. DO will enter the High-Z
state on the falling edge of CS.
2.1
The Start bit is detected by the device if CS and DI are
both high with respect to the positive edge of CLK for
the first time.
Before a Start condition is detected, CS, CLK and DI
may change in any combination (except to that of a
Start condition), without resulting in any device
operation (Read, Write, Erase, EWEN, EWDS, ERAL
or WRAL). As soon as CS is high, the device is no
longer in Standby mode.
An instruction following a Start condition will only be
executed if the required opcode, address and data bits
for any particular instruction are clocked in.
2.2
It is possible to connect the Data In and Data Out pins
together. However, with this configuration it is possible
for a “bus conflict” to occur during the “dummy zero”
that precedes the read operation if A0 is a logic high-
level. Under such a condition the voltage level seen at
Data Out is undefined and will depend upon the relative
impedances of Data Out and the signal source driving
A0. The higher the current sourcing capability of the
driver, the higher the voltage at the Data Out pin. In
order to limit this current, a resistor should be
connected between DI and DO.
© 2008 Microchip Technology Inc.
Note:
status during a programming operation. The
Busy
FUNCTIONAL DESCRIPTION
Start Condition
Data In/Data Out (DI/DO)
93AA76A/B/C, 93LC76A/B/C, 93C76A/B/C
When preparing to transmit an instruction,
either the CLK or DI signal levels must be
at a logic low as CS is toggled active high.
status can be verified during an Erase/
CC
,
2.3
All modes of operation are inhibited when V
a typical voltage of 1.5V for ‘93AA’ and ‘93LC’ devices
or 3.8V for ‘93C’ devices.
The EWEN and EWDS commands give additional
protection against accidentally programming during
normal operation.
After power-up the device is automatically in the EWDS
mode. Therefore, an EWEN instruction must be
performed before the initial ERASE or WRITE instruction
can be executed.
Block Diagram
ORG*
DI
CLK
Note:
Note:
CS
PE*
*ORG and PE inputs are not available on
A/B devices.
Data Protection
Data Register
V
For added protection, an EWDS command
should be performed after every write
operation and an external 10 kΩ pull-down
protection resistor should be added to the
CS pin.
To prevent accidental writes to the array in
the 93XX76C devices, set the PE pin to a
logic low.
CC
Memory
Register
Array
Decode
Clock
Mode
Logic
V
SS
Address
Decoder
Address
Counter
DS21796K-page 5
Output
Buffer
CC
is below
DO