MAX4904 Maxim, MAX4904 Datasheet - Page 8

• Manufacturer Part Number: MAX4904
• Description: The MAX4901–MAX4905 switches feature negative signal capability that allows signals below ground to pass through without distortion
• Manufacturer: Maxim

Low-R
Switches with Negative Rail Capability
The MAX4901–MAX4905 are low on-resistance, low-volt-
age, dual-SPST and single-SPDT analog switches that
operate from a +1.8V to +5.5V supply and are fully speci-
fied for nominal 3.0V applications. The devices feature a
negative signal capability that allows signals below
ground to pass through without distortion and
have break-before-make switching (MAX4903/
MAX4904/MAX4905).
The MAX4905 features a comparator that can be used for
headphone or mute detection. The comparator threshold
is internally generated to be approximately 1/3 of V
The MAX4902/MAX4904/MAX4905 feature an internal
shunt resistor to discharge any capacitance at NO_ and
NC connection points. This reduces the click-and-pop
sounds that occur when switching audio signals.
The MAX4901–MAX4905 logic inputs accept up to
+5.5V, regardless of supply voltage. For example, with
a +3.3V supply, IN_ can be driven low to GND and
high to +5.5V, allowing for mixing of logic levels in a
system. Driving IN_ rail-to-rail minimizes power
consumption. For a +1.8V supply voltage, the logic
thresholds are 0.5V (low) and 1.4V (high). For a +5V
supply voltage, the logic thresholds are 0.8V (low) and
2.0V (high).
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ON
Applications Information
DirectDrive
SOURCE
, Dual-SPST/Single-SPDT Clickless
Detailed Description
SOURCE
SOURCE
AUDIO
AUDIO
Digital Control Inputs
1
2
CMPO
NC
NO
CC
MAX4905
.
V
GND
CC
3
The on-resistance of the MAX4901–MAX4905 changes
very little for analog input signals across the entire sup-
ply-voltage range (see the Typical Operating
Characteristics). The switches are bidirectional.
The MAX4901–MAX4905 pass signals as low as V
5.5V, including signals below ground with minimal dis-
tortion. Note that there are shunt resistors on NO_ and
NC when they are unconnected to COM_ for the
MAX4902/MAX4904/MAX4905.
The MAX4905 includes a comparator that can be used
for mute and headphone detection functions. The posi-
tive terminal of the comparator is internally set to V
When the negative terminal (CMP-) is below the thresh-
old, the comparator output (CMPO) is a logic high.
The comparator threshold of V
of headphones because headphone audio signals are
typically biased to V
The 50Ω shunt resistors on the MAX4902/MAX4904/
MAX4905 automatically discharge any capacitance at
the NC or NO_ terminals when they are unconnected to
COM_. This reduces audio click-and-pop sounds that
occur when switching between audio sources.
CMP-
V
COM
IN
CC
V
CC
Typical Operating Circuit
(MAX4902/MAX4904/MAX4905)
MUTE
BUTTON
SPEAKER
CC
/ 2.
Comparator (MAX4905)
Analog Signal Levels
CC
/ 3 allows for detection
Shunt Resistor
CC
CC
/ 3.
-