Datasheet
LTC1696
1
, LTC and LT are registered trademarks of Linear Technology Corporation.
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±2% Overvoltage Threshold Accuracy
■
Low Profile (1mm) ThinSOT
TM
Package
■
Gate Drive for SCR Crowbar or External N-Channel
Disconnect MOSFET
■
Monitors Two Output Voltages
■
Senses Output Voltages from 0.8V to 24V
■
Wide Supply Range: 2.7V to 27V
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Multifunction TIMER/RESET Pin
Overvoltage Protection
Controller
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Telecommunication Systems
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Computer Systems
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Industrial Control Systems
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Notebook Computers
SCR Crowbar
DESCRIPTIO
U
FEATURES
APPLICATIO S
U
TYPICAL APPLICATIO
U
The LTC
®
1696 is a standalone power supply overvoltage
monitor and protection device designed to protect a power
supply load in the event of an overvoltage fault. It monitors
two adjustable output voltages. If an overvoltage condi-
tion is detected, the output drives either an external SCR
crowbar or turns off external back-to-back N-channel
MOSFETs, thereby, disconnecting the input voltage from
the power supply.
Pin 6 offers three functions. By connecting a capacitor to
this pin, the internal glitch filter time delay can be pro-
grammed. Without the capacitor, the default time delay is
determined by an internal capacitor. This pin also serves
as a reset input to clear the internal latch after an overvolt-
age fault condition. By pulling it high, the OUT pin is
activated if the FB1 and FB2 voltages remain below the trip
threshold.
The LTC1696 is available in the low profile (1mm) ThinSOT
package.
C1
1nF
6
V
OUT2
5V
V
OUT1
3.3V
5
4
1696 TA01
1
2
3
SCR
2N6507
LTC1696
RESET
Q1
2N7002
FB1
GND
V
CC
FB2
OUT
TIMER/
RESET
R1
44.2k
1%
V
CC
12V
R2
137k
1%
R3
44.2k
1%
R4
232k
1%
C2
0.1µF
POWER
SUPPLY
FB1
0.5V/DIV
TIMER/RESET
2V/DIV
I
OUT
20mA/DIV
ThinSOT is a trademark of Linear Technology Corporation.
100µs/DIV
1696 TA02
Overvoltage Response
C1 = 1nF