9

FN6817.3

May 4, 2009

Block Diagram

Detailed Description

The ISL54217 device consists of dual SP3T (single

pole/triple throw) analog switches. It operates from a single

DC power supply in the range of 2.7V to 4.6V. It was

designed to function as differential 3-to-1 multiplexer to

select between two different USB differential data signals

and audio L and R stereo signals. It comes in a tiny µTQFN

and TQFN packages for use in MP3 players, PDAs, cell

phones, and other personal media players.

A device consists of two 2.3

Ω audio switches and four 6.2Ω

USB switches. The audio switches can accept signals that

swing below ground. They were designed to pass audio left

and right stereo signals, that are ground referenced, with

minimal distortion. The USB switches were designed to pass

high-speed USB differential data signals with minimal edge

and phase distortion.

The ISL54217 was specifically designed for MP3 players,

personal media players and cellphone applications that need

FIGURE 9. CLICK AND POP TEST CIRCUIT

C

GND

L

COM-

AUDIO PRECISION

C0, C1

SYSTEM II CASCADE

ANALYZER

R

COM+

CHA

CHB

CLICK

AND

POP

Set Audio Analyzer for Peak Detection, 32 Samples/Sec, Aweighted Filter, Manual Range 1X/Y, Units to dBV

3.3V

SQUARE WAVE

CLICK/

ISL54217

USB

TRANSCEIVER

HIGH-SPEED

AUDIO

COM -

COM +

C1

GND

1D+

1D-

R

L

VDD

C0

LOGIC CONTROL

µCONTROLLER

CODEC

3.3V

2D-

USB

4M

Ω

50k

Ω

HIGH-SPEED

TRANSCEIVER

2D+

50k

Ω

1k

Ω

POP

#2

#1

OR

UART

TRANSCEIVER

ISL54217