
General Description
The MAX4735 quad-SPDT switch routes audio signals
in portable applications. Each channel has a 0.31Ω typical on-resistance, allowing the MAX4735 to drive 8Ω
loudspeakers with less than 0.02% distortion.
The MAX4735 is configured as a quad-SPDT switch with
two common control inputs. Each digital input controls
two pairs of SPDT switches. The switches are fully bidirectional, allowing both multiplexing and demultiplexing
operation. Break-before-make operation is guaranteed.
The device operates from a +1.6V to +3.6V supply and
over the extended -40°C to +85°C temperature range. It
is offered in both 16-pin 3mm x 3mm TQFN and TSSOP
packages.
Applications
Cell Phones
Digital Still Cameras
PDAs and Palmtop Devices
MP3 Players
Features
♦ Low 0.31Ω R
ON
♦ 0.06Ω On-Resistance Flatness
♦ Excellent 0.015Ω On-Resistance Matching
♦ Low 0.02% THD into 8Ω
♦ Low 0.015% THD into 32Ω
♦ Audio Signal Routing
♦ Space-Saving, 3mm x 3mm TQFN Package
♦ 1.8V Logic Compatible
MAX4735
Low-Voltage, 0.31Ω, Quad-SPDT Analog Switch
________________________________________________________________ Maxim Integrated Products 1
Pin Configurations
Ordering Information
1.6V TO 3.6V
INTERNAL
8Ω
SPEAKER
RING TONE/
MELODY IC
MAX4735
AUDIO
CODEC
V
CC
SYSTEM
CONTROLLER
EXTERNAL
8Ω OR 32Ω
SPEAKER
Typical Application Circuit
19-3581; Rev 0; 1/05
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Pin Configurations continued at end of data sheet.
Note: All products specified across the -40°C to +85°C temperature range.
MARK
TOP VIEW
NOTE: EXPOSED PADDLE CONNECTED TO GND.
INA
MAX4735
GND
TQFN
CC
V
NC4
INB
NO3
COM4
12
NO4
11
NC3
10
COM3
9
NC1
16 15 14 13
1
COM1
2
NO1
3
NC2
4
COM2
5678
NO2

MAX4735
Low-Voltage, 0.31Ω, Quad-SPDT Analog Switch
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC= 2.7V to 3.6V, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VCC= 3V, TA= +25°C.) (Note 2)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
Note 1: Signals on NO_, NC_, COM_ exceeding VCCor GND are clamped by internal diodes. IN_ is clamped to GND by an internal
diode. Limit forward-diode current to maximum current rating.
V
CC
, INA, INB to GND...........................................-0.3V to +4.0V
All Other Pins to GND (Note 1)...................-0.3V to (V
CC
+ 0.3V)
Continuous Current (NO_, NC_, COM_)........................ ±300mA
Peak Current (NO_, NC_, COM_)
(pulsed at 1ms, 50% duty cycle)................................±400mA
Peak Current (NO_, NC_, COM_)
(pulsed at 1ms, 10% duty cycle .................................±500mA
Continuous Power Dissipation (T
A
= +70°C)
16-Pin TQFN (derate 15.6mW/°C above +70°C) ............1.25W
16-Pin TSSOP (derate 9.4mW/°C above +70°C) ..........755mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Junction Temperature......................................................+150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER SYMBOL CONDITIONS
POWER SUPPLY
Supply Voltage Range V
CC
1.6 3.6 V
Supply Current I
CC
VCC = 3.6V, V
IN_
= 0 or VCC, NO_ = NC_ =
COM_ = floating
1µA
ANALOG SWITCH
Analog Signal Range NO_, NC_, COM_ 0
0.4
On-Resistance R
ON
VCC = 2.7V,
I
COM_
= 100mA,
V
NO_
or V
NC_
= 0 to V
CC
(Note 3)
On-Resistance Match ∆R
ON
VCC = 2.7V,
I
COM_
= 100mA,
V
NO_
or V
NC_
= 1.5V
(Notes 3, 4)
R
FLAT
VCC = 2.7V;
I
COM_
= 100mA; V
NO_
or
V
NC_
= 0.6V, 1.2V, 1.8V
(Note 5)
Ω
TA = +25°C 20 20
NO_ or NC_ Off-Leakage
Current
I
OFF
VCC = 3.3V;
V
COM_
= 3V, 0.3V or
floating; V
NO_
or V
NC_
=
0.3V, 3V or floating
nA
TA = +25°C 20 20
COM_ On-Leakage
Current
I
ON
VCC = 3.3V;
V
NO_
or V
NC_
= 0.3V, 3V
or fl oati ng ; V
C OM _
= 0.3V ,
3V or fl oati ng
0.015
TA = T
MIN
TA = T
TA = T
TA = T
TA = T
MIN
MIN
MIN
MIN
to T
to T
to T
to T
to T
MAX
MAX
MAX
MAX
MAX
V
CC
0.31
0.45
0.015 0.03
0.03
0.06 0.75
0.080
100 100
100 100

MAX4735
Low-Voltage, 0.31Ω, Quad-SPDT Analog Switch
_______________________________________________________________________________________ 3
Note 2: Devices are 100% tested at TA= +85°C. Limits across the full temperature range are guaranteed by design and correlation.
Note 3: R
ON
and RONmatching specifications are guaranteed by design for MAX4735ETE only.
Note 4: ∆R
ON
= R
ON(MAX)
- R
ON(MIN)
.
Note 5: Flatness is defined as the difference between the maximum and minimum value of on-resistance, as measured over the
specified analog signal ranges.
Note 6: Guaranteed by design, not production tested.
Note 7: Off-isolation = 20log10 [V
COM_
/ (V
NO_
or V
NC_
)], V
COM_
= output, V
NO_
or V
NC_
= input to off switch.
Note 8: Between any two switches.
ELECTRICAL CHARACTERISTICS (continued)
(VCC= 2.7V to 3.6V, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VCC= 3V, TA= +25°C.) (Note 2)
PARAMETER SYMBOL CONDITIONS
DYNAMIC CHARACTERISTICS
Turn-On Time t
Turn-Off Time t
Charge Injection Q V
On-Channel Bandwidth
-3dB
Off-Isolation V
Crosstalk V
Total Harmonic Distortion
Plus Noise
NC_ or NO_ OffCapacitance
Power-Supply Rejection
Ratio
DIGITAL INPUTS (INA,
Input-Logic High V
Input-Logic Low V
Input Leakage Current I
VCC = 2.7V,
ON
or V
NO_
= 50Ω, CL = 35pF,
R
L
NC_
= 1.5V,
V
Figure 1
VCC = 2.7V,
OFF
or V
NO_
= 50Ω, CL = 35pF,
R
L
NC_
= 1.5V,
V
Figure 1
VCC = 2.7V,
t
BBM
or V
NO_
= 50Ω, CL = 35pF,
R
L
NC_
= 1.5V,
V
Figure 2 (Note 6)
BW R
ISO
CT
THD+N
C
NC_(OFF
C
NO_(OFF
C
COM_(ON)
PSRR
IH
IL
IN
= 0V, R
GEN
= 50Ω, Figure 4 20
L
V
= 1V
COM_
C
= 5pF, Figure 4 (Note 7)
L
V
= 1V
COM_
C
= 5pF, Figure 4 (Note 8)
L
f = 20Hz to 20kHz; V
V
= 0.5V
COM_
),
f = 1MHz, V
Figure 5
)
f = 1MHz, VNO_ = VNC_ = V
Figure 5
VAC = 100mV
f = 100kHz
V
= 0 or V
IN_
= 0Ω, CL = 1nF, Figure 3
GEN
, RL = 50Ω, f = 100kHz,
RMS
, RL = 50Ω, f = 100kHz,
RMS
; RL = 32Ω
P-P
_ = VNC_ = V
NO
, V
P-P
COM_
CC
TA = +25°C 40
TA = +25°C 20
TA = +25°C 2 15
, V
NO_
COM_
COM_
,
= 1.5V,
= 1.5V,
NC_
= 1.5V, RL = 50Ω,
ns
200
ns
180
ns
2
pC
-66 dB
-86 dB
%
70 pF
pF
-34 dB
1.4 V
0.5 V
nA

MAX4735
Low-Voltage, 0.31Ω, Quad-SPDT Analog Switch
4 _______________________________________________________________________________________
Timing Circuits/Timing Diagrams
Figure 1. Switching Time
50%
V
CC
0V
LOGIC
INPUT
V
OUT
0.9 x V
OUT
t
BBM
LOGIC
INPUT
R
L
GND
C
L
INCLUDES FIXTURE AND STRAY CAPACITANCE.
NO_
IN_
NC_
V
OUT
V
CC
V
CC
C
L
V
N_
COM_
MAX4735
Figure 2. Break-Before-Make Interval
V
GEN
GND
COM_
C
L
V
OUT
V
CC
V
OUT
IN
OFF
ON
OFF
∆V
OUT
Q = (∆V
OUT
)(CL)
NC_
LOGIC-INPUT WAVEFORMS INVERTED FOR SWITCHES
THAT HAVE THE OPPOSITE LOGIC SENSE.
OFF
ON
OFF
IN
V
IL
TO V
IH
V
CC
R
GEN
IN_
MAX4735
OR NO_
V
CC
Figure 3. Charge Injection
MAX4735
V
N_
LOGIC
INPUT
V
CC
V
CC
NO_
COM_
OR NC_
R
IN_
GND
C
INCLUDES FIXTURE AND STRAY CAPACITANCE.
L
R
= V
N_ (
L
)
ON
V
OUT
RL + R
V
CC
LOGIC
INPUT
V
OUT
L
C
L
SWITCH
OUTPUT
0V
0V
50%
V
OUT
0.9 x V
t
ON
IN DEPENDS ON SWITCH CONFIGURATION;
INPUT POLARITY DETERMINED BY SENSE OF SWITCH.
0UT
50%
t
OFF
0.9 x V
OUT