General Description
The MAX4645/MAX4646 single-pole, single-throw (SPST)
analog switches feature a 2.5Ωtypical on-resistance
(RON) from a +5V supply. RON is flat (0.4Ωmax) over the
specified signal range. Each switch can handle Rail-to-
Rail®analog signals. Off-leakage current is 0.25nA max at
+25°C. These analog switches are ideal in low-distortion
applications and are the preferred solution over mechani-
cal relays in automated test equipment or applications
where current switching is required. They have low power
requirements, require less board space, and are more
reliable than mechanical relays.
These switches operate from a +1.8V to +5V single sup-
ply, making them ideal for use in battery-powered applica-
tions. The MAX4645/MAX4646 have fast switching speeds
of 12ns turn-on time (tON) and 8ns turn-off time (tOFF).
The MAX4645 is a normally open (NO) switch, and the
MAX4646 is a normally closed (NC) switch. Both are
available in 5-pin SOT23, 6-pin SOT23, and 8-pin µMAX
packages.
________________________Applications
Battery-Powered Systems
Audio and Video Signal Routing
Low-Voltage Data-Acquisition Systems
Sample-and-Hold Circuits
Communications Circuits
Relay Replacement
____________________________Features
♦+1.8V to +5V Single-Supply Operation
♦Guaranteed RON
2.5Ωmax (5V supply)
3.5Ωmax (3V supply)
♦1.8V Operation
RON 30Ωtyp Over Temperature
tON 40ns typ, tOFF 20ns typ
♦Low RON Flatness: 0.4Ωmax
♦Guaranteed Low Leakage Currents
±0.25nA at +25°C
♦Rail-to-Rail Output Capability
♦TTL/CMOS-Logic Compatible
♦-75dB Off-Isolation at 1MHz
♦Low Distortion: 0.014% typ
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
________________________________________________________________ Maxim Integrated Products 1
19-1653; Rev 2; 2/04
Ordering Information
Pin Configurations/Functional Diagrams/Truth Tables
µMAX/SO/DIP
PIN 5 5
XYZA
4
123
NOTE: SOT23-5 PACKAGE
HAS LETTERING NEAREST PIN 5.
TOP VIEW
IN
GND
15V+
COM
MAX4645
2
34
SOT23-5
INPUT
0
1
SWITCH STATE
MAX4645
OFF
ON
MAX4646
ON
OFF
SWITCHES SHOWN FOR LOGIC 0 INPUT.
NO
µMAX/SO/DIP
IN
GND
15V+
COM
MAX4646
2
34
SOT23-5
NC
MAX4645EUT-T -40°C to +85°C
PART TEMP RANGE
MAX4645EUK-T -40°C to +85°C
MAX4646EUK-T -40°C to +85°C
MAX4646EUT-T -40°C to +85°C
MAX4646EUA -40°C to +85°C
MAX4645EUA -40°C to +85°C
8 µMAX
6 SOT23-6
5 SOT23-5
8 µMAX
6 SOT23-6
5 SOT23-5
PIN-
PACKAGE
—
AAHM
ADOC
—
AAHL
ADOB
TOP
MARK
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
Pin Configurations/Functional Diagrams/
Truth Tables continued at end of data sheet.
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.
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
2_______________________________________________________________________________________
V+, VIN to GND...........................................................-0.3 to +6V
COM, NO, NC to GND (Note 1)....................-0.3V to (V+ + 0.3V)
Continuous Current (any terminal)....................................±50mA
Peak Current COM, NO, NC
(pulsed at 1ms 10% duty cycle)................................±100mA
Continuous Power Dissipation (TA= +70°C)
5-Pin SOT23 (derate 7.1mW/°C above+70°C)............571mW
6-Pin SOT23 (derate 8.7mW/°C above +70°C)...........696mW
8-Pin µMAX (derate 4.1mW/°C above+70°C) .............330mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
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.
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS—Single +5V Supply
(V+ = 4.5V to 5.5V, VIH = 2.4V, VIL = 0.8V, TA= TMIN to TMAX, unless otherwise specified.) (Notes 2, 3)
Note 1: Signals on NO, NC, or COM, exceeding V+ or GND are clamped by internal diodes. Limit forward current to maximum current
rating.
TA= +25°C
Turn-Off Time (Note 5) tOFF 810
ns
TA= +25°C
VIN_ = 0.8V or 2.4V
-0.35 0.35
TA= TMIN to TMAX
TA= +25°C
0.6
TA= TMIN to TMAX
TA= +25°C
3
TA= +25°C
ICOM = 10mA,
VNO or VNC = 0 to V+,
V+ = 4.5V
-0.35 0.35
PARAMETER SYMBOL MIN TYP MAX UNITSCONDITIONS
Turn-On Time (Note 5) tON 12 15 ns
VNO, VNC = 3V, RL= 300Ω,
CL= 35pF, Figure 2
VNO, VNC = 3V, RL= 300Ω,
CL= 35pF, Figure 2
Logic Input Current IIN -0.1 0.005 0.1 µA
12
Input Logic Low VIL 0.8 V
TA= TMIN to TMAX
Input Logic High VIH 2.4 V
18
TA= TMIN to TMAX
COM On-Leakage Current
(Notes 5, 6) ICOM(ON)
-0.25 0.01 0.25 nA
COM Off-Leakage Current
(Notes 5, 6) ICOM(OFF)
-0.25 0.01 0.25 nA
TA= TMIN to TMAX
TA= +25°C
-0.35 0.35
TA= TMIN to TMAX
TA= +25°C
Off-Leakage Current
(NO or NC) (Notes 5, 6)
INO(OFF),
INC(OFF)
-0.25 0.01 0.25 nA
VCOM = 1V, 4.5V;
VNO or VNC = 4.5V, 1V;
V+ = 5.5V
On-Resistance Flatness
(Note 4) RFLAT(ON)
0.1 0.4
Ω
ICOM = 10mA,
VNO or VNC = 0 to V+,
V+ = 4.5V
COM to NO or NC
On-Resistance RON
1.5 2.5
Ω
TA= TMIN to TMAX
Input Voltage Range VCOM,
VNO, VNC 0V+
V
VCOM = 1V, 4.5V;
VNO or VNC = 4.5V, 1V;
V+ = 5.5V
ANALOG SWITCH
SWITCH DYNAMIC CHARACTERISTICS
V+ = 5.5V; VCOM = 4.5V,
1V; VNO or VNC = 4.5V,
1V, or floating
LOGIC INPUT
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS—Single +3V Supply
(V+ = 2.7V to 3.3V, VIH = 2.0V, VIL = 0.4V, TA= TMIN to TMAX, unless otherwise specified.) (Notes 2, 3)
ELECTRICAL CHARACTERISTICS—Single +5V Supply (continued)
(V+ = 4.5V to 5.5V, VIH = 2.4V, VIL = 0.8V, TA= TMIN to TMAX, unless otherwise specified.) (Notes 2, 3)
V
0V+
VCOM,
VNO, VNC
Input Voltage Range
TA= TMIN to TMAX
Ω
2.5 3.5
RON
COM to NO or NC
On-Resistance
ICOM = 10mA,
VNO or VNC = 0 to V+,
V+ = 2.7V
Ω
0.5 0.9
RFLAT(ON)
On-Resistance Flatness
(Note 4)
VCOM = 1V, 3V;
VNO or VNC = 3V, 1V;
V+ = 3.3V
nA
-0.25 0.01 0.25
INO(OFF),
INC(OFF)
Off-Leakage Current
(NO or NC) (Notes 5, 6)
TA= +25°C
TA= TMIN to TMAX -0.35 0.35
TA= +25°C
TA= TMIN to TMAX
VCOM = 1V, 3V;
VNO or VNC = 3V, 1V;
V+ = 3.3V
nA
-0.25 0.01 0.25
ICOM(OFF)
COM Off-Leakage Current
(Notes 5, 6)
V+ = 3.3V; VCOM = 1V, 3V;
VNO or VNC = 1V,
3V or floating
nA
-0.25 0.01 0.25
ICOM(ON)
COM On-Leakage Current
(Notes 5, 6)
CONDITIONS UNITSMIN TYP MAXSYMBOLPARAMETER
-0.35 0.35
ICOM = 10mA,
VNO or VNC = 0 to V+,
V+ = 2.7V
TA= +25°C
4.5
TA= +25°C
TA= TMIN to TMAX 1
TA= +25°C
TA= TMIN to TMAX -0.35 0.35
ANALOG SWITCH
-75 dB
VNO = VNC = 1VRMS,
RL= 50Ω, CL= 5pF,
f = 1MHz, Figure 4
TA= +25°C
PARAMETER SYMBOL MIN TYP MAX
1.0
UNITS
Positive Supply Current I+ 0.0001
V+ = 5.5V, VIN = 0 or V+,
all channels on or off
Total Harmonic Distortion THD 0.014 %
RL= 600Ω, 5VP-P,
f = 20Hz to 20kHz
CONDITIONS
TA= TMIN to TMAX
TA= +25°C
TA= +25°C
Off-Isolation (Note 7) VISO
-55 dB
VNO = VNC = 1VRMS,
RL= 50Ω, CL= 5pF,
f = 10MHz, Figure 4
COM On-Capacitance CCOM 38 pF
VCOM = VNO, VNC = GND
f = 1MHz, Figure 5
COM Off-Capacitance CCOM 17 pF
VCOM = GND, f = 1MHz,
Figure 5
NO or NC Capacitance COFF 17 pF
VNO , VNC = GND,
f = 1MHz, Figure 5
Charge Injection Q5pC
VGEN = 2V, CL= 1.0nF,
RGEN = 0, Figure 3
TA= +25°C
TA= +25°C
TA= +25°C
TA= +25°C
TA= +25°C
µA
POWER SUPPLY
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
4_______________________________________________________________________________________
Note 2: The algebraic convention, where the most negative value is a minimum and the most positive value is a maximum, is used
in this data sheet.
Note 3: SOT packages are 100% production tested at +25°C. Limits at the maximum rated temperature are guaranteed by
correlation.
Note 4: Flatness is defined as the difference between the maximum and the minimum value of on-resistance as measured over the
specified analog signal ranges.
Note 5: Guaranteed by design.
Note 6: Leakage parameters are 100% tested at +85°C and guaranteed by correlation at +25°C.
Note 7: Off-Isolation = 20log10(VCOM / VNO), VCOM = output, VNO = input to off switch.
ELECTRICAL CHARACTERISTICS—Single +3V Supply (continued)
(V+ = 2.7V to 3.3V, VIH = 2.0V, VIL = 0.4V, TA= TMIN to TMAX, unless otherwise specified.) (Notes 2, 3)
-75
TA= +25°C
Turn-Off Time (Note 5) tOFF
810
ns
TA= +25°C
VIN_ = 0.4V or 2.0V
VNO = VNC = 1VRMS,
RL= 50Ω, CL= 5pF,
f = 1MHz, Figure 4
TA= +25°C
PARAMETER SYMBOL MIN TYP MAX
1.0
UNITS
Positive Supply Current I+ 0.0001 µA
V+ = 3.3V, VIN = 0 or V+,
all channels on or off
CONDITIONS
TA= TMIN to TMAX
TA= +25°C
Off-Isolation (Note 7) VISO
-55
dB
VNO = VNC = 1VRMS,
RL= 50Ω, CL= 5pF,
f = 10MHz, Figure 4
COM On-Capacitance CCOM 38 pF
VCOM = VNO, VNC = GND,
f = 1MHz, Figure 5
COM Off-Capacitance CCOM 17 pF
VCOM = GND, f = 1MHz,
Figure 5
NO or NC Capacitance COFF 17 pF
VNO, VNC = GND,
f = 1MHz, Figure 5
Charge Injection Q4pC
VGEN = 1.5V, CL= 1.0nF,
RGEN = 0, Figure 3
TA= +25°C
TA= +25°C
TA= +25°C
TA= +25°C
TA= +25°C
Turn-On Time (Note 5) tON
12 15 ns
VNO, VNC = 2.0V,
RL= 300Ω,C
L= 35pF,
Figure 2
VNO, VNC = 2.0V,
RL= 300Ω,C
L= 35pF,
Figure 2
Logic Input Current IIN -1 0.005 1 µA
13
Input Logic Low VIL 0.4 V
TA= TMIN to TMAX
Input Logic High VIH 2.0 V
20
TA= TMIN to TMAX
LOGIC INPUT
SWITCH DYNAMIC CHARACTERISTICS
POWER SUPPLY
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
_______________________________________________________________________________________ 5
-10
0
10
20
30
40
50
60
70
012345
SUPPLY CURRENT vs. SUPPLY VOLTAGE
AND TEMPERATURE
MAX4645/6-04
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (nA)
TA = +85°C
TA = +25°C
TA = -40°C
0
4
2
8
6
10
12
-40 0 20-20 40 60 10080
TURN-ON/TURN-OFF TIME
vs. TEMPERATURE
MAX4645/6-05
TEMPERATURE (°C)
tON/tOFF (ns)
tON
tOFF
VCOM = 3V
V+ = 5V
0
2
1
4
3
5
6
7
8
1.0 2.0 2.51.5 3.0 3.5 4.0 4.5 5.0
TURN-ON/TURN-OFF TIME
vs. VCOM
MAX4645/6-06
VCOM (V)
tON/tOFF (ns)
tON
tOFF
V+ = 5V
0
4
2
8
6
10
12
021345
ON-RESISTANCE vs. VCOM
AND SUPPLY VOLTAGE
MAX4645/6-01
VCOM (V)
RON (Ω)
V+ = 1.8V
V+ = 2.5V
V+ = 3V
V+ = 5V
0
0.5
1.5
1.0
2.0
2.5
021345
ON-RESISTANCE vs. VCOM
AND TEMPERATURE
MAX4645/6-02
VCOM (V)
RON (Ω)
TA = +85°C
TA = +25°C
TA = -40°C
V+ = 4.5V
1
-40 -20 0 20 40 60 80
0.01
0.1
ON/OFF-LEAKAGE CURRENT
vs. TEMPERATURE
MAX4645/6-03
TEMPERATURE (°C)
ON/OFF-LEAKAGE (nA)
ON-LEAKAGE
OFF-LEAKAGE
V+ = 5.5V
__________________________________________Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
0.016
0.014
0.012
0.010
0.008
0.006
0.004
0.002
00.01 1 100.1 100
MAX4645/6-08
FREQUENCY (kHz)
THD (%)
TOTAL HARMONIC DISTORTION
vs. FREQUENCY
INPUT IMPEDANCE = 600Ω
f = 20Hz TO 50kHz
0
-100
0.1 1 10 100 1000
FREQUENCY RESPONSE
-80
MAX4645/6-09
FREQUENCY (MHz)
RESPONSE (dB)
-60
-40
-20
-30
-50
-70
-90
-10
V+ = 5V
50Ω IN AND OUT
ON-LOSS
OFF-LOSS
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
6_______________________________________________________________________________________
Detailed Description
The MAX4645/MAX4646 are low 2.5Ωmax on-resis-
tance (at V+ = 5V), low-voltage analog switches that
operate from a +1.8V to +5.5V single supply. CMOS
switch construction allows processing analog signals
that are within the supply voltage range (GND to V+).
Applications Information
Proper power-supply sequencing is recommended for
all CMOS devices. Do not exceed the absolute maxi-
mum ratings because stresses beyond the listed rat-
ings can cause permanent damage to the devices.
Always sequence V+ on first, followed by the logic
inputs, NO, or COM. If power-supply sequencing is not
possible, add two small signal diodes (D1, D2) in series
with the supply pins for overvoltage protection (Figure
1). Adding these diodes reduces the analog signal by
one diode drop below V+ and one diode drop above
GND, but does not affect the low switch resistance and
low leakage characteristics of the device. Device oper-
ation is unchanged, and the difference between V+ and
GND should not exceed 6V.
Although it is not required, power-supply bypassing
improves noise margin and prevents switching noise
from propagating from the V+ supply to other compo-
nents. A 0.1µF capacitor, connected from V+ to GND,
is adequate for most applications.
Pin Description
POSITIVE SUPPLY
COM NO
GND
Vg
V+ MAX4645
MAX4646
D2
D1
Figure 1. Overvoltage Protection Using Two External Blocking
Diodes
V+
COM
NO
NC
GND
IN
N.C.5
6
SOT23-6
2
—
3
4
1
4
µMAX
1
—
8
7
6
2, 3, 5—
5
SOT23-5
—
2
3
4
1
2, 3, 5
4
µMAX
8
—
7
6
1
—
5 6
SOT23-5 SOT23-6
Positive Supply Voltage
1Analog Switch Common Terminal
2 — Analog Switch Normally Open Terminal
— 2 Analog Switch Normally Closed Terminal
3 3 Ground
4 4 Logic Control Input
1
5No Connection. Not internally connected.
MAX4646MAX4645 NAME
PIN
FUNCTION
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
_______________________________________________________________________________________ 7
VGEN GND
NO
CL
VOUT
V+ VOUT
∆VOUT
Q = (∆VOUT)(CL)
COM
OFF ON OFF
IN
VIN
V+
RGEN
IN
MAX4645
MAX4646
Figure 3. Charge Injection
tr < 5ns
tf < 5ns
50%
0
LOGIC
INPUT
RL
300Ω
NO
GND
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
VOUT = VCOM ( RL )
RL + RON
SWITCH
INPUT
IN
V+
tOFF
0
COM
SWITCH
OUTPUT
0.9 × V0UT 0.9 × VOUT
tON
VOUT
SWITCH
OUTPUT
LOGIC
INPUT
LOGIC INPUT WAVEFORMS INVERTED FOR SWITCHES
THAT HAVE THE OPPOSITE LOGIC SENSE.
V+
CL
35pF
V+
VOUT
MAX4645
MAX4646
VCOM
Figure 2. Switching Time
Test Circuits/Timing Diagrams
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
8_______________________________________________________________________________________
_________________________________Test Circuits/Timing Diagrams (continued)
IN
VIL OR
VIH
SIGNAL
GENERATOR 0dBm
V+
10nF
ANALYZER NO
RL
GND
COM V+
MAX4645
MAX4646
Figure 4. Off-Isolation/On-Channel Bandwidth
CAPACITANCE
METER NC OR
NO
COM
GND
IN VIL OR
VIH
10nF V+
f = 1MHz
V+
MAX4645
MAX4646
Figure 5. Channel Off/On-Capacitance
Chip Information
TRANSISTOR COUNT: 50
TOP VIEW
NO
IN
GND
16V+
COM
MAX4645
SOT23-6
2 5
34
NC
IN
GND
16V+
N.C.
N.C.
COM
MAX4646
SOT23-6
25
34
N.C. = NOT INTERNALLY CONNECTED
SWITCHES SHOWN FOR LOGIC 0 INPUT.
IN
N.C.
N.C.
V+
1
2
8
7
NO
GND
N.C.
COM
MAX4645
3
4
6
5
IN
N.C.
N.C.
V+
1
2
8
7
NC
GND
N.C.
COM
MAX4646
µMAX
3
4
6
5
µMAX
INPUT
0
1
SWITCH STATE
MAX4645
OFF
ON
MAX4646
ON
OFF
PIN 6 6
XYZA
4
123
NOTE: SOT23-6
PACKAGE
HAS LETTERING
NEAREST PIN 6.
5
Pin Configurations/Functional Diagrams/Truth Tables (continued)
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
_______________________________________________________________________________________ 9
SOT-23 5L .EPS
E
1
1
21-0057
PACKAGE OUTLINE, SOT-23, 5L
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.)
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
10 ______________________________________________________________________________________
6LSOT.EPS
F1
1
21-0058
PACKAGE OUTLINE, SOT-23, 6L
g()
Package Information (continued)
(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.)
MAX4645/MAX4646
Fast, Low-Voltage, 2.5Ω, SPST,
CMOS Analog Switches
8LUMAXD.EPS
PACKAGE OUTLINE, 8L uMAX/uSOP
1
1
21-0036 J
REV.DOCUMENT CONTROL NO.APPROVAL
PROPRIETARY INFORMATION
TITLE:
MAX
0.043
0.006
0.014
0.120
0.120
0.198
0.026
0.007
0.037
0.0207 BSC
0.0256 BSC
A2 A1
c
eb
A
L
FRONT VIEW SIDE VIEW
E H
0.6±0.1
0.6±0.1
ÿ 0.50±0.1
1
TOP VIEW
D
8
A2 0.030
BOTTOM VIEW
16∞
S
b
L
H
E
D
e
c
0∞
0.010
0.116
0.116
0.188
0.016
0.005
8
4X S
INCHES
-
A1
A
MIN
0.002
0.950.75
0.5250 BSC
0.25 0.36
2.95 3.05
2.95 3.05
4.78
0.41
0.65 BSC
5.03
0.66
6∞0∞
0.13 0.18
MAX
MIN
MILLIMETERS
-1.10
0.05 0.15
α
α
DIM
Note: The MAX4645/MAX4646 do not have an exposed paddle.
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.
11 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
©2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Package Information (continued)
(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.)