LT8686S

22

Rev. 0

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TYPICAL APPLICATIONS

2.2µF

2.2µF

4.7µF

1.0µF

0.1µF

0.1µF

1M

47µF

191k

4.7pF

0.1µF 0.68µH

649k

47µF

523k

10pF

0.1µF 0.56µH

412k

47µF

825k

10pF

26.1k

22.6k

0.1µF

1.5µH**

976k

47µF

309k

4.7pF

1.8µH**

10nF

10nF

BST3

SW3

FB3

BST4

SW4

FB4

BIAS

BST1

SW1

FB1

BST2

SW2

FB2

EN/UVLO

EN2

VIN1

VIN2

EN3

EN4

VIN3

VIN4

VIN

6V TO 42V

PG4

PG3

PG2

PG1

TRK/SS4

TRK/SS3

TRK/SS2

TRK/SS1

RT

SYNC/MODE

OUT1

5V, 2A*

INTVCC

OUT4

1.2V, 2A

OUT3

1.8V, 2A

GND

OUT2

3.3V, 2A

LT8686S

OUT1

**INDUCTOR VALUES CHOSEN FOR VIN = 12V

8686S TA02a

*CURRENT AVAILABLE FROM OUT1: 2A – IVIN3 – IVIN4 – IBIAS

START-UP SEQUENCE:

VIN HIGH ENABLES HV CHANNELS

HV CHANNELS TRACK RATIOMETRICALLY

VOUT1 HIGH ENABLES LV CHANNELS

LV CHANNELS TRACK RATIOMETRICALLY

1ms/DIV

VOUT1

2V/DIV

VIN

10V/DIV

VOUT3

1V/DIV

VOUT2

2V/DIV

VOUT4

1V/DIV

8686S TA02b

Start-Up Sequencing

42V Input, Quad Output 2MHz Step-Down Regulator with Spread Spectrum and Ratiometric Output Start-Up

(Details of Front-Page Application)