AN2148 - APPLICATION NOTE

3/8

The carkit connection architecture is shown in the two figures below. Figure 2 shows the interface

between a phone and a carkit using standard Mini-USB cable.

Figure 3 shows the interface between a phone and a carkit using captive cable with five wires.

Figure 2 : Carkit Four-Wire Interface

Figure 3 : Carkit Five-Wire Interface

V

BUS

D-

D+

ID

GND

SHLD

D+

D-

ID

SDA

SCL

RCV

OE_TP_INT/

SE0_VM

DAT_VP

SDA

SCL

RCV

OE_N

VP

VM

RXD

TXD

5V_IN

Power Management

USB-OTG Controller

Phone Processor

USB-OTG Transceiver

Mini-AB

Receptable

SPKR_MIC

SPKR_L

Mini-A

Receptable

V

BUS

D-

D+

ID

GND

SHLD

V

BUS

D-

D+

ID

GND

SHLD

V

BUS

D-

D+

ID

GND

SHLD

SPKR_MIC

SPKR_L

Standard Mini-USB Cable

Carkit Amplifier

CMR

RXD_SDA

TXD_SCL

Carkit Control

Voltage Regulator

5V_OUT

V

BUS

D-

D+

ID

GND

SHLD

D+

D-

ID

SDA

SCL

RCV

OE_TP_INT/

SE0_VM

DAT_VP

SDA

SCL

RCV

OE_N

VP

VM

RXD

TXD

5V_IN

Power Management

USB-OTG Controller

Phone Processor

USB-OTG Transceiver

Mini-AB

Receptable

SPKR_MIC

SPKR_L

V

BUS

D-

D+

ID

GND

SHLD

SPKR_MIC

SPKR_L

Carkit Amplifier

CMR

RXD_SDA

TXD_SCL

Carkit Control

Voltage Regulator

5V_OUT