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STMicroelectronics |
TL7700 A Series
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
Min idip
DESCRIPTION
The TL7700Aseriesaremonolithicintegratedcircuit
supplyvoltagesupervisorsspecifically desi-gnedfor
use as reset controllers in microcomputer and mi-
croprocessor systems. During power-up the device
tests the supply voltage and keeps the RESET and
RESET outputs active (high and low, respectively)
as long as the supply voltage has not reached its
nominal voltage value. Taking RESIN low has the
same effect. To ensure that the microcomputer sys-
tem hasreset, the TL7700Athen initiates aninternal
time delay that delays the return of the reset outputs
to theirinactivestates. Since the timedelay for most
microcomputersand microprocessors is in the order
of several machine cycles, the device internal time
delay is determined by an external time delay is de-
termined by an external capacitor connected to the
CT input (pin 3).
td = 1.3 x 104 x CT
Where : CT is in farads (F) and td in seconds (s). In
addition, when the supply voltage drops below the
nominal value, the outputs will be active until the
supply voltage returns to the nominal value. An ex-
ternalcapacitor(typically0.1 µF) must be connected
to the REF output (pin 1) to reduce the influence of
fast transients in the supply voltage.
The TL7700AI series is characterized for operation
from – 25oC to 85oC ; the TL7700AC series is char-
acterized from 0oC to 70oC.
D
SO8
ORDERING NUMBERS
Temperature Range Minidip
0 to 70oC
TL77XXACP
-25 to 85oC
TL77XXAIP
S08
TL77XXACD
TL77XXAID
PIN CONNECTION (top view)
August 1996
1/7
TL7700A Series
BLOCK DIAGRAM
* TL7702A R1 = 0Ω, R2 = open ; TL7705A R1 = 7.8 K Ω, R2 = 10kΩ ; TL7709A R1 = 19.7 KΩ, R2 = 10kΩ ;
TL7712A R1 = 32.7kΩ, R2 = 10kΩ ; TL7715A R1 = 43.4 KΩ, R2 = 10kΩ.
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
VS Supply Voltage, VCC - (see note 1)
Vi Input Voltage Range at RESIN
Vi Input Voltage at SENSE :
TL7702A (see note 2)
TL7705A
TL7709A
TL7712A
TL7715A
IOH
IOL
Tamb
High-level Output Current at RESET
Low-level Output Current at RESET
Operating Free-air Temperature Range :
TL77XXAI
TL77XXAC
Tstg Storage Temperature Range
Notes : 1. All voltage values are with respect to the network ground terminal
2. For the TL7700A, the voltage applied to the SENSE terminal must never exceed Vs.
THERMAL DATA
Symbol
Parameter
Rth j-amb Thermal Resistance Junction-ambient
Max.
Value
20
-0.3 to 20
-0.3 to 6
-0.3 to 10
-0.3 to 15
-0.3 to 20
-0.3 to 20
-30
30
-25 to 85
0 to 70
-65 to 150
Value
120
Unit
V
V
V
mA
mA
oC
oC
Unit
oC/W
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
Min.
Max.
Unit
VS Supply Voltage
3.6 18
V
VIH High-level Input Voltage at RESIN
VIL Low-level Input Voltage at RESIN
2V
0.6 V
Vi Voltage at Sense Input
TL7702A
TL7705A
TL7709A
TL7712A
TL7715A
0 See note 3 V
0 10
0 15
0 20
0 20
IOH High-level Output Current at RESET
-16 mA
IOL
Tamb
Low-level Output Current at RESET
Operating Free-air Temperature Range TL77-AI
TL77-AC
16 mA
-25 85
0 70
oC
Note : 3. For proper operation of the TL7702A, the voltage applied to the SENSE terminal should not exceed Vs - 1V or 6V, which ever is less.
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