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AN1358.0

June 23, 2008

ISL54207 device will sense the VBUS voltage from the 
computer, and will go into USB mode. High Speed USB 
signals can be passed between J4 and J12.

An “A” type USB receptacle labeled USB TO DEVICE (J12) 
is located on the right underside of the board. The USB 
device can be plugged directly into this receptacle or through 
a standard USB cable. 

In USB mode the USB host controller and USB device will 
be connected through the internal USB switches of the IC. 
The USB switches are bi-directional which allow the host 
(computer) and downstream USB device to both send and 
receive data.

JP1 and JP2 permit the connection of differential probes for 
monitoring of the USB signals. JP1 is used for monitoring on 
the device side. JP2 is used for monitoring on the host side. 
In addition, BNC connectors J9 (D-) and J10 (D+) can be 
connected in parallel to J12 for monitoring the USB signals 
on the device side using an oscilloscope. Normally, J9 and 
J10 are not connected to the USB signal path. If the user 
requires BNC connections to the USB signals on the device 
side, then R

1

 and R

2

 on the evaluation board can be 

populated with 0

Ω

 

resistors. R

1

 and R

2

 are located between 

the J9 and J10 BNC connectors.

Note: Before connecting the USB host controller at 
connector J4, the A/V connections must be disconnected (or 
set to high impedance) from the VIDEO OUT and MONO 
AUDIO OUT connectors (J5-J8). This will prevent the 
audio/video load from interfering with USB signal 
transmission.

Application

The main purpose of the ISL54207 device is to allow the use 
of a common USB and Audio/Video Connector in Personal 
Media Players and other portable battery-powered 
equipment. Either a TV monitor will be in the common 
connector to play video or a USB cable from a computer will 
be in the common connector to transmit digital data, such as 
music videos or MP3 songs into the memory of the Media 
Player.

Board Component Definitions

 

DESIGNATOR

DESCRIPTION

U1

ISL54207IRUZ IC

J1

Ground Connection

J2

V

DD

 Positive Connection

J3

VBUS Logic Input 

J4

“B” type USB Receptacle

J5, J6

VIDEO OUT Outputs

J7, J8

MONO AUDIO OUT Outputs

J9

USB (D-) BNC Connector

J10

USB (D+) BNC Connector

J11

CTRL Logic Input

J12

“A” type USB Receptacle

J13, J14

VIDEO IN Inputs

J15, J16

MONO AUDIO IN Inputs

JP1, JP2

D-/D+ Differential Probe Connection

Application Note 1358

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