LTC1696

14

1696fb

For more information www.linear.com/LTC1696



LINEAR TECHNOLOGY CORPORATION 2001

LT 1214 REV B • PRINTED IN USA

LinearTechnology Corporation

1630 McCarthy Blvd., Milpitas, CA 95035-7417

RELATED PARTS

TYPICAL APPLICATION

PART NUMBER DESCRIPTION

COMMENTS

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60V, Low IQ, Dual 2-Phase Synchronous Step-Down DC/DC

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LTC3855

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with Diff Amp and DCR Temperature Compensation

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LTC3861

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LTC3875

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LTC3866

Sub Milli Ohm Current Mode Synchronous Step-Down

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LTC3765/

LTC3766

Forward No Opto Synchronous Controller Chip Set

with Active Clamp Reset

Direct Flux Limit, Supports Self Starting Secondary Forward Control

LTC3722/

LTC3722-2

Synchronous Full Bridge Controllers

Adaptive or Manual Delay Control for Zero Voltage Switching,

Adjustable Synchronous Rectification Timing

External Triggering

The LTC1696 has a feature which allows the output to

be latched into an active high state by pulling the TIMER/

RESET pin high even if both the feedback voltages at the

FB1 and FB2 pins are below the trip threshold of the in-

ternal comparator. The output is then reset by pulling the

TIMER/RESET pin low. Figure 4 shows a circuit that uses

the external triggering function of the LTC1696

C1

1nF

6

5

4

1696 F04

1

2

3

LTC1696

RESET

5V

1.8V

Q2

2N7002

TRIGGER

Q3

2N7002

D1

1N4148

FB1

GND

FB2

OUT

TIMER/

RESET

R1

44.2k

1%

1.5V

3.3V

R2

38.3k

1%

R3

44.2k

1%

R5

6.8k

5%

Q1

2N7002

N-CHANNEL

×2

PRIMARY

INPUT

SUPPLY

R4

54.9k

1%

C2

0.1µF

POWER MANAGEMENT

CONTOLLER

Figure 4. External Triggering