2
S93VP662/S93VP663
2019 1.1 5/15/98
PIN FUNCTIONS
Pin Name Function
CS Chip Select
SK Clock Input
DI Serial Data Input
DO Serial Data Output
V
CC
+2.7 to 6.0V Power Supply
GND Ground
PIN CONFIGURATION
DIP Package (P)
SOIC Package (S)
DEVICE OPERATION
APPLICATIONS
The S93VP662/VP663 was designed specifically for
applications where the integrity of the stored data is
paramount. In recent years, as the operating voltage
range of serial E2PROMs has widened, most semiconductor manufacturers have arbitrarily eliminated their
V
CC
sense circuits. The S93VP662/VP663 will protect
your data by guaranteeing write lockout below the selected VCC Lockout voltage.
VCC Lockout
The S93VP662/VP663 has an on-board precision V
CC
sense circuit. Whenever VCC is below V
LOCK
, the
S93VP662/VP663 will disable the internal write circuitry.
The VCC lockout circuit will ensure a higher level of data
integrity than can be expected from industry standard
devices that have either a very loose specification or no
VCC lockout specification.
During a power-on sequence all writes will be inhibited
below the V
LOCK
level and will continue to be held in a
write inhibit state for approximately 200ms after V
CC
reaches, then stays at or above V
LOCK
. The 200ms delay
provides a buffer space for the microcontroller to complete its power-on initialization routines (reading is OK)
while still protecting against inadvertent writes.
During a power-down sequence initiation of writes will
be inhibited whenever VCC falls below V
LOCK
. This will
guard against the system’s microcontroller performing
an inadvertent write within the ‘danger zone’. (see
AN003)
GENERAL OPERATION
The S93VP662/VP663 is a 4096-bit nonvolatile memory
intended for use with industry standard microprocessors. The S93VP663 is organized as X16, seven 11-bit
instructions control the reading, writing and erase
operations of the device. The S93VP662 is organized as
X8, seven 12-bit instructions control the reading, writing
and erase operations of the device. The device operates
on a single 3V or 5V supply and will generate on chip, the
high voltage required during any write operation.
Instructions, addresses, and write data are clocked into
the DI pin on the rising edge of the clock (SK). The DO
pin is normally in a high impedance state except when
reading data from the device, or when checking the
ready/busy status after a write operation.
The ready/busy status can be determined after the start
of a write operation by selecting the device (CS high) and
polling the DO pin; DO low indicates that the write
operation is not completed, while DO high indicates that
the device is ready for the next instruction. If necessary,
the DO pin may be placed back into a high impedance
2019 ILL1 1.0
CS
SK
DI
DO
V
CC
NC
NC
GND
1
2
3
4
8
7
6
5
CS
SK
DI
DO
V
CC
NC
NC
GND
1
2
3
4
8
7
6
5