IS93C56A Datasheet, PDF (2/16 Pages) Integrated Silicon Solution, Inc – 2K-BIT/4K-BIT SERIAL ELECTRICALLY ERASABLE PROM

IS93C56A
IS93C66A
PIN CONFIGURATIONS
8-Pin DIP, 8-Pin TSSOP
CS 1
SK 2
DIN 3
DOUT 4
8 VCC
7 NC
6 ORG
5 GND
8-Pin JEDEC SOIC “GR”
CS 1
SK 2
DIN 3
DOUT 4
8 VCC
7 NC
6 ORG
5 GND
ISSI ^®
PIN DESCRIPTIONS
CS
SK
DIN
DOUT
ORG
NC
Vcc
GND
Chip Select
Serial Data Clock
Serial Data Input
Serial Data Output
Organization Select
Not Connected
Power
Ground
Applications
The IS93C56A/66A are very popular in many
applications which require low-power, low-density
storage. Applications using these devices include
industrial controls, networking, and numerous other
consumer electronics.
Endurance and Data Retention
The IS93C56A/66A are designed for applications requiring
up to 1M programming cycles (WRITE, WRALL, ERASE
and ERAL). They provide 40 years of secure data retention
without power after the execution of 1M programming cycles.
Device Operations
The IS93C56A/66A are controlled by a set of
instructions which are clocked-in serially on the Din pin.
Before each low-to-high transition of the clock (SK), the
CS pin must have already been raised to HIGH, and the
Din value must be stable at either LOW or HIGH. Each
instruction begins with a start bit of the logical “1” or
HIGH. Following this are the opcode (2 bits),
address field (8 or 9 bits), and data, if appropriate. The
clock signal may be held stable at any moment to
suspend the device at its last state, allowing clock-
speed flexibility. Upon completion of bus
communication, CS would be pulled LOW. The device
then would enter Standby mode if no internal
programming is underway.
Read (READ)
The READ instruction is the only instruction that outputs
serial data on the DOUT pin. After the read instruction and
address have been decoded, data is transferred from the
selected memory register into a serial shift register. (Please
note that one logical “0” bit precedes the actual 8 or 16-bit
output data string.) The output on DOUT changes during the
low-to-high transitions of SK (see Figure 3).
Low Voltage Read
The IS93C56A/66A are designed to ensure that data read
operations are reliable in low voltage environments. They
provide accurate operation with Vcc as low as 1.8V.
Auto Increment Read Operations
In the interest of memory transfer operation applications,
the IS93C56A/66A are designed to output a continuous
stream of memory content in response to a single read
operation instruction. To utilize this function, the system
asserts a read instruction specifying a start location ad-
dress. Once the 8 or 16 bits of the addressed register have
been clocked out, the data in consecutively higher address
locations is output. The address will wrap around continu-
ously with CS HIGH until the chip select (CS) control pin is
brought LOW. This allows for single instruction data dumps
to be executed with a minimum of firmware overhead.
2
Integrated Silicon Solution, Inc. — www.issi.com — 1-800-379-4774
Rev. A
05/02/06