RT7273 参数 Datasheet PDF下载

RT7273

Typical Application Circuit

V

IN

12V

32, 33, 34

C33

10µF

C23

22µF

13

C10

10µF

18

C17

10µF

C9

10µF

C26

10µF

VINR

VIN1

VIN2

RT7273

LX1

14, 15

BOOT1 12

C7

100nF

L1

4.7µH

R9

40.2k

C24

100nF

L2

4.7µH

R12

80.8k

C13

470pF

V

OUT1

1.2V/3A

C3

22µF

C18

22µF

38 VIN3

28

PVCC

29 VCC

8 COMP1

10 RLIM1

9 SS1

11 EN1

FB1 7

BOOT2 19

V

OUT2

1.8V/2A

C32

470pF

C16

22µF

C21

22µF

C27

3.3µF

LX2

16, 17

R5

20k

C2

4.7nF

C19

NC

FB2 24

BOOT3 39

R1

40.2k

C31

100nF

L3

4.7µH

R15

32.4k

R1

51k

C4

4.7nF

R17

20k

C28

4.7nF

C20

NC

R16

75k

C25

4.7nF

C5

4.7nF

23 COMP2

21 RLIM2

22 SS2

20 EN2

C29

4.7nF

V

OUT3

3.3V/2A

C15

470pF

C11

22µF

C22

22µF

LX3

36, 37

FB3 4

V

CC

R18

100k

R20

40.2k

R13

12.7k

R3

20k

C1

4.7nF

C14

NC

R4

82k

C3

4.7nF

C6

4.7nF

3 COMP3

1 RLIM3

2 SS3

40 EN3

PGOOD

27

PGOOD

Input Signal

SYNC 5

LOWP 25

ROSC 6

GND

26, 30, 31, 35,

41 (Exposed Pad)

R7

383k

Table 1. Suggested Component Values for CH1 (V

IN

= 12V, f

S

= 500kHz)

V

OUT

(V)

1.2

1.8

3.3

5

7

R9 (k)

40.2

40.2

40.2

40.2

40.2

R12 (k)

80.8

32.4

12.7

7.6

5.2

C13 (pF)

470

470

470

470

470

R5 (k)

20

20

20

24

24

C2 (nF)

4.7

4.7

4.7

5.6

5.6

L1 (H)

4.7

4.7

4.7

6.8

6.8

C3 (F)

44

44

44

44

44

Note 5.

The suggested component values can be applied to CH 2 and CH 3 as well.

Note 6.

Above values are fully tested for stable operation. When making changes to output capacitors or switching frequency,

please follow the guidelines in the application section.

Copyright

©

2014 Richtek Technology Corporation. All rights reserved.

is a registered trademark of Richtek Technology Corporation.

DS7273-04

October 2014

www.richtek.com

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