Pin Description

Pin

Name

Function

1

PGND

Power ground. PGND and AGND pins must be connected together directly at the part.

2

PGND

Power ground. PGND and AGND pins must be connected together directly at the part.

3

AGND

Analog ground. PGND and AGND pins must be connected together directly at the part.

4

FB1

Fixed buck output voltage feedback input.

5V

C1

Fixed buck compensation network connection. Connected to the output of the voltage

error amplifier.

6V

BG

Bandgap connection.

7V

C2

Adjustable buck compensation network connection. Connected to the output of the voltage

error amplifier.

8

FB2

Adjustable buck output voltage feedback input.

9

AGND

Analog ground. PGND and AGND pins must be connected together directly at the part.

10

AGND

Analog ground. PGND and AGND pins must be connected together directly at the part.

11

PGND

Power ground. PGND and AGND pins must be connected together directly at the part.

12

PGND

Power ground. PGND and AGND pins must be connected together directly at the part.

13

SW2

Adjustable buck power switch input. Switch connected between V

14

V

IN

Analog power input. V

15

V

IN

Analog power input. V

16

CB2

Adjustable buck converter bootstrap capacitor connection.

17

SHDN2

Shutdown pin for adjustable buck converter. Active low.

18

SS2

Adjustable buck soft start pin.

19

FSLCT

Switching frequency select input. Use a resistor to set the frequency anywhere between

300kHz and 600kHz.

20

SS1

Fixed buck soft start pin.

21

SHDN1

Shutdown pin for fixed buck converter. Active low.

22

CB1

Fixed buck converter bootstrap capacitor connection.

23

V

IN

Analog power input. V

24

SW1

Fixed buck power switch input. Switch connected between V

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