Table 5-1. Pin Functions (continued)

PIN

I/O

TYPE

DESCRIPTION

CONNECTION

IF NOT USED

NAME

NO.

PGND_B3BS

T

12

—

Ground

Power ground for BUCK3 and BOOST.

Ground

PVIN_B3

13

—

Power

Power input for BUCK3. The separate power pins PVIN_Bxx are not connected

together internally – PVIN_Bxx and VCCA pins must be connected together in the

application and be locally bypassed.

System supply

SW_B3

14

—

Analog

BUCK3 switch node.

Floating

ENABLE

15

I

Digital

Programmable ENABLE signal.

Not applicable

nERR/GPO2

16

I

Digital

Primary function: System MCU Error Monitoring Input.

Ground

O

Digital

Alternative programmable function: General Purpose Output signal (GPO2).

Floating

O

Digital

Alternative programmable function: Fault Communication Output signal (FAULT2). Floating

FB_B3

17

—

Analog

Output voltage feedback (positive) for BUCK3.

Ground

VOUT_VLDO

18

—

Power

LDO regulator filter node. LDO is used for internal purposes. No external load

allowed.

-

AGND

19

—

Ground

Ground.

Ground

VCCA

20

—

Power

Supply voltage for internal LDO. VCCA and PVIN_Bxx pins must be connected

together in the application and be locally bypassed.

System supply

FB_B2

21

—

Analog

Output voltage feedback (positive) for BUCK2.

Ground

VMON1/

GPO1

22

—

Analog

Voltage monitoring input.

Ground

O

Digital

Alternative programmable function: General Purpose Output signal (GPO1).

Floating

O

Digital

Alternative programmable function: Fault Communication Output signal (FAULT1). Floating

O

Digital

Alternative programmable function: CAN PHY control (CAN_DIS).

Floating

SYNCCLKIN 23

I

Digital

External clock input.

Ground

SW_B2

24

—

Analog

BUCK2 switch node.

Floating

PVIN_B2

25

—

Power

Power input for BUCK2. The separate power pins PVIN_Bxx are not connected

together internally – PVIN_Bxx and VCCA pins must be connected together in the

application and be locally bypassed.

System supply

PGND_B12

26

—

Ground

Power ground for BUCK1 and BUCK2.

Ground

PVIN_B1

27

—

Power

Power input for BUCK1. The separate power pins PVIN_Bxx are not connected

together internally – PVIN_Bxx and VCCA pins must be connected together in the

application and be locally bypassed.

System supply

SW_B1

28

—

Analog

BUCK1 switch node.

Floating

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LP87745

SNVSCH5 – NOVEMBER 2023

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