19-4804; Rev 1; 12/08
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
Features
♦ No Power-Supply Sequencing Required
The MAX4708/MAX4709 8-to-1 and dual 4-to-1 fault-protected multiplexers are pin compatible with the industrystandard DG508/DG509. The MAX4708/MAX4709 are
similar to the MAX4508/MAX4509, but these devices do
not have clamp diodes to the supply rails on the switch
outputs. These multiplexers feature fault-protected
inputs, rail-to-rail signal-handling capability, and do not
require power-supply sequencing.
Both devices offer ±40V overvoltage protection with the
supplies off, ±36V protection with the supplies on, and
feature 400Ω (max) on-resistance with 15Ω (max)
matching between channels. The MAX4708/MAX4709
operate with dual supplies of ±4.5V to ±20V or a single
supply of +9V to +36V. All digital inputs have TTL logiccompatible thresholds, ensuring both TTL and CMOS
logic compatibility when using a single +12V supply or
dual ±15V supplies.
For low-voltage applications requiring fault protection,
refer to the MAX4711/MAX4712/MAX4713 data sheet.
♦ All Channels Off with Power Off
♦ Rail-to-Rail Signal Handling
♦ 400Ω (max) On-Resistance
♦ ±40V Fault Protection with Power Off
♦ ±25V Fault Protection with ±15V Supplies
♦ 100ns Fault-Response Time
♦ ±4.5V to ±20V Dual Supplies
♦ +9V to +36V Single Supply
♦ TTL/CMOS-Compatible Logic Inputs
Ordering Information
PART
Applications
TEMP RANGE
PIN-PACKAGE
MAX4708ESE
-40°C to +85°C
16 Narrow SO
16 Wide SO
MAX4708EWE
-40°C to +85°C
Data-Acquisition Systems
MAX4708EPE
-40°C to +85°C
16 Plastic DIP
Industrial and Process Control
MAX4709ESE
-40°C to +85°C
16 Narrow SO
Avionics
MAX4709EWE
-40°C to +85°C
16 Wide SO
MAX4709EPE
-40°C to +85°C
16 Plastic DIP
Signal Routing
Redundancy/Backup Systems
ATE Systems
Hot Swap
Pin Configurations/Functional Diagrams
TOP VIEW
MAX4708
MAX4709
A0 1
16 A1
A0 1
EN 2
15 A2
EN 2
V- 3
LOGIC
14 GND
V- 3
16 A1
15 GND
LOGIC
14 V+
NO1 4
13 V+
NO1A 4
13 NO1B
NO2 5
12 NO5
NO2A 5
12 NO2B
NO3 6
11 NO6
NO3A 6
11 NO3B
NO4 7
10 NO7
NO4A 7
10 NO4B
COM 8
9
NO8
COMA 8
9
SO/DIP
COMB
SO/DIP
Pin Configurations/Functional Diagrams continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
1
MAX4708/MAX4709
General Description
MAX4708/MAX4709
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
ABSOLUTE MAXIMUM RATINGS
(All Voltages Referenced to GND)
V+ ........................................................................-0.3V to +44.0V
V- .........................................................................-44.0V to +0.3V
V+ to V-................................................................-0.3V to +44.0V
COM_, A_, EN (Note 1)........................ (V+ + 0.3V) to (V- - 0.3V)
NO_.........................................................(V+ - 40V) to (V- + 40V)
NO_ to COM_ ..........................................................-36V to +36V
NO_ Voltage with Switch Power On ........................-30V to +30V
NO_ Voltage with Switch Power Off ........................-40V to +40V
Continuous Current into any Terminal. .............................±30mA
Peak Current into any Terminal
(pulsed at 1ms, 10% duty cycle)................................±100mA
Continuous Power Dissipation (TA = +70°C)
16 Narrow SO (derate 8.70mW/°C above +70°C) .......696mW
16 Plastic DIP (derate 10.53mW/°C above +70°C) .....842mW
16 Wide SO (derate 9.52mW/°C above +70°C)...........762mW
Operating Temperature Range
MAX4708E_ E/MAX4709E_E ...........................-40°C to +85°C
Junction Temperature ..................................................... +150°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10s) .................................+300°C
Note 1: COM_, EN, and A_ pins are not fault protected. Signals on COM_, EN, or A_ exceeding V+ or V- are clamped by internal
diodes. Limit forward-diode current to maximum current rating.
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—Dual Supplies
(V+ = +15V, V- = -15V, VA_H = +2.4V, VA_L = +0.8V, VEN = +2.4V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
TA
MIN
E
V-
TYP
MAX
UNITS
V+
V
300
400
ANALOG SWITCH
Fault-Free Analog Signal Range
On-Resistance
On-Resistance Match
Between Channels
NO_ Off-Leakage Current
COM_ Off-Leakage Current
COM_ On-Leakage Current
2
VNO_
(Notes 3, 4)
RON
VCOM_ = ±10V, INO_ = 0.2mA
ΔRON
INO_(OFF)
+25°C
E
500
VCOM_ = ±10V, INO_ = 0.2mA
(Note 5)
+25°C
15
E
20
VCOM_ = ±10V, VNO_ = ±10V
(Note 6)
+25°C
-0.5
+0.5
E
-5
+5
+25°C
-2
+2
VCOM_ = ±10V,
ICOM_(OFF) VNO_ = ±10V
(Note 6)
VCOM_ = ±10V,
ICOM_(ON) VNO_ = ±10V, or
floating (Note 6)
MAX4708
MAX4709
MAX4708
MAX4709
E
-20
+20
+25°C
-1
+1
E
-10
+10
+25°C
-2
+2
E
-25
+25
+25°C
-1
+1
E
-15
+15
_______________________________________________________________________________________
Ω
Ω
nA
nA
nA
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
(V+ = +15V, V- = -15V, VA_H = +2.4V, VA_L = +0.8V, VEN = +2.4V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
TA
MIN
TYP
MAX
UNITS
FAULT PROTECTION
Fault-Protected Analog Signal
Range (Notes 3, 4)
VNO_
COM_ Output Leakage Current,
Supplies On
ICOM_
Power on
+25°C
Power off
VNO_ = ±25, VEN = 0
-25
+25
-40
+40
+25°C
-1
+1
E
-10
+10
NO_ Input Leakage Current,
Supplies On
INO_
VNO_ = ±25V, VCOM_ = ±10V,
VEN = 0
+25°C
-1
+1
E
-10
+10
NO_ Input Leakage Current,
Supplies Off
INO_
VNO_ = ±40V, VCOM = 0,
V+ = 0, V- = 0
+25°C
-1
+1
E
-10
+10
E
V- 0.4
V+
+ 0.4
Fault-Trip Threshold
V
µA
µA
µA
V
±Fault Output Turn-Off Delay
RL = 10kΩ, VNO_ = ±25V
+25°C
100
ns
±Fault Recovery Time
RL = 10kΩ, VNO_ = ±25V
+25°C
1.5
µs
LOGIC INPUT (VEN, VA_)
Logic Threshold High
VIH
Logic Threshold Low
VIL
Input Leakage Current
IIN
E
2.4
V
E
VA_ = 0.8V or 2.4V
E
-1
0.8
V
+1
µA
SWITCH DYNAMIC CHARACTERISTICS
Enable Turn-On Time
tON
VNO_ = ±10V, RL = 1kΩ,
CL = 35pF, Figure 3 (Note 7)
+25°C
Enable Turn-Off Time
tOFF
VNO_ = ±10V, RL = 1kΩ,
CL = 35pF, Figure 3 (Note 7)
+25°C
tTRANS
RL = 1kΩ, CL = 35pF,
Figure 2 (Note 7)
+25°C
Settling Time
tSETT
VNO_ = 5V, RL = 1kΩ,
CL = 35pF
Break-Before-Make Time Delay
tBBM
VNO_ = ±10V, RL = 1kΩ, Figure 4
(Note 4)
Transition Time
Charge Injection
Off-Isolation
Q
VISO
160
E
400
120
E
0.1%
170
350
500
1
E
E
200
250
E
0.01%
275
2.5
10
ns
ns
ns
µs
80
ns
VNO_ = 0, RS = 0, CL = 1.0nF,
Figure 5
+25°C
0
pC
f = 1MHz, VNO_ = 1VRMS, RL = 75Ω,
CL = 15pF, Figure 6 (Note 8)
+25°C
-70
dB
_______________________________________________________________________________________
3
MAX4708/MAX4709
ELECTRICAL CHARACTERISTICS—Dual Supplies (continued)
MAX4708/MAX4709
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
ELECTRICAL CHARACTERISTICS—Dual Supplies (continued)
(V+ = +15V, V- = -15V, VA_H = +2.4V, VA_L = +0.8V, VEN = +2.4V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C.) (Note 2)
PARAMETER
Channel-to-Channel Crosstalk
NO_ Off-Capacitance
SYMBOL
CONDITIONS
TA
VCT
f = 1MHz, VNO_ = 1VRMS, RL = 75Ω,
CL = 15pF, Figure 7 (Note 9)
+25°C
-62
dB
f = 1MHz, Figure 8
+25°C
10
pF
CN_(OFF)
COM_ Off-Capacitance
CCOM_(OFF) f = 1MHz, Figure 8
COM_ On-Capacitance
CCOM_(ON)
f = 1MHz, Figure 8
MAX4708
MAX4709
MAX4708
MAX4709
MIN
TYP
MAX
19
+25°C
pF
14
28
+25°C
UNITS
pF
22
POWER SUPPLY
Power-Supply Range
V+, V-
E
V+ Supply Current
I+
All VA_= 0 or 5V, VNO_ = 0,
VEN = 5V
+25°C
V- Supply Current
I-
All VA_ = 0 or 5V, VNO_ = 0,
VEN = 5V
+25°C
IGND
All VA_= 0 or 5V, VNO_ = 0,
VEN = 5V
+25°C
GND Supply Current
±4.5
±20.0
370
E
525
750
200
E
300
400
200
E
300
500
V
µA
µA
µA
ELECTRICAL CHARACTERISTICS—Single +12V Supply
(V+ = +12V, V- = 0, VA_H = +2.4V, VA_L = +0.8V, VEN = +2.4V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
TA
MIN
E
-0.3
TYP
MAX
UNITS
V+
V
630
950
ANALOG SWITCH
Fault-Free Analog Signal Range
On-Resistance
On-Resistance Match Between
Channels
NO_ Off-Leakage Current
COM_ Off-Leakage Current
4
VNO_
Power on or off (Note 3)
+25°C
RON
VCOM_ = 10V, INO_ = 0.2mA
ΔRON
VCOM_ = 10V, INO_ = 0.2mA
(Note 5)
+25°C
VCOM_ = 10V, 1V, VNO_ = 1V, 10V
(Notes 6, 10)
+25°C
-0.5
E
-10
+10
+25°C
-2
+2
INO_(OFF)
VCOM_ = 10V, 1V,
ICOM_(OFF) VNO_ = 1V, 10V
(Notes 6, 10)
MAX4708
MAX4709
1100
E
10
C, E
35
50
0.01
+0.5
E
-20
+20
+25°C
-1
+1
E
-10
+10
_______________________________________________________________________________________
Ω
Ω
nA
nA
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
(V+ = +12V, V- = 0, VA_H = +2.4V, VA_L = +0.8V, VEN = +2.4V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C.) (Note 2)
PARAMETER
COM_ On-Leakage Current
SYMBOL
CONDITIONS
VCOM_ = 10V, 1V;
ICOM_(ON) VNO_ = 10V, 1V, or
floating (Notes 6, 10)
TA
MAX4708
MAX4709
MIN
TYP
MAX
+25°C
-2
+2
E
-25
+25
+25°C
-1
+1
E
-15
+15
-36
+36
-40
+40
UNITS
nA
FAULT PROTECTION
Fault-Protected Analog Signal
Range (Notes 3, 10)
VNO_
COM_ Output Leakage Current,
Supplies On
ICOM_
Power on
E
Power off
VNO_ = ±36V, V+ = 12V
(Notes 3, 10)
+25°C
-1
+1
E
-10
+10
NO_ Input Leakage Current,
Supplies On
INO_
VNO_ = ±36V, VCOM_ = 0,
V+ = 12V (Notes 3, 10)
+25°C
-1
+1
E
-10
+10
NO_ Input Leakage Current,
Supply Off
INO_
VNO_ = ±40V, V+ = 0, V- = 0
(Notes 3, 10)
+25°C
-1
+1
E
-10
+10
E
2.4
V
µA
µA
µA
LOGIC INPUT (VEN, VA_)
Logic Threshold High
VIH
Logic Threshold Low
VIL
Input Leakage Current
IIN
V
E
VA_ = 0.8V or 2.4V
E
-1
0.03
0.8
V
+1
µA
SWITCH-DYNAMIC CHARACTERISTICS
Enable Turn-On Time
tON
VCOM_ = 10V, RL = 2kΩ,
CL = 35pF, Figure 3 (Note 7)
+25°C
Enable Turn-Off Time
tOFF
VCOM_ = 10V, RL = 2kΩ,
CL = 35pF, Figure 3 (Note 7)
+25°C
RL = 2kΩ, CL = 35pF, Figure 2
(Note 7)
+25°C
Transition Time
tTRANS
0.1%
VNO_ = 5V, RL = 1kΩ,
CL = 35pF
Break-Before-Make Time Delay
tBBM
VCOM_ = 10V, RL = 2kΩ, Figure 4
(Note 4)
+25°C
VNO_ = 0, RS = 0, CL = 1.0 nF,
Figure 5
Charge Injection
Q
NO_ Off-Capacitance
CNO_(OFF)
100
250
350
180
E
tSETT
500
700
E
Settling Time
0.01%
240
E
400
600
1
E
2.5
50
ns
ns
ns
µs
100
ns
+25°C
2
pC
f = 1MHz, VNO_ = 0, Figure 8
+25°C
5
pF
COM_ Off-Capacitance
CCOM_(OFF) f = 1MHz, VNO_ = 0, Figure 8
+25°C
5
pF
COM_ On-Capacitance
CCOM_(ON)
+25°C
28
pF
f = 1MHz, VCOM_ = VNO_ = 0,
Figure 8
_______________________________________________________________________________________
5
MAX4708/MAX4709
ELECTRICAL CHARACTERISTICS—Single +12V Supply (continued)
ELECTRICAL CHARACTERISTICS—Single +12V Supply (continued)
(V+ = +12V, V- = 0, VA_H = +2.4V, VA_L = +0.8V, VEN = +2.4V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
Off-Isolation
VISO
f = 1MHz, VNO_ = 1VRMS, RL =
75Ω, CL = 15pF, Figure 6 (Note 8)
+25°C
-70
dB
Channel-to-Channel Crosstalk
VCT
f = 1MHz, VNO_ = 1VRMS, RL =
75Ω, CL = 15pF, Figure 7 (Note 9)
+25°C
-62
dB
TA
MIN
TYP
MAX
UNITS
POWER SUPPLY
Power-Supply Range
V+
E
I+
9
36
+25°C
All VA_ = VEN = 5V, VNO_ = 0
V+ Supply Current
180
V
300
E
450
All VA_ = 0 or V+, VNO_ = 0, VEN = +25°C
0 or V+
E
112
µA
250
375
Note 2: The algebraic convention is used in this data sheet; the most negative value is shown in the minimum column.
Note 3: NO_ pins are fault protected and COM_ pins are not fault protected. The max input voltage on NO_ pins depends on the
COM_ load configuration. Generally, the max input voltage is ±36V with ±15V supplies and a load referred to ground. For
more detailed information, see the NO_ Input Voltage section.
Note 4: Guaranteed by design and not production tested.
Note 5: ΔRON = RON(MAX) - RON(MIN).
Note 6: Leakage parameters are 100% tested at the maximum rated hot temperature and guaranteed by correlation at TA =
+25°C.
Note 7: Dynamic testing is 100% functionally tested on the ATE system and correlated with the initial design characterization per
Figures 2 and 3.
Note 8: Off-Isolation = 20 ✕ log10 (VCOM_ / VNO_), where VCOM_ = output and VNO_ = input to open switch.
Note 9: Between any two analog inputs.
Note 10: Guaranteed by testing with dual supplies.
Typical Operating Characteristics
(V+ = +15V, V- = -15V, VEN = +2.4V, TA = +25°C, unless otherwise noted.)
V+ = +15V
V- = -15V
400
600
V+ = +20V
V- = 0V
V+ = +15V
V- = -15V
TA = +125°C
500
TA = +70°C
TA = +85°C
400
V+ = +30V
V- = 0V
400
600
RON (Ω)
800
RON (Ω)
V+ = +10V
V- = -10V
V+ = +9V
V- = 0V
V+ = +12V
V- = 0V
V+ = +15V
V- = 0V
MAX4708/09 toc02
V+ = +4.5V
V- = -4.5V
600
1000
MAX4708/09 toc01
1000
800
ON-RESISTANCE vs. VCOM AND TEMPERATURE
(DUAL SUPPLIES)
ON-RESISTANCE vs. VCOM
(SINGLE SUPPLY)
MAX4708/09 toc03
ON-RESISTANCE vs. VCOM
(DUAL SUPPLIES)
RON (Ω)
MAX4708/MAX4709
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
300
200
200
200
0
-15
-10
-5
0
VCOM (V)
5
10
15
20
TA = +25°C
0
6
12
18
VCOM (V)
24
30
36
TA = -55°C
TA = -40°C
0
0
-20
6
100
V+ = +36V
V- = 0V
V+ = +20V
V- = -20V
-15
-10
-5
0
VCOM (V)
_______________________________________________________________________________________
5
10
15
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
ON-RESISTANCE vs. VCOM AND TEMPERATURE
(SINGLE SUPPLY)
600
400
200
TA = +25°C
4
6
MAX4708/09 toc06
MAX4708/09 toc05
INO_OFF
10
5
DUAL SUPPLIES: ±15V
0
SINGLE SUPPLY: +12V
ICOM_OFF
1
-5
-10
0.1
2
0
8
10
12
-40
-15
35
10
60
85
-15
-10
-5
0
5
10
TEMPERATURE (°C)
VCOM (V)
ENABLE TURN-ON/OFF TIMES
vs. SUPPLY VOLTAGE (DUAL SUPPLIES)
ENABLE TURN-ON/OFF TIMES
vs. SUPPLY VOLTAGE (SINGLE SUPPLY)
ENABLE ON/OFF TIMES
vs. TEMPERATURE
tON
200
tOFF
100
0
MAX4708/09 toc08
200
tON
150
300
tOFF
10
15
200
tON
150
100
100
50
50
20
tOFF
0
0
5
0
V+ = +15V
V- = -15V
250
tON/tOFF (ns)
300
V- = GND, VNO_ = +10V
250
tON/tOFF (ns)
400
300
MAX4708/09 toc07
VNO_ = ±10V
18
9
27
-15
-40
36
10
35
60
85
SUPPLY VOLTAGE (V+)
TEMPERATURE (°C)
SUPPLY CURRENT vs. TEMPERATURE
(VA_ = 0)
SUPPLY CURRENT vs. TEMPERATURE
(VA_ = +5V)
LOGIC-LEVEL THRESHOLD VOLTAGE
vs. SUPPLY VOLTAGE
100
0
IGND
-100
-200
I-
-300
I+
300
200
100
0
IGND
-100
-200
-400
-15
10
35
TEMPERATURE (°C)
60
85
DUAL SUPPLIES
2.0
SINGLE SUPPLY
1.5
1.0
-400
-40
2.5
I-
-300
-500
MAX4708/09 toc12
400
3.0
THRESHOLD VOLTAGE (V)
200
V+ = +15V, V- = -15V, VA_ = +5V
500
SUPPLY CURRENT (μA)
I+
300
600
MAX4708/09 toc10
V+ = +15V, V- = -15V, VA_ = 0
400
MAX4708/09 toc11
SUPPLY VOLTAGE (V+, V-)
500
15
MAX4708/09 toc09
VCOM (V)
500
tON/tOFF (ns)
ICOM_ON
TA = -55°C
TA = -40°C
0
SUPPLY CURRENT (μA)
V+ = +15V, V- = -15V,
VCOM = 10V, VNO = ±10V
100
10
Q (pC)
LEAKAGE CURRENT (pA)
800
RON (Ω)
MAX4708/09 toc04
V+ = +12V
TA = +125°C
V- = 0V TA = +70°C
TA = +85°C
CHARGE INJECTION vs. VCOM
LEAKAGE CURRENT vs. TEMPERATURE
1000
±
1000
-40
-15
10
35
TEMPERATURE (°C)
60
85
0
5
10
15
20
25
30
35
40
SUPPLY VOLTAGE (V)
_______________________________________________________________________________________
7
MAX4708/MAX4709
Typical Operating Characteristics (continued)
(V+ = +15V, V- = -15V, VEN = +2.4V, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(V+ = +15V, V- = -15V, VEN = +2.4V, TA = +25°C, unless otherwise noted.)
ICOM (μA)
CROSSTALK
OFF-ISOLATION
-60
-80
50
0
0.01
0.1
1
10
100
1000
0
-50
-100
FOR 0V < VCOM < VSUPPLY,
ICOM = VCOM / RL
-150
-200
0.001
50
-50
FOR |VCOM| < VSUPPLY,
ICOM = VCOM / RL
V+ = +12V
V- = GND
100
-100
-150
-100
150
MAX4708/09 toc15
100
-20
-40
V+ = +15V
V- = -15V
ICOM (μA)
BANDWIDTH
150
200
MAX4708/09 toc14
V+ = +15V
V- = -15V
0
200
MAX4708/09 toc13
20
FAULT CURRENT vs. FAULT VOLTAGE
(SINGLE SUPPLY)
FAULT CURRENT vs. FAULT VOLTAGE
(DUAL SUPPLIES)
FREQUENCY RESPONSE
LOSS (dB)
MAX4708/MAX4709
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
-200
-80
-60
-40
-20
0
20
40
60
-80
-60
-40
-20
VCOM (V)
FREQUENCY (MHz)
INPUT OVERVOLTAGE vs. OUTPUT VOLTAGE
0
40
60
80
FAULT RECOVERY TIME (POSITIVE INPUT)
INPUT OVERVOLTAGE vs. OUTPUT VOLTAGE
MAX4708/09 toc18
MAX4708/09 toc17
MAX4708/09 toc16
20
VCOM (V)
VNO_
INPUT
10V/div
GND
GND
VNO_
INPUT
10V/div
VCOM_
OUTPUT
10V/div
GND
GND
VNO_
INPUT
10V/div
VCOM_
OUTPUT
5V/div
GND
GND
VCOM_
OUTPUT
200mV/div
FAULT RECOVERY TIME (NEGATIVE INPUT)
FAULT RESPONSE TIME (POSITIVE INPUT)
MAX4708/09 toc19
MAX4708/09 toc21
GND
VNO_
INPUT
10V/div
VNO_
INPUT
10V/div
VNO_
INPUT
10V/div
GND
GND
VCOM_
OUTPUT
5V/div
VCOM_
OUTPUT
5V/div
GND
VCOM_
OUTPUT
5V/div
8
FAULT RESPONSE TIME (NEGATIVE INPUT)
MAX4708/09 toc20
GND
1.00μs
1.00μs
200μs
4.00μs
GND
100ns/div
_______________________________________________________________________________________
100ns/div
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
MAX4708 (Single 8-to-1 Mux)
MAX4709 (Dual 4-to-1 Mux)
PIN
NAME
PIN
NAME
1
A0
Address Bit 0
1
A0
Address Bit 0
2
EN
Mux Enable
2
EN
Mux Enable
3
V-
Negative Supply Voltage. Bypass to GND
with a 0.1µF capacitor.
3
V-
Negative Supply Voltage. Bypass to GND
with a 0.1µF capacitor.
4
NO1
Channel Input 1
4
NO1A
Channel Input 1A
5
NO2
Channel Input 2
5
NO2A
Channel Input 2A
6
NO3
Channel Input 3
6
NO3A
Channel Input 3A
7
NO4
Channel Input 4
7
NO4A
Channel Input 4A
8
COM
Analog Output
8
COMA
Mux Output A
9
NO8
Channel Input 8
9
COMB
Mux Output B
10
NO7
Channel Input 7
10
NO4B
Channel Input 4B
11
NO6
Channel Input 6
11
NO3B
Channel Input 3B
12
NO5
Channel Input 5
12
NO2B
Channel Input 2B
13
V+
Positive Supply Voltage. Bypass to GND
with a 0.1µF capacitor.
13
NO1B
14
GND
15
A2
16
A1
FUNCTION
Channel Input 1B
Positive Supply Voltage. Bypass to GND
with a 0.1µF capacitor.
14
V+
Address Bit 2
15
GND
Address Bit 1
16
A1
Ground
FUNCTION
Ground
Address Bit 1
Truth Tables
MAX4708 (Single 8-to-1 Mux)
A2
A1
A0
X
X
0
0
0
MAX4709 (Dual 4-to-1 Mux)
EN
ON SWITCH
A1
A0
X
0
None
X
X
0
None
None
0
1
NO1
0
0
1
NO1A
NO1B
0
1
1
NO2
0
1
1
NO2A
NO2B
0
1
0
1
NO3
1
0
1
NO3A
NO3B
0
1
1
1
NO4
1
1
1
NO4A
NO4B
1
0
0
1
NO5
1
0
1
1
NO6
1
1
0
1
NO7
1
1
1
1
NO8
EN
COMA
COMB
X = Don’t care.
_______________________________________________________________________________________
9
MAX4708/MAX4709
Pin Descriptions
MAX4708/MAX4709
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
Detailed Description
Several unique features differentiate the MAX4708/
MAX4709 from traditional fault-protected multiplexers.
First, instead of the three series FETs utilized in older
designs, the MAX4708/MAX4709 design employs two
parallel FETs for lower on-resistance and improved flatness. Second, older devices limited the range of signal
amplitudes the switch could pass by as much as 3V
below the supply rails. The MAX4708/MAX4709 feature
rail-to-rail signal handling that allows the devices to
transmit signals with amplitudes at or slightly beyond
the supply rails. Finally, in former designs (MAX4508/
MAX4509), when a fault occurred, the devices clamped
and held the output voltage at the appropriate supply
rail until the fault was removed. Instead, the
MAX4708/MAX4709 now disconnect COM_ from NO_
during a fault condition, making COM_ a high-impedance output as long as the fault is present. Operation is
identical for both positive and negative fault polarities.
When the NO_ voltage ranges beyond supply rails
(fault condition), the NO_ input becomes high impedance, regardless of the switch state or load resistance.
If power is removed, and the fault voltage is still present, the NO_ terminals remain high impedance. The
fault voltage can be up to ±40V, with V+ = V- = 0.
The COM_ pins are not fault protected. Limit any voltage sources connected to COM_ to the supply rails.
Figure 1 shows the internal construction of a single normally open (NO) switch, with the analog signal paths
shown in bold. The parallel combination of N-channel
FET N1 and P-channel FET P1 form the analog switch.
During normal operation, these FETs are driven on and
off simultaneously according to the control voltages on
A_. During a fault condition, both FETs turn off.
NO_ Input Voltage
The maximum allowable input voltage for safe operation
depends on whether supplies are on or off, and the load
configuration on COM_. If COM_ is referred to a voltage
other than ground, but within the supplies, VNO_ can
range higher or lower than the supplies, provided the
absolute value of |VNO_ - VCOM_| is less than 40V.
For example, with V+ = V- = 0, if the load is referred to
+10V at COM_, then the NO_ voltage range can be from
+50V to -30V. If the supplies are ±15V and COM_ is referenced to ground through a load, the maximum NO_ voltage is ±36V. If the supplies are off and the COM output is
referenced to ground, the maximum NO_ voltage is ±40V.
Normal Operation
Two comparators continuously compare the voltage on
NO_ with V+ and V- supply voltages. When the signal
10
on NO_ ranges between V+ and V-, the multiplexer
operates normally, with FETs N1 and P1 turning on and
off in response to the control signals on A_ (Figure 1).
When the switch state is on, the parallel combination of
N1 and P1 forms a low-value resistor between NO_ and
COM_ so that signals pass equally well in either direction. When the switch state is off, both NO_ and COM_
are high-impedance inputs.
Fault Conditions
A fault condition occurs when the voltage at any NO_
input exceeds the supply rail. At this point, the output of
one of the two fault comparators goes high, effectively
turning OFF both FETs N1 and P1. With the two FETs in
the OFF position, both the switch input (NO_) and the output (COM_) go into a high-impedance state. They remain
high impedance regardless of the state of the control voltages in A_ and EN, until the fault is removed. The input
voltage must not exceed the absolute maximum rating at
any moment (see the Absolute Maximum Ratings section).
A fault condition on the selected channel drives COM_
to a high-impedance state. However, the fault condition
does not affect the performance of other channels.
Therefore, while the selected channel is in fault condition, selecting another channel or operating under normal condition, drives COM_ out of high impedance.
Transient Fault Condition
When a fast rising or falling transient on NO_ exceeds
V+ or V-, there is a 100ns delay before the fault protection turns on (see the Typical Operating Characteristics , Fault Response Time). COM_ follows NO_
until the fault protection turns on. This delay is due to
the switch on-resistance and circuit capacitance to
ground. When the input transient returns to within the
supply rails, there is a longer output recovery time (see
the Typical Operating Characteristics, Fault Response
Times). These values depend on the COM_ output
resistance and capacitance. Higher COM_ output resistance and capacitance increase the recovery times.
The delays do not depend on the fault amplitude.
COM and A_
The GND, COM_, and A_ pins are not fault protected.
ESD-protection diodes internally connect A_ to both V+
and V-. If a signal on GND, COM_, or A_ exceeds V+ or
V- by more than 300mV, excessive current can flow to
or from the supplies, possibly damaging the device.
Logic-Level Thresholds
The logic-level thresholds are CMOS and TTL compatible
with V+ = +15V and V- = -15V. Logic levels change as V+
increases (see the Typical Operating Characteristics,
Logic-Level Threshold Voltage vs. Supply Voltage.)
______________________________________________________________________________________
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
Ground
V+ and GND power the internal logic and logic-level translators. The logic-level translators convert the logic-level
inputs to V+ and V- to drive the gates of the internal FETs.
In this design, there is no galvanic connection inside the
MAX4708/MAX4709 between the analog signal paths and
GND. ESD-protection diodes connect A_ to V+ and V-.
Chip Information
PROCESS: CMOS
SUBSTRATE INTERNALLY CONNECTED TO V+
Supply Current Reduction
Package Information
Driving the logic signals rail-to-rail from 0 to +15V or
-15V to +15V reduces the current consumption from
370µA (typ) to 200µA (typ) (see the Electrical Characteristics table, Power Supplies).
For the latest package outline information and land patterns, go
to www.maxim-ic.com/packages.
Power Supplies
The MAX4708/MAX4709 operate with bipolar supplies
between ±4.5V and ±20V. The V+ and V- supplies
need not be symmetrical, but V+ - V- cannot exceed
the 44V absolute maximum rating.
PACKAGE TYPE
PACKAGE CODE
DOCUMENT NO.
16 Narrow SO
—
21-0041
16 Wide SO
—
21-0042
16 Plastic DIP
—
21-0043
The MAX4708/MAX4709 operate from single supplies
between +9V and +36V when V- is connected to GND.
Pin Configurations/Functional Diagrams (continued)
NORMALLY OPEN SWITCH CONSTRUCTION
V+
HIGH
FAULT
P1
NO_
COM_
N1
LOW
FAULT
ON
A_
MAX4708
MAX4709
GND
VESD DIODES
Figure 1. Functional Diagram
______________________________________________________________________________________
11
MAX4708/MAX4709
Applications Information
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
MAX4708/MAX4709
Test Circuits/Timing Diagrams
V+
NO1
A2
A1
+10V
NO2–NO7
A0
MAX4708
+2.4V
NO8
EN
-10V
COM
GND
VOUT
V-
CL
50Ω
LOGIC
INPUT
VA_
RL
tR < 20ns
tF < 20ns
+3V
50%
0V
VNO1
SWITCH
OUTPUT
VOUT
V+
NO1B
A1
+10V
90%
0V
90%
A0
VNO8
NO1A–NO4A
+2.4V
NO4B
MAX4709
EN
-10V
GND
tTRANS
tTRANS
COMB
V-
ON
VOUT
CL
50Ω
RL
Figure 2. Address Transition Time
VEN
V+
EN
NO1
+10V
NO2–NO8
A0
A1
MAX4708
A2
COM
GND
50Ω
VOUT
V-
CL
RL
LOGIC
INPUT
VEN
+3V
50%
tR < 20ns
tF < 20ns
0V
tOFF(EN)
tON(EN)
0V
VEN
V+
EN
50Ω
+10V
NO1A–NO4A
NO2B–NO4B,
COMA
A0
A1
NO1B
90%
SWITCH
OUTPUT
VOUT
10%
MAX4709
GND
COMB
V-
VOUT
RL
CL
Figure 3. Enable Switching Time
12
______________________________________________________________________________________
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
VEN
+2.4V
V+
EN
NO1–NO8
A0
LOGIC
INPUT
VA
+10V
MAX4708
50%
0V
+5V
A1
VA
tR < 20ns
tF < 20ns
+3V
80%
A2
COM
GND
SWITCH
OUTPUT
VOUT
VOUT
V-
35pF
tOPEN
0V
1kΩ
50Ω
Figure 4. Break-Before-Make Interval
RS
NO
VEN
VS
A0
CHANNEL
SELECT
V+
LOGIC
INPUT
VEN
EN
MAX4708
COM
+3V
OFF
ON
OFF
0V
VOUT
A1
A2
ΔVOUT
1nF
GND
VOUT
V-
ΔVOUT IS THE MEASURED VOLTAGE DUE TO CHARGE TRANSFER
ERROR VCTE WHEN THE CHANNEL TURNS OFF.
VCTE = ΔVOUT X CL
Figure 5. Charge Injection
10nF
NO1
VIN
RS = 50Ω
10nF
V+
NO1
NO8
R
1kΩ
MAX4708
COM
A0
VOUT
GND EN
V-
RL
75Ω
MAX4708
COM
A1
A2
10nF
GND EN
V-
VOUT
RL
75Ω
10nF
OFF-ISOLATION = 20log
Figure 6. Off-Isolation
NO8
A0
RG = 50Ω
A1
A2
VIN
V+
NO2
VOUT
VIN
CROSSTALK = 20log
VOUT
VIN
Figure 7. Crosstalk
______________________________________________________________________________________
13
MAX4708/MAX4709
Test Circuits/Timing Diagrams (continued)
MAX4708/MAX4709
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
Test Circuits/Timing Diagrams (continued)
CHANNEL
SELECT
VNO_
V+
A2
A1
VCOM_
A0
V-
EN
+15V
1MHz
CAPACITANCE
ANALYZER
NO8
MAX4708
GND
+25V
NO1
-15V
COM
f = 1MHz
-25V
Figure 9. Transient Behavior of Fault Condition
Figure 8. NO_, COM_ Capacitance
Functional Diagrams/Truth Tables
MAX4708
V+
V-
GND
MAX4708
NO1
A2
A1
A0
EN
ON SWITCH
NO2
NO3
X
X
X
0
NONE
NO4
0
0
0
1
1
0
0
1
1
2
0
1
0
1
3
0
1
1
1
4
1
0
0
1
5
1
0
1
1
6
1
1
0
1
7
1
1
1
1
8
COM
NO5
NO6
NO7
NO8
DECODERS/DRIVERS
A0
MAX4709
A1
A2
V+
V-
EN
LOGIC 0 VAL ≤ +0.8V, LOGIC 1 VAH ≥ +2.4V
GND
NO1A
NO2A
NO3A
MAX4709
COMA
NO4A
NO1B
COMB
NO2B
NO3B
NO4B
A1
A0
EN
ON SWITCH
X
X
0
NONE
0
0
1
1
0
1
1
2
1
0
1
3
1
1
1
4
DECODERS/DRIVERS
LOGIC 0 VAL ≤ +0.8V, LOGIC 1 VAH ≥ +2.4V
A0
14
A1
EN
______________________________________________________________________________________
Fault-Protected, Single 8-to-1/
Dual 4-to-1 Multiplexers
REVISION
NUMBER
REVISION
DATE
0
9/02
Initial release
1
12/08
Added chip process and packaging information; changed fault conditions
information
DESCRIPTION
PAGES
CHANGED
⎯
10, 11
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15
© 2008 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
MAX4708/MAX4709
Revision History
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