LTC1696

1

, LTC and LT are registered trademarks of Linear Technology Corporation.

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±2% Overvoltage Threshold Accuracy

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Low Profile (1mm) ThinSOT

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Gate Drive for SCR Crowbar or External N-Channel

Disconnect MOSFET

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Monitors Two Output Voltages

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Senses Output Voltages from 0.8V to 24V

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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

FEATURES

APPLICATIO S

TYPICAL APPLICATIO

The LTC

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

5V

3.3V

5

4

1696 TA01

1

2

3

SCR

2N6507

LTC1696

RESET

Q1

2N7002

FB1

GND

FB2

OUT

TIMER/

RESET

R1

44.2k

1%

12V

R2

137k

1%

R3

44.2k

1%

R4

232k

1%

C2

0.1

µF

POWER

SUPPLY

FB1

0.5V/DIV

TIMER/RESET

2V/DIV

20mA/DIV

ThinSOT is a trademark of Linear Technology Corporation.

100

µs/DIV

1696 TA02

Overvoltage Response

C1 = 1nF