ISL54206 Datasheet, PDF (7/13 Pages) Intersil Corporation – MP3/USB 2.0 High Speed Switch with Negative Signal Handling

Application Block Diagrams
ISL54206
VBUS
IN
COM-
VDD
ISL54206
LOGIC CIRCUITRY
4MΩ
CTRL
D-
D+
COM+
50kΩ L
R
50kΩ
GND
LOGIC CONTROL VIA MICRO-PROCESSOR
μCONTROLLER
USB
HIGH-SPEED
TRANSCEIVER
CODEC
VDD
VBUS
22kΩ
IN
4MΩ
ISL54206
LOGIC CIRCUITRY
4MΩ
COM-
CTRL
D-
D+
COM+
50kΩ L
R
50kΩ
μCONTROLLER
USB
HIGH-SPEED
TRANSCEIVER
CODEC
GND
LOGIC CONTROL VIA VBUS VOLTAGE FROM COMPUTER OR USB HUB
Detailed Description
The ISL54206 device is a dual single pole/double throw
(SPDT) analog switch device that can operate from a single
dc power supply in the range of 1.8V to 5.5V. It was
designed to function as a dual 2 to 1 multiplexer to select
between USB differential data signals and audio L and R
stereo signals. It comes in tiny µTQFN and TDFN packages
for use in MP3 players, PDAs, cell phones, and other
personal media players.
The part consists of two 3Ω audio switches and two 5Ω 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 ISL54206 was specifically designed for MP3 players,
cell phones and other personal media player applications
that need to combine the audio headphone jack and the
USB data connector into a single shared connector, thereby
saving space and component cost. Typical application block
diagrams of this functionality is shown above.
The ISL54206 has a single logic control pin (IN) that selects
between the audio switches and the USB switches. This pin
can be driven Low or High to switch between the audio
CODEC drivers and USB transceiver of the MP3 player or
cellphone. The ISL54206 also contains a logic control pin
(CTRL) that when driven Low while IN is Low, opens all
switches and puts the part into a low power state, drawing
typically 1nA of I_DD current.
A detailed description of the two types of switches is
provided in the sections following. The USB transmission
7
FN6409.0
December 18, 2006