A93C46
AiT Semiconductor Inc.
www.ait-ic.com
THREE-WIRE SERIAL EEPROM
1K (128 X 8 OR 64 X 16)
DETAILED INFORMATION
The A93C46 is accessed via a simple and versatile three-wire serial communication interface. Device
operation is controlled by seven instructions issued by the host processor. A valid instruction starts with a
rising edge of CS and consists of a start bit (logic“1”) followed by the appropriate op code and the desired
memory address location.
Instruction set for the A93C46
Address
Data
Instruction
SB
OP Code
Comments
x8
A6 - A0
x16
x8
x16
Reads data stored in memory,
at specified address
Write enable must precede all
programming modes
READ
EWEN
1
1
10
00
A5 - A0
11XXXXX 11XXXX
Erase memory location An - A0
Writes memory location An - A0
ERASE
WRITE
1
1
11
01
A6 - A0
A6 - A0
A5 - A0
A5 - A0
D7 - D0 D15 - D0
Erases all memory locations.
Valid only at VCC = 4.5V to 5.5V
Writes all memory locations.
Valid only at VCC = 4.5V to 5.5V
Disables all programming
instructions
ERAL
WRAL
EWDS
1
1
1
00
00
00
10XXXXX 10XXXX
01XXXXX 01XXXX D7 - D0 D15 - D0
00XXXXX 00XXXX
Note: The X’s in the address field represent don’t care values and must be clocked.
READ (READ): The Read (READ) instruction contains the address code for the memory location to be read.
After the instruction and address are decoded, data from the selected memory location is available at the
serial output pin DO. Output data changes are synchronized with the rising edges of serial clock SK. It should
be noted that a dummy bit (logic “0”) precedes the 8- bit or 16-bit data output string.
ERASE/WRITE (EWEN): To assure data integrity, the part automatically goes into the Erase/Write Disable
(EWDS) state when power is first applied. An Erase/Write Enable (EWEN) instruction must be executed first
before any programming instructions can be carried out. Please note that once in the EWEN state,
programming remains enabled until an EWDS instruction is executed or VCC power is removed from the part.
REV1.2
- FEB 2010 RELEASED, FEB 2012 DATED -
- 7 -
AITSEMI [ AiT Semiconductor ]
