SMS8198
PIN CONFIGURATIONS
TRI_RESET# - is an active low open drain output. It is
driven low whenever VCC is below VTRIP. TRI_RESET# is
also an input and can be used to debounce a switch input
or perform signal conditioning. The TRI_RESET# pin
does have an internal pull-up and should be left uncon-
nected if the signal is not used in the system. However,
when the pin is tied to a system TRI_RESET# line an
external pull-up resistor should be employed.
8-Pin SOIC
1
2
3
4
8
7
6
5
V
CC
WP
SCL
SDA
NC
TRI_RESET#
NC
Write Protect (WP) - All write operations can be disabled
by maintaining WP > VIH.
GND
NoConnects(NC)-Thenoconnectinputsareunusedby
the SMS8198; however, to insure proper operation they
can be unconnected or tied to ground. They must not be
2036 T PCon 2.0
tied to VCC
.
ENDURANCE AND DATA RETENTION
The SMS8198 is designed for applications requiring up to
100,000 erase/write cycles and unlimited read cycles. It
provides 100 years of secure data retention, with or
without power applied, after the execution of 100,000
PIN NAMES
SDA Serial Data I/O
erase/write cycles.
SCL
TRI_RESET#
GND
Serial Clock Input
Reset Output
Ground
RESET CONTROLLER DESCRIPTION
VCC
WP
NC
Supply Voltage
Write Protect
No Connect
The device provides a precise reset output to a
microcontroller and it’s associated circuitry ensuring cor-
rect system operation during power-up/down conditions
and brownout situations. The output is open drain, allow-
ing control of the reset function by multiple devices.
Duringpower-uptheresetoutputremainsinafixedactive
state until VCC passes through the reset threshold and
remains above the threshold for tPURST. The reset output
isvalidwheneverVCC isequaltoorgreaterthan1V. IfVCC
falls below the threshold for more than tGLITCH the device
will immediately generate a reset and drive the output.
PIN DESCRIPTIONS
Serial Clock (SCL) - The SCL input is used to clock data
into and out of the device. In the WRITE mode, data must
remainstablewhileSCLisHIGH.IntheREADmode,data
is clocked out on the falling edge of SCL.
The reset pin is an I/O; therefore, forcing the pin to the
active state can also manually reset the device. Because
the I/O needs to be an open drain, the internal timer can
only be triggered by the leading edge of the input. The
resultingresetoutputwilleitherbetPURST,ortheexternally
appliedresetsignal,whicheverislonger.Thiscanprovide
an affective debounce or reset signal extender solution.
Serial Data (SDA) - The SDA pin is a bidirectional pin
used to transfer data into and out of the device. Data may
changeonlywhenSCLisLOW,exceptSTARTandSTOP
conditions. It is an open-drain output and may be wire-
ORed with any number of open-drain or open-collector
outputs.
2036 5.0 4/18/00
4
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
