Download MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H Low-Voltage, Dual SPDT, Audio Clickless Switches with Negative Rail Capability General Description

19-0563; Rev 1; 11/06
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
Features
The MAX4744/MAX4744H/MAX4745/MAX4745H/
MAX4746H dual SPDT (single-pole/double-throw) audio
switches feature negative signal capability that allows
signals as low as VCC - 5.5V to pass through without
distortion. These analog switches have a low on-resistance and low supply current, and operate from a single
+1.8V to +5.5V supply.
The MAX4744/MAX4744H have internal shunt resistors
that automatically discharge the capacitance at the normally open (NO) and normally closed (NC) terminals
when they are not connected. The MAX4746H features
internal shunt resistors on NC_ terminals. This reduces
click-and-pop sounds that occur when switching audio
signals between precharged points. A break-beforemake feature further reduces popping. The MAX4744/
MAX4745 control the switches with two control bits CB1
and CB2. The MAX4744H/MAX4745H/MAX4746H have
one control bit to switch both switches and an enable
input EN to put the switches in a high-impedance mode.
The MAX4744H/MAX4745H/MAX4746H also have an
internal protection network against voltages applied to
COM_ when VCC = 0V.
These devices are available in a space-saving 10-pin
µDFN (2mm x 2mm) package and operate over the
-40°C to +85°C extended temperature range.
Distortion-Free Negative Signal Throughput Down
to VCC - 5.5V
Internal Shunt Resistor Reduces Click/Pop
(MAX4744/MAX4744H)
0.6Ω (typ) Low On-Resistance
0.1Ω (max) Channel-to-Channel Matching
0.55Ω (max) On-Resistance Flatness
+1.8V to +5.5V Single-Supply Voltage
0.01% (typ) Total Harmonic Distortion
-75dB (typ) Crosstalk (100kHz)
-68dB (typ) Off-Isolation (100kHz)
Available in 10-Pin µDFN Package (2mm x 2mm)
Pin Configurations
TOP VIEW
COM1 NC1 VCC NC2 COM2
10
9
8
7
COM1 NC1 VCC
6
10
9
NC2 COM2
8
7
6
4
5
Applications
Speaker Switching
MAX4744H
MAX4745H
MAX4746H
MAX4744
MAX4745
Power Routing
+
+
Cellular Phones
1
MP3 Players
2
3
4
1
5
CB1 NO1 GND NO2 CB2
PDAs and Other Handheld Devices
EN
μDFN
(2mm x 2mm)
Notebook Computers
2
3
NO1 GND NO2 CB0
μDFN
(2mm x 2mm)
Ordering Information/Selector Guide
PINPACKAGE
TOP
MARK
CLICKLESS
COM PROTECTION
PKG CODE
MAX4744ELB+T
10 µDFN-10
+AAF
Yes
No
L1022-1
MAX4744HELB+T
10 µDFN-10
+AAG
Yes
Yes
L1022-1
MAX4745ELB+T
10 µDFN-10
+AAH
No
No
L1022-1
MAX4745HELB+T
10 µDFN-10
+AAI
No
Yes
L1022-1
Yes
L1022-1
PART
MAX4746HELB+T
10 µDFN-10
+AAM
Yes, on NC_
Note: All devices are specified over the -40°C to +85°C operating temperature range.
+Denotes a lead-free package.
________________________________________________________________ Maxim Integrated Products
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.
1
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
General Description
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND.)
VCC, CB_, EN ........................................................-0.3V to +6.0V
NC_, NO_ ...........................................(VCC - 6V) to (VCC + 0.3V)
COM_ (MAX4744/MAX4745).............(VCC - 6V) to (VCC + 0.3V)
COM_ (MAX4744H/MAX4745H/MAX4746H) ..................(Note 1)
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
ESD Protection per Method 3015.7
NO_, NC_, COM_, VCC, GND, CB_, EN...............................±2kV
Continuous Power Dissipation (TA = +70°C)
10-Pin µDFN (derate 5mW/°C above +70°C) ...............403mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Note 1: If VCC > 0.5V, limits are (VCC - 6V) to (VCC + 0.3V). If VCC < 0.5V, limits are (VCC - 6.0V) to +6.0V.
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.
ELECTRICAL CHARACTERISTICS
(VCC = +2.7V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = 3.3V, TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
5.5
V
POWER SUPPLY
Supply-Voltage Range
VCC
Supply Current
ICC
1.8
VCC = 5.5V, VCB_ = 0V or VCC
0.3
1
VCC = 5.5V, VCB_ = 0.5V or 1.4V
8
VCC = 2.7V, VCB_ = 0.5V or 1.4V
4
µA
ANALOG SWITCH
Analog Signal Range
VNC_,
VNO_,
VCOM_
RON
VCC = +2.7V; VNC_ or VNO_
= VCC - 5.5V, -1V, 0V, 1V,
2V, VCC; ICOM_ = 100mA
On-Resistance Match Between
Channels (Notes 4 and 5)
ΔRON
VCC = 2.7V, VNC_ or VNO_ =
0V, ICOM_ = 100mA
On-Resistance Flatness (Note 6)
RFLAT
VCC = +2.7V, VNC_ or VNO_ =
VCC - 5.5V, - 1V, 0V, 1V, 2V,
VCC; ICOM_ = 100mA
On-Resistance (Note 4)
Shunt Switch Resistance
NC_, NO_ Off-Leakage Current
(Note 3)
COM_ On-Leakage Current
(Note 3)
2
RSH
VCC
- 5.5V
(Note 3)
TA = +25°C
VCC
0.6
0.95
TA = TMIN to
TMAX
1.0
TA = +25°C
0.1
TA = TMIN to
TMAX
0.1
TA = +25°C
0.55
TA = TMIN to
TMAX
0.6
MAX4744/MAX4744H/MAX4746H only,
VCC = 2.7V
INO_(OFF),
INC_(OFF)
TA = +25°C
VCC = +2.7V switch open;
VNC_ or VNO_ = -2.5V, +2.5V
TA = TMIN to
(MAX4745/MAX4745H only)
TMAX
(MAX4746H - INO_(OFF) only)
ICOM_(ON)
TA = +25°C
VCC = 2.7V switch closed;
VNC_ or VNO_ = -2.5V, +2.5V; TA = TMIN to
VCOM_ = -2.5V, +2.5V
TMAX
2
5
-15
+15
-50
+50
-15
+15
-100
+100
_______________________________________________________________________________________
V
Ω
Ω
Ω
kΩ
nA
nA
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
ELECTRICAL CHARACTERISTICS (continued)
(VCC = +2.7V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = 3.3V, TA = +25°C.) (Note 2)
PARAMETER
COM_ Leakage Under Protection
Conditions
SYMBOL
IL(PROT)
CONDITIONS
VCC = 0V; VCOM_ = +5.5V;
VNC_ and VNO_ are
unconnected or connected to
GND; VCB_ = 0V
(MAX4744H/MAX4745H/
MAX4746H only)
MIN
TA = +25°C
TYP
MAX
UNITS
30
nA
TA = TMIN to
TMAX
500
DYNAMIC CHARACTERISTICS
Turn-On Time
tON
Turn-Off Time
tOFF
Break-Before-Make Delay Time
Power-Supply Rejection Ratio
Charge Injection
tD
PSRR
Q
For NO_, VNO_ = 1.5V,
VCB_ = 0V to VCC
55
For NC_, VNC_ = 1.5V,
VCB_ = VCC to 0V
560
For NO_, VNO_ = 1.5V,
VCB_ = VCC to 0V
540
For NC_, VNC_ = 1.5V,
VCB_ = 0V to VCC
36
VCC = 2.7V, VNC_ = VNO_ = 1.5V; for NO_,
VCB_ = VCC to 0V; for NC_, VCB_ = 0V to
VCC; RL = 32Ω; CL = 35pF; Figure 3
20
ns
f = 100kHz, VCOM_ = 1VRMS, RL = 50Ω,
CL = 5pF
52
dB
VGEN_ = 0V; RGEN = 0Ω, CL = 1nF, Figure 4
450
pC
-68
dB
VCC = 2.7V,
RL = 32Ω,
CL = 35pF, Figure 2
VCC = 2.7V, RL =
32Ω, CL = 35pF,
Figure 2
ns
ns
Off-Isolation
VISO
CL = 5pF; RL = 50Ω; f = 100kHz;
VCOM_ = 1VRMS; Figure 5 (Note 7)
Crosstalk
VCT
CL = 5pF; RL = 50Ω;
f = 100kHz; VCOM_ = 1VRMS; Figure 5
-75
dB
Total Harmonic Distortion
THD
f = 20Hz to 20kHz, VCOM_ = 0.5VP-P,
RL = 50Ω
0.01
%
NO_, NC_ Off-Capacitance
CNO_(OFF),
f = 1MHz, Figure 6
CNC_(OFF)
90
pF
COM On-Capacitance
CCOM_(ON) f = 1MHz, Figure 6
300
pF
_______________________________________________________________________________________
3
ELECTRICAL CHARACTERISTICS (continued)
(VCC = +2.7V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = 3.3V, TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
0.5
V
+1
µA
DIGITAL INPUTS (CB_, EN)
Input-Logic High
VIH
Input-Logic Low
VIL
Input Leakage Current
1.4
ILEAK
VCB_ or VEN = 0V or VCC
V
-1
Note 2: All parameters are production tested at TA = +25°C and guaranteed by design over the specified temperature range.
Note 3: Signals on COM_, NO_, or NC_ exceeding VCC are clamped by internal diodes. Limit forward-diode current to maximum
current ratings.
Note 4: Guaranteed by design; not production tested.
Note 5: ΔRON = RON(MAX) - RON(MIN).
Note 6: Flatness is defined as the difference between the maximum and minimum value of on-resistance as measured over the
specified analog signal ranges.
Note 7: Off-isolation = 20log10[VCOM_ / VNO_], VCOM_ = output, VNO_ = input to off switch.
Typical Operating Characteristics
(VCC = +3.3V, TA = +25°C, unless otherwise noted.)
ON-RESISTANCE
vs. COM VOLTAGE
VCC = +3V
1.2
VCC = +1.8V
VCC = +5V
0.6
TA = +85°C
0.4
0.3
TA = -40°C
0.2
0
-3
-2
-1
0
1
2
COM VOLTAGE (V)
3
4
5
TA = +25°C
0.4
TA = +85°C
0.3
0.2
TA = -40°C
0.1
0
0.1
-4
VCC = 5V
MAX4744 toc03
0.5
0.5
ON-RESISTANCE (Ω)
1.8
VCC = 3V
TA = +25°C
ON-RESISTANCE (Ω)
2.4
4
0.6
MAX4744 toc01
3.0
ON-RESISTANCE
vs. COM VOLTAGE
MAX4744 toc02
ON-RESISTANCE
vs. COM VOLTAGE
ON-RESISTANCE (Ω)
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
-2.5
-1.4
-0.3
0.8
COM VOLTAGE (V)
1.9
3.0
-0.5
0.6
1.7
2.8
COM VOLTAGE (V)
_______________________________________________________________________________________
3.9
5.0
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
NO_ TURN-ON/NC_ TURN-OFF TIME
vs. TEMPERATURE
NO_ TURN-ON/NC_ TURN-OFF TIME
vs. SUPPLY VOLTAGE
120
TIME (ns)
TIME (ns)
100
600
NC_ TURN-ON TIME
500
80
NO_ TURN-ON TIME
60
NC_ TURN-OFF TIME
400
40
240
MAX4744 toc06
700
MAX4744 toc05
140
MAX4744 toc04
800
NO_ tON
TURN-ON/TURN-OFF TIME (ns)
NC_ TURN-ON/NO_ TURN-OFF TIME
vs. SUPPLY VOLTAGE
200
160
120
NC_ tOFF
80
40
NO_ TURN-OFF TIME
0
20
2.8
3.8
5.5
4.8
1.8
2.3
2.8
SUPPLY VOLTAGE (V)
NO_ TURN-ON/NC_ TURN-OFF TIME
vs. TEMPERATURE
4.3
4.8
LOGIC THRESHOLD (V)
600
NO_ tOFF
5
20
35
50
65
0.8
VCB_ FALLING
0.9
0.6
0
1.8
2.6
3.4
4.2
5.0
0
5.5
1.4
2.0
3.0
CHARGE INJECTION
vs. SUPPLY VOLTAGE
600
TA = +85°C
TA = -40°C
800
700
600
500
400
300
TA = +25°C
0
0.2
1.0
DIGITAL INPUT VOLTAGE (V)
CHARGE INJECTION (pC)
800
0.5
MAX4744 toc11
1000
0.1
80
0.3
COM PROTECTION LEAKAGE CURRENT
vs. SUPPLY VOLTAGE
0
65
1.2
SUPPLY VOLTAGE (V)
200
50
1.5
MAX4744 toc08
1.2
TEMPERATURE (°C)
400
35
SUPPLY CURRENT
vs. LOGIC-INPUT VOLTAGE
VCB_ RISING
80
20
LOGIC THRESHOLD
vs. SUPPLY VOLTAGE
MAX4744 toc10
-25 -10
5
TEMPERATURE (°C)
0
-40
-25 -10
SUPPLY VOLTAGE (V)
0.4
400
-40
5.3
1.6
700
500
3.8
2.0
MAX4744 toc07
NC_ tON
800
COM PROTECTION LEAKAGE CURRENT (nA)
TURN-ON/TURN-OFF TIME (ns)
900
3.3
SUPPLY CURRENT (μA)
1.8
MAX4744 toc09
300
0.3
SUPPLY VOLTAGE (V)
0.4
0.5
200
1.8
2.8
3.8
SUPPLY VOLTAGE (V)
4.8
5.5
_______________________________________________________________________________________
5
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Typical Operating Characteristics
(VCC = +3.3V, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VCC = +3.3V, TA = +25°C, unless otherwise noted.)
LEAKAGE CURRENT
vs. TEMPERATURE
FREQUENCY RESPONSE
MAX4744 toc13
MAX4744 toc12
0
-1
100
ON
ON-LOSS (dB)
LEAKAGE CURRENT (nA)
1000
10
-2
-3
-4
OFF
1.0
-5
0.1
-40
-15
10
35
60
-6
0.001
85
0.01
TEMPERATURE (°C)
OFF-ISOLATION vs. FREQUENCY
1
10
100
CROSSTALK vs. FREQUENCY
-20
CROSSTALK (dB)
-50
-60
MAX4744 toc15
0
MAX4744 toc14
-40
OFF-ISOLATION (dB)
0.1
FREQUENCY (MHz)
-40
-60
-70
-80
-80
0.001
0.01
0.1
1
10
-100
0.001
100
FREQUENCY (MHz)
0.01
0.1
1
10
100
FREQUENCY (MHz)
TOTAL HARMONIC DISTORTION
vs. FREQUENCY
MAX4744 toc17
80
MAX4744 toc16
1
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
60
PSRR (dB)
0.1
THD (%)
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
40
0.01
20
0.001
0.01
0.1
1
FREQUENCY (kHz)
6
10
100
0
0.001
0.01
0.1
FREQUENCY (MHz)
_______________________________________________________________________________________
1
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
PIN
MAX4744/
MAX4745
MAX4744H/
MAX4745H/
MAX4746H
NAME
1
—
CB1
Digital Control Input for Analog Switch 1
EN
Enable Input. Driving EN high causes all switches to be high impedance. Pull EN low for
normal operation.
FUNCTION
—
1
2
2
NO1
Analog Switch 1—Normally Open Terminal
3
3
GND
Ground
4
4
NO2
Analog Switch 2—Normally Open Terminal
5
—
CB2
Digital Control Input for Analog Switch 2
—
5
CB0
Digital Control Input for Analog Switches 1 and 2
6
6
COM2
7
7
NC2
Analog Switch 2—Normally Closed Terminal
8
8
VCC
Positive Supply Voltage from +1.8V to +5.5V
9
9
NC1
10
10
COM1
Analog Switch 2—Common Terminal
Analog Switch 1—Normally Closed Terminal
Analog Switch 1—Common Terminal
Detailed Description
The MAX4744/MAX4744H/MAX4745/MAX4745H/
MAX4746H are low on-resistance, low-voltage, dualSPDT analog switches that operate from a +1.8V to
+5.5V single supply. These devices feature a negative
signal capability that allows signals as low as VCC 5.5V to pass through without distortion.
The MAX4744/MAX4745 feature two digital control bits
to control each switch independently (see Table 1). The
MAX4744H/MAX4745H/MAX4746H have one control bit
to switch both switches and an enable input EN to put
the switches in a high-impedance mode. Driving EN
low takes the switches out of high impedance and CB0
controls both switches (see Table 2).
The MAX4744/MAX4744H have internal shunt resistors
on all NO and NC terminals, and the MAX4746H has
internal shunt resistors on NC terminals to suppress
click-and-pop sounds that can occur when switching
audio signals between precharged points.
Table 1. MAX4744/MAX4745 Truth Table
CONTROL
SWITCH STATE
CB1
CB2
Switch 1
Switch 2
0
0
Connected to NC1
Connected to NC2
0
1
Connected to NC1
Connected to NO2
1
0
Connected to NO1
Connected to NC2
1
1
Connected to NO1
Connected to NO2
Table 2. MAX4744H/MAX4745H/MAX4746H
Truth Table
CONTROL
SWITCH STATE
EN
CB0
Switch 1
Switch 2
0
0
Connected to NC1
Connected to NC2
0
1
Connected to NO1
Connected to NO2
1
X
High Impedance
High Impedance
X = Don’t Care
Applications Information
Digital Control Inputs
The MAX4744/MAX4744H/MAX4745/MAX4745H/
MAX4746H logic inputs accept up to +5.5V, regardless
of supply voltage. For example, with a +3.3V supply,
CB0, CB1, CB2, and EN can be driven low to GND and
high to +5.5V, allowing for mixed logic levels in a system. Driving CB0, CB1, CB2, and EN rail-to-rail minimizes power consumption.
_______________________________________________________________________________________
7
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Pin Description
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
VCC
MAX4744
MAX4744H
NC1
NC1
COM1
SWITCH 1
VCC
SWITCH 1
COM1
HIGH-Z
NO1
NO1
SHUNT
SWITCH
CONTROL
LOGIC
SHUNT
SWITCH
CB1
CB2
NC2
EN
CB0
NC2
SWITCH 2
HIGH-Z
COM2
NO2
GND
MAX4745
NC1
SWITCH 1
COM1
COM1
HIGH-Z
NO1
GND
VCC
MAX4745H
VCC
NC1
SWITCH 1
COM2
SWITCH 2
NO2
NO1
CONTROL
LOGIC
CB1
CB2
EN
CB0
NC2
NC2
SWITCH 2
HIGH-Z
COM2
NO2
NO2
GND
MAX4746H
NO1
COM2
SWITCH 2
GND
VCC
SWITCH 1
COM1
HIGH-Z
NC1
CONTROL
LOGIC
SHUNT
SWITCH
EN
CB0
NC2
HIGH-Z
NO2
COM2
SWITCH 2
GND
Figure 1. Functional Diagram
8
_______________________________________________________________________________________
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
MAX4744/MAX4745/
MAX4744H/MAX4745H/
MAX4746H
VCC
V CC
COM_
NO_
OR NC_
VNC_ OR VNO_
LOGIC
INPUT
50%
0V
VOUT
RL
t OFF
CL
CB_
VOUT
GND
LOGIC
INPUT
SWITCH
OUTPUT
0.8 x V0UT
0V
0.2 x VOUT
t ON
CL INCLUDES FIXTURE AND STRAY CAPACITANCE
RL
VOUT = VN_
RL + RON
(
t r < 5ns
t f < 5ns
VCC
IN DEPENDS ON SWITCH CONFIGURATION;
INPUT POLARITY DETERMINED BY SENSE OF SWITCH.
)
Figure 2. Switching Time
V CC
MAX4744/MAX4745/
MAX4744H/MAX4745H/
MAX4746H
VNC_ = VNO_
LOGIC
INPUT
V CC
50%
0V
NC_
VOUT
COM_
NO_
RL
CB_
LOGIC
INPUT
VCC
CL
GND
0.9 x VOUT
VOUT
tBBM
CL INCLUDES FIXTURE AND STRAY CAPACITANCE
Figure 3. Break-Before-Make Interval
Analog Signal Levels
These devices pass signals from V CC to as low as
VCC - 5.5V, including signals below ground with minimal
distortion and very little change in on-resistance (see the
Typical Operating Characteristics). The switches are bidirectional, so the NO_, NC_, and COM_ terminals can be
used as either inputs or outputs.
COM_ Protection with VCC = 0V
(MAX4744H/MAX4745H/MAX4746H)
This feature prevents any damage to the device due to
improper power-supply sequencing. The protection
applies if a signal is applied on COM_ when VCC is less
than 0.5V. The switch is not protected if V CC goes
above 0.5V due to parasitic capacitive coupling or any
leakage between COM_ and VCC. The signal at COM_
ranges between (VCC - 6.0V) to 6.0V under protection
conditions.
Click-and-Pop Suppression
The MAX4744/MAX4744H have a shunt resistor on all
their NO and NC terminals to automatically discharge
any capacitance when they are not connected to COM.
The shunt resistor reduces audible click-and-pop
sounds that occur when switching between audio
sources. Audible clicks and pops are caused when a
step DC voltage is switched into the speaker. The DC
step transients can be reduced by automatically discharging the side that is not connected to the COM terminal, reducing any residual DC voltage and reducing
clicks and pops.
_______________________________________________________________________________________
9
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Test Circuits/Timing Diagrams
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
Test Circuits/Timing Diagrams
V CC
MAX4744/MAX4745/
MAX4744H/MAX4745H/
MAX4746H
ΔVOUT
VCC
COM_
VOUT
NC_
OR NO_
VOUT
CB_
OFF
CL
GND
ON
OFF
CB_
VIL TO VIH
ON
OFF
CB_
OFF
Q = (ΔV OUT )(C L )
LOGIC INPUT WAVEFORMS INVERTED FOR SWITCHES
THAT HAVE THE OPPOSITE LOGIC SENSE.
Figure 4. Charge Injection
VCC
10nF
NETWORK
ANALYZER
0V OR
VCC
VIN
CB_
VCC
50Ω
50Ω
OFF-ISOLATION = 20log
COM_
OFF-LOSS = 20log
MAX4744
MAX4744H
NC_ MAX4746H
VOUT
NO_
CROSSTALK = 20log
MEAS
REF
VOUT
VIN
VOUT
VIN
VOUT
VIN
GND
50Ω
50Ω
MEASUREMENTS ARE STANDARDIZED AGAINST SHORT AND OPEN AT SOCKET TERMINALS.
OFF-ISOLATION IS MEASURED BETWEEN COM_ AND OFF NO_ OR NC_ TERMINALS.
ON-LOSS IS MEASURED BETWEEN COM_ AND ON NO_ OR NC_ TERMINAL ON EACH SWITCH.
CROSSTALK IS MEASURED FROM ONE CHANNEL TO THE OTHER CHANNEL.
SIGNAL DIRECTION THROUGH SWITCH IS REVERSED; WORST VALUES ARE RECORDED.
Figure 5. Off-Isolation, On-Loss, and Crosstalk
Break-Before-Make Switching
All devices feature break-before-make switching, which
is configured to break (open) the first set of contacts
before engaging (closing) the new contacts. This prevents the momentary connection of the old and new signal paths to the output, reducing click-and-pop sounds.
10
Power-Supply Sequencing and
Overvoltage Protection
Caution: Do not exceed the Absolute Maximum
Ratings since stresses beyond the listed ratings
may cause permanent damage to the device.
Proper power-supply sequencing is recommended for
all CMOS devices. Improper supply sequencing can
force the switch into latch-up, causing it to draw excessive supply current. The only way out of latch-up is to
recycle the power and reapply properly. Connect all
ground pins first, then apply power to VCC, and finally
apply signals to NO_, NC_, and COM_. Follow the
reverse order upon power-down.
______________________________________________________________________________________
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
10nF
MAX4744
COM_
CAPACITANCE
ANALYZER
MAX4744
MAX4744H
MAX4745
MAX4745H
MAX4746H
NC1
MAXIM
DirectDrive™
AUDIO AMP
CB_
COM1
NO1
VIL OR VIH
NC_ OR
NO_
f = 1MHz
GND
CB1
SHUNT
SWITCH
CB2
Figure 6. Channel Off-/On-Capacitance
NC2
Chip Information
AUDIO
COM2
NO2
PROCESS: BiCMOS
______________________________________________________________________________________
11
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Typical Operating Circuit
VCC
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
A
D
XXXX
XXXX
XXXX
b
e
6, 8, 10L UDFN.EPS
MAX4744/MAX4744H/MAX4745/MAX4745H/MAX4746H
Low-Voltage, Dual SPDT, Audio Clickless
Switches with Negative Rail Capability
N
SOLDER
MASK
COVERAGE
E
PIN 1
0.10x45∞
L
L1
1
SAMPLE
MARKING
PIN 1
INDEX AREA
A
A
(N/2 -1) x e)
7
CL
CL
b
L
A
A2
L
e
EVEN TERMINAL
A1
e
ODD TERMINAL
PACKAGE OUTLINE,
6, 8, 10L uDFN, 2x2x0.80 mm
21-0164
-DRAWING NOT TO SCALE-
A
1
2
COMMON DIMENSIONS
MAX.
SYMBOL
MIN.
NOM.
A
0.70
0.75
A1
0.15
0.20
0.25
A2
0.020
0.025
0.035
D
1.95
2.00
E
1.95
2.00
L
0.30
0.40
L1
0.80
-
2.05
2.05
0.50
0.10 REF.
PACKAGE VARIATIONS
PKG. CODE
N
e
b
(N/2 -1) x e
L622-1
6
0.65 BSC
0.30±0.05
1.30 REF.
L822-1
8
0.50 BSC
0.25±0.05
1.50 REF.
L1022-1
10
0.40 BSC
0.20±0.03
1.60 REF.
PACKAGE OUTLINE,
6, 8, 10L uDFN, 2x2x0.80 mm
-DRAWING NOT TO SCALE-
21-0164
A
2
2
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2006 Maxim Integrated Products
CARDENAS
is a registered trademark of Maxim Integrated Products, Inc.