Pin Descriptions

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

Buck 1 output voltage feedback input.

5V

C1

Buck 1 compensation network connection. Connected to the output of the voltage error

amplifier.

6V

BG

Bandgap connection.

7V

C2

Buck 2 compensation network connection. Connected to the output of the voltage error

amplifier.

8

FB2

Buck 2 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

Buck 2 power switch input. Switch connected between V

14

V

IN

Analog power input. All V

together directly at the part.

15

V

IN

Analog power input. All V

together directly at the part.

16

CB2

Buck 2 converter bootstrap capacitor connection.

17

SHDN2

Shutdown pin for Buck 2 converter. Active low.

18

SS2

Buck 2 soft start pin.

19

FSLCT

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

300kHz and 600kHz.

20

SS1

Buck 1 soft start pin.

21

SHDN1

Shutdown pin for Buck 1 converter. Active low.

22

CB1

Buck 1 converter bootstrap capacitor connection.

23

V

IN

Analog power input. All V

together directly at the part.

24

SW1

Buck 1 power switch input. Switch connected between V

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