ISL54220IRTZ Intersil, ISL54220IRTZ Datasheet - Page 9

• Manufacturer Part Number: ISL54220IRTZ
• Description: IC USB SWITCH DUAL SPDT 10TDFN
• Manufacturer: Intersil

Specifications of ISL54220IRTZ

• Function: USB Switch
• Circuit: 2 x SPDT
• On-state Resistance: 8 Ohm
• Voltage Supply Source: Single Supply
• Voltage - Supply, Single/dual (±): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 10-TDFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Application Block Diagram
Detailed Description
The ISL54220 device is a dual single pole/double throw
(SPDT) analog switch configured as a DPDT that operates
from a single DC power supply in the range of 2.7V to
5.5V.
It was designed to function as a dual 2-to-1 multiplexer
to select between two USB high-speed differential data
signals in portable battery powered products. It is offered
in a TDFN, MSOP, and a small µTQFN packages for use in
MP3 players, cameras, PDAs, cell phones, and other
personal media players. The device has an enable pin to
open all switches.
The part consists of four 6Ω high speed (HSx) switches.
These switches have high bandwidth and low capacitance
to pass USB high-speed (480Mbps) differential data
signals with minimal edge and phase distortion. They can
also swing from 0V to V
(12Mbps) differential data signals with minimal
distortion.
The ISL54220 was designed for MP3 players, cameras,
cell phones, and other personal media player applications
that have multiple high-speed or full-speed transceivers
sections and need to multiplex between these USB
sources to a single USB host (computer). A typical
application block diagram of this is shown on page 9.
A detailed description of the HS switches is provided in
the following section.
High-Speed (HSx) Switches
The HSx switches (HSD1-, HSD1+, HSD2-, HSD2+) are
bi-directional switches that can pass rail-to-rail signals.
When powered with a 3.3V supply, these switches have a
nominal r
with a r
ON
ON
flatness of 0.94Ω. The r
of 6Ω over the signal range of 0V to 400mV
VBUS
D-
D+
GND
DD
9
to pass USB full speed
ON
SEL
D-
D+
matching between
LOGIC CIRCUITRY
ISL54220
GND
VDD
ISL54220
HSD1+
HSD2+
HSD1-
HSD2-
OE
the HSD1 and HSD2 switches over this signal range is
only 0.12Ω, ensuring minimal impact by the switches to
USB high speed signal transitions. As the signal level
increases, the r
level of 3.3V, the switch resistance is nominally 129Ω.
See Figures 7, 8, 9, 10 in the “Typical Performance
Curves” beginning on page 11.
The HSx switches were specifically designed to pass USB
2.0 high-speed (480Mbps) differential signals in the
range of 0V to 400mV. They have low capacitance and
high bandwidth to pass the USB high-speed signals with
minimum edge and phase distortion to meet USB 2.0
high speed signal quality specifications. See Figure 11 in
the “Typical Performance Curves” on page 12 for USB
High-speed Eye Pattern taken with switch in the signal
path.
The HSx switches can also pass USB full-speed signals
(12Mbps) with minimal distortion and meet all the USB
requirements for USB 2.0 full-speed signaling. See
Figure 12 in the “Typical Performance Curves” on
page 13 for USB Full-speed Eye Pattern taken with
switch in the signal path.
The maximum normal operating signal range for the
HSx switches is from 0V to V
should not be allow to exceed the V
below ground by more than -0.3V for normal operation.
However, in the event that the USB 5.25V V
gets shorted to one or both of the D-/D+ pins, the
ISL54220 has special fault protection circuitry to prevent
damage to the ISL54220 part. The fault circuitry allows
the signal pins (D-, D+, HS1D-, HS1D+, HS2D-, HS2D+)
to be driven up to 5.5V while the V
the range of 0V to 5.5V. In this condition the part draws
< 500µA of current and causes no stress to the IC. In
addition when V
ON
DD
switch resistance increases. At signal
is at 0V (ground) all switches are OFF
PORTABLE MEDIA DEVICE
µCONTROLLER
TRANSCEIVER
TRANSCEIVER
HIGH_SPEED
HIGH-SPEED
FULL-SPEED
FULL-SPEED
USB
USB
OR
DD
#2
OR
#1
. The signal voltage
DD
DD
supply voltage is in
voltage rail or go
BUS
February 4, 2010
voltage
FN6819.1