STWLC04

Pin configuration

DocID029626 Rev 2

5/18

Pin name

Pin position

Description

VSUPS

A7, C6

Sensing terminal of the external current sensing resistor

RESL

A6

Sensing terminal of the external current sensing resistor

VOUT

D5

Step-down output voltage

VFB

A5

Step-down feedback input

FBGND

B6

Ground connection of the resistor feedback divider for step-down

converter

LX

A11, B11, B10

Step-down converter coil connection

NTCRX

A3

Comparator input for RX coil temperature sensing

NTC thermistor has to be placed close to RX coil

VA

A4

LDO1 output to filtering capacitor. ADC supply and sensitive analog

circuitries are connected to this LDO; any external circuit cannot be

connected to this node

VCORE

F2

LDO2 output to filtering capacitor. The microcontroller core and logic

supply. VCORE voltage can be used as a reference voltage for the

RX coil NTC divider

V5V

A9, B9

LDO3 output to filtering capacitor

VIO

G1

VIO, power supply for the digital interface, can be connected to

VCORE or provided externally

SCL

D1

SDA

D4

GPIO0

D6

General purpose push-pull I/O pin. This function depends on firmware

configuration

GPIO1

E5

General purpose push-pull I/O pin. This function depends on firmware

configuration

GPIO2

E4

General purpose push-pull I/O pin. This function depends on firmware

configuration

GPIO3

E1

Open drain output only pin. This function depends on firmware

configuration

RESET

D2

Chip reset input, active low

INT

C3

Open drain interrupt output to the host platform

RPGND

D8, D9, D10,

D11

Rectifier power ground

BPGND

C8, C9, C10,

C11

Step-down converter power ground

GND

G2, F3

Digital ground

AGND

B4, C4, B5, C5

Analog ground

VEXT

A10

Detection of the external power supply voltage

– adapter/USB

voltage, 30 V spike tolerant

SWDRV

D7

External P-channel switch control to connect the adapter/USB voltage

to VOUT

USBOK

C2

Digital input for the USBOK signal from platforms

COMP

C7

Step-down converter soft-start capacitor connection