MAX14531E–MAX14534E
USB 2.0 Hi-Speed and Audio Switches with
Negative Signal Capability and ±15kV ESD
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Detailed Description
The MAX14531E–MAX14534E are high ESD-protected
single DP3T switches that operate from a +2.7V to +5.5V
supply and are designed to multiplex USB 2.0 Hi-Speed
signals and AC-coupled analog signals. These switches
combine the low on-capacitance (C
ON
) and low on-resis-
tance (R
ON
) necessary for high-performance switching
applications. These devices also meet the requirements
for USB low-speed and full-speed signaling. The nega-
tive signal capability of all three channels allows signals
below ground to pass through without distortion.
Analog Signal Levels
The MAX14531E–MAX14534E are bidirectional, allow-
ing UAX_, UAY_, UAZ_, and COM_ to be configured as
either inputs or outputs. Note that UAX_, UAY_, and
UAZ_ are only protected against ESD up to ±2kV
(Human Body Model) and may require additional ESD
protection if used as outputs. These devices feature a
charge pump that generates a negative supply to allow
analog signals as low as -2.0V applied to UAX_, UAY_,
UAZ_, or COM_. The negative charge pump is only
active when the part is enabled (CB0 or CB1 = 1).
Connect negative signals to UAX_, UAY_, UAZ_, or
COM_ only when the device is enabled.
VBUS Detection
The MAX14531E–MAX14534E feature a VBUS detec-
tion input (CB0) that connects COM_ to UAX_ when
V
CB0
exceeds the VBUS detection threshold (V
VBDET
)
(see the
Functional Diagram/Truth Table
). Note that the
MAX14531E requires an external pulldown resistor
when using this function.
Digital Control Inputs
The MAX14531E–MAX14534E provide control logic
inputs, CB0 and CB1, to control the switch position as
shown in the
Functional Diagram/Truth Table
. Drive
CB_ rail-to-rail to minimize power consumption.
Shutdown Mode
The MAX14531E–MAX14534E feature a shutdown
mode to reduce the supply current to less than 1µA and
place the switches in high impedance. Drive both CB0
and CB1 low to place the devices in shutdown mode
(see the
Functional Diagram/Truth Table
.)
Click-and-Pop Suppression
The switched 100Ω shunt resistors on the MAX14532E/
MAX14534E automatically discharge any capacitance
at the UAZ_ (MAX14532E) or UAY_ and UAZ_
(MAX14534E) inputs when they are unconnected from
COM_ (see the
Functional Diagram/Truth Table
). This
reduces audio click-and-pop sounds that may occur
when switching to audio sources.
Applications Information
Extended ESD Protection
ESD-protection structures are incorporated on all pins
to protect against electrostatic discharges up to ±2kV
(Human Body Model) encountered during handling and
assembly. COM1 and COM2 are further protected
against ESD up to ±15kV (Human Body Model) without
damage. The ESD structures withstand high ESD both
in normal operation and when the device is powered
down. After an ESD event, the MAX14531E–
MAX14534E continue to function without latchup.
ESD Test Conditions
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents
test setup, test methodology, and test results.
Human Body Model
Figure 4 shows the Human Body Model, and Figure 5
shows the current waveform it generates when discharged
into a low impedance. This model consists of a 100pF
capacitor charged to the ESD voltage of interest that is
then discharged into the device through a 1.5kΩ resistor.
