Pin Description

Pin

Name

Function

1

PGND

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

2

FB1

Buck output voltage feedback input.

3V

C1

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

amplifier.

4V

BG

Bandgap connection.

5

SS2

Boost soft start pin.

6V

C2

Boost compensation network connection. Connected to the output of the voltage error

amplifier.

7

FB2

Boost output voltage feedback input.

8

AGND

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

9

AGND

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

10

PGND

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

11

PGND

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

12

PGND

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

13

SW2

Boost power switch input. Switch connected between SW2 pins and PGND pins. SW2

pins should be connected directly together at the device.

14

SW2

Boost power switch input. Switch connected between SW2 pins and PGND pins. SW2

pins should be connected directly together at the device.

15

SW2

Boost power switch input. Switch connected between SW2 pins and PGND pins. SW2

pins should be connected directly together at the device.

16

V

IN

Analog power input. V

17

V

IN

Analog power input. V

18

SHDN2

Shutdown pin for Boost converter. Active low.

19

FSLCT

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

300kHz and 600kHz.

20

SS1

Buck soft start pin.

21

SHDN1

Shutdown pin for Buck converter. Active low.

22

CB1

Buck converter bootstrap capacitor connection.

23

V

IN

Analog power input. V

24

SW1

Buck power switch input. Switch connected between V

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