X5043 Datasheet, PDF (2/20 Pages) Xicor Inc. – CPU Supervisor with 4K SPI EEPROM

X5043/X5045
The memory portion of the device is a CMOS Serial
EEPROM array with Xicor’s block lock protection. The
array is internally organized as x 8. The device features
a Serial Peripheral Interface (SPI) and software proto-
col allowing operation on a simple four-wire bus.
The device utilizes Xicor’s proprietary Direct Write^™
cell, providing a minimum endurance of 1,000,000
cycles and a minimum data retention of 100 years.
PIN CONFIGURATION
8-Lead SOIC/PDIP/MSOP
CS/WDI
SO
WP
V_SS
1
8
2
7
3 ^X5043/45 6
4
5
V_CC
RESET/RESET
SCK
SI
CS
SO
NC
NC
NC
WP
V_SS
14-Lead TSSOP
1
14
2
13
3
12
4 ^X5043/45 11
5
10
6
9
7
8
V_CC
RESET/RESET
NC
NC
NC
SCK
SI
PIN DESCRIPTIONS
Serial Output (SO)
SO is a push/pull serial data output pin. During a read
cycle, data is shifted out on this pin. Data is clocked out
by the falling edge of the serial clock.
Serial Input (SI)
SI is the serial data input pin. All opcodes, byte
addresses, and data to be written to the memory are
input on this pin. Data is latched by the rising edge of
the serial clock.
Serial Clock (SCK)
The Serial Clock controls the serial bus timing for data
input and output. Opcodes, addresses, or data present
on the SI pin is latched on the rising edge of the clock
input, while data on the SO pin changes after the fall-
ing edge of the clock input.
Chip Select (CS)
When CS is high, the X5043/45 is deselected and the
SO output pin is at high impedance and, unless an
internal write operation is underway, the X5043/45 will
be in the standby power mode. CS low enables the
X5043/45, placing it in the active power mode. It should
be noted that after power-up, a high to low transition on
CS is required prior to the start of any operation.
Write Protect (WP)
When WP is low, nonvolatile writes to the X5043/45 are
disabled, but the part otherwise functions normally.
When WP is held high, all functions, including non vol-
atile writes operate normally. WP going low while CS is
still low will interrupt a write to the X5043/45. If the
internal write cycle has already been initiated, WP
going low will have no affect on a write.
Reset (RESET, RESET)
X5043/45, RESET/RESET is an active low/HIGH,
open drain output which goes active whenever V_CC
falls below the minimum V_CC sense level. It will remain
active until V_CC rises above the minimum V_CC sense
level for 200ms. RESET/RESET also goes active if the
Watchdog timer is enabled and CS remains either high
or low longer than the Watchdog time out period. A fall-
ing edge of CS will reset the watchdog timer.
PIN NAMES
Symbol
CS
SO
SI
SCK
WP
V_SS
V_CC
RESET/RESET
Description
Chip Select Input
Serial Output
Serial Input
Serial Clock Input
Write Protect Input
Ground
Supply Voltage
Reset Output
REV 1.1.2 5/29/01
www.xicor.com
Characteristics subject to change without notice. 2 of 20