LTC1696

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1696fb

For more information www.linear.com/LTC1696

TYPICAL APPLICATION

FEATURES

DESCRIPTION

Overvoltage Protection

Controller

The LTC®1696 is a standalone power supply overvolt-

age 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

condition 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

programmed. 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

overvoltage 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.

APPLICATIONS

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±2% Overvoltage Threshold Accuracy

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n

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

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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

L

, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear

Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation.All other

trademarks are the property of their respective owners. .

SCR Crowbar

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

0.1µF

POWER

SUPPLY

FB1

0.5V/DIV

TIMER/RESET

2V/DIV

20mA/DIV

100µs/DIV

1696 TA02

Overvoltage Response

C1 = 1nF