TL7702B, TL7705B
SUPPLY-VOLTAGE SUPERVISORS
SLVS037H – SEPTEMBER 1989 – REVISED JULY 1999
TL77xxBC . . . D OR P PACKAGE
TL7705BM . . . JG PACKAGE
TL7705BQ . . . D PACKAGE
(TOP VIEW)
Power-On Reset Generator
Automatic Reset Generation After
Voltage Drop
REF
RESIN
CT
V
CC
1
2
3
4
8
7
6
5
RESET Output Defined From V
Precision Voltage Sensor
≥ 1 V
CC
SENSE
RESET
RESET
GND
Temperature-Compensated Voltage
Reference
TL7705BM . . . U PACKAGE
(TOP VIEW)
True and Complement Reset Outputs
Externally Adjustable Pulse Duration
1
NC •
NC
V
SENSE
RESET
RESET
10
9
2
REF
RESIN
CT
description
CC
3
4
5
8
The TL7702B and TL7705B are integrated-circuit
supply-voltage supervisors designed for use as
reset controllers in microcomputer and
microprocessor systems. The supply-voltage
supervisor monitors the supply for undervoltage
conditions at the SENSE input. During power up,
the RESET output becomes active (low) when
7
GND
6
NC – No internal connection
TL7705BM . . . FK PACKAGE
(TOP VIEW)
V
attains a value approaching 1 V. As V
CC
CC
approaches 3 V (assuming that SENSE is above
), the delay timer function activates a time
V
T+
delay, after which outputs RESET and RESET go
inactive (high and low, respectively). When an
undervoltage condition occurs during normal
operation, outputs RESET and RESET go active.
To ensure that a complete reset occurs, the reset
outputs remain active for a time delay after the
voltage at the SENSE input exceeds the
positive-going threshold value. The time delay is
3
2 1 20 19
18
NC
NC
RESIN
NC
4
5
6
7
8
SENSE
NC
17
16
15
14
RESET
NC
CT
NC
9 10 11 12 13
determined by the value of the external capacitor
4
C : t ≈ 2.6 × 10 × C , where C is in farads (F)
T d
T
T
and t is in seconds (s).
d
NC – No internal connection
An external capacitor (typically 0.1 µF) must be
connected to REF to reduce the influence of fast
transients in the supply voltage.
The TL7702BC and TL7705BC are characterized for operation from 0°C to 70°C. The TL7702BI and TL7705BI
are characterized for operation from –40°C to 85°C. The TL7705BQ is characterized for operation from –40°C
to 125°C. The TL7705BM is characterized for operation from –55°C to 125°C.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Copyright 1999, Texas Instruments Incorporated
On products compliant to MIL-PRF-38535, all parameters are tested
unless otherwise noted. On all other products, production
processing does not necessarily include testing of all parameters.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
1
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