ISL54217IRTZ Intersil, ISL54217IRTZ Datasheet - Page 11

• Manufacturer Part Number: ISL54217IRTZ
• Description: IC USB SWITCH DUAL SP3T 12TQFN
• Manufacturer: Intersil

Specifications of ISL54217IRTZ

• Function: USB Switch
• Circuit: 2 x SP3T
• On-state Resistance: 8 Ohm
• Voltage Supply Source: Single Supply
• Voltage - Supply, Single/dual (±): 2.7 V ~ 4.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 12-TQFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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 2.3Ω 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 to combine the stereo audio and USB data channels
into a single shared connector, thereby saving space and
component cost. The “Block Diagram” of this
functionality is shown on page 11.
The ISL54217 contains two logic control pins (C1 and C0)
that determine the state of the device. The part has the
following five states or modes of operation: All
SWITCHES OFF; USB1; USB2; Audio; and Audio Mute.
These states are discussed in detail in “Logic Control” on
page 12.
A detailed description of the various types of switches are
provided in “Audio Switches” beginning on page 11.
TRANSCEIVER
TRANSCEIVER
TRANSCEIVER
HIGH-SPEED
HIGH-SPEED
CODEC
UART
AUDIO
USB
USB
OR
#1
#2
11
2D-
2D+
1D-
1D+
L
R
CLICK/
POP
ISL54217
50kΩ
GND
LOGIC CONTROL
ISL54217
VDD
Audio Switches
The two audio switches (L, R) are 2.3Ω switches that can
pass signals that swing below ground.
Over a signal range of
VDD > 2.7V, these switches have an extremely low r
resistance variation. They can pass ground referenced
audio signals with very low distortion (<0.05% THD+N)
when delivering 15.6mW into a 32Ω headphone speaker
load. See Figures 20, 21, 22, 23 and 24 THD+N
performance curves.
Crosstalk between the L and R audio switches over the
frequency range of 20Hz to 20kHz when driving a 32Ω
load is <-88dB. These switches have excellent
off-isolation >105dB over the audio band when
connected to 32Ω loads and 77dB when connected to
20kΩ loads (In Audio Mute mode). See Figures 25 and
26 in “Typical Performance Curves” section beginning on
page 14.
The audio drivers should be connected at the L and R
side of the switch (pins 2 and 3) and the speaker loads
should be connected at the COM side of the switch (pins
7 and 8).
The switches have click and pop circuitry on the L and R
side that is activated when the part comes out of Audio
mode by taking the C1 and C0 logic pins low (All OFF
mode). The ISL54217 should be put in this mode before
powering down or powering up of the audio CODEC
drivers. In this mode the audio, USB1, USB2 switches will
be OPEN (OFF) and the audio click and pop circuitry will
be ON. The high off-isolation of the audio switches along
with the click and pop circuitry will isolate the transients
generated during power-up and power down of the audio
CODECs from getting through to the headphones thus
50kΩ
3.3V
1kΩ
4MΩ
COM +
COM -
C0
C1
±
1V (0.707V
µCONTROLLER
V
BUS
RMS
) with
June 17, 2010
FN6817.4
ON