TL7700A Series
July 2000
SUPPLY VOLTAGE SUPERVISORS
®
.POWER-ON RESET GENERATOR
.AUTOMATIC RESET GENERATION AFTER
VOLTAGE DROP
.WIDE SUPPLY VOLTAGE RANGE ... 3V TO
18V
.PRECISION VOLTAGE SENSOR
.TEMPERATURE-COMPENSATED VOLTAGE
REFERENCE
.TRUE AND COMPLEMENT RESET OUTPUTS
.EXTERNALLY ADJUSTABLE PULSE WIDTH N
Minidip
DESCRIPTION
The TL7700A series are monolithic supply voltage
supervisor IC’s specifically designed for use as reset
controllers in microcomputer and microprocessor
systems. During power-up the device tests the sup-
ply v olt ag e and k eeps the RESET and RESET ou t-
puts active (high and low, respectively) as long as
th e supp ly volt age h as no t reac hed it s n omina l vol t-
age va lue. Tak ing RESIN low has the same effect.
To ensure that the microcomputer system has reset,
the TL7700A then initiates an internal time count
that delays the return of the reset outputs to their in-
active states. Since the time delay for most micro-
computers and microprocessors is in the order of
se ve ral machine cycles, the de vi ce internal time de-
lay is determined by an external capacitor con-
nec t ed to t he CT inp ut (pi n 3) .
tpo = 1. 3 x 104 x CT
Where : CT is in fara ds (F) and tpo in seconds (s). In
addition, when the supply voltage drops below the
nominal value, the outputs will be active until the
su pply v olt ag e re t ur ns to the nom ina l v alue. A n ex-
ternal capacitor (typically 0.1 µF) must be connected
to the RE F output (pi n 1) to re duc e the infl uenc e of
fa st tra ns ients in th e su ppl y v ol ta ge.
T he TL7700 A I ser ies is c har ac t eriz ed f o r o per at ion
from – 25 oC to 85oC ; the T L770 0AC seri es is c har-
a c terize d f rom 0oC to 70oC.
D
SO8
ORDERING NUMBERS
Temperature Range Minidip S08
0 to 70 oC TL77XXACP TL77XXACD
-25 to 85oC TL77XXAIP TL77XXAID
PIN CONNECTION (top view)
1/7
Obsolete Product(s) - Obsolete Product(s) Obsolete Product(s) - Obsolete Product(s) Obsolete Product(s) - Obsolete Product(s)