General Description
The MAX4508/MAX4509 are 8-to-1 and dual 4-to-1 fault-
protected multiplexers that are pin compatible with the
industry-standard DG508/DG509. The MAX4508/
MAX4509 operate with dual supplies of ±4.5V to ±20V or
a single supply of +9V to +36V. These multiplexers fea-
ture fault-protected inputs, rail-to-rail signal handling
capability, and overvoltage clamping at 150mV beyond
the rails.
Both parts offer ±40V overvoltage protection with sup-
plies off and ±25V protection with supplies on. On-
resistance is 400Ωmax and is matched between
channels to 15Ωmax. All digital inputs have TTL logic
thresholds, ensuring both TTL and CMOS logic com-
patibility when using a single +12V supply or dual ±15V
supplies.
Applications
Data-Acquisition Systems
Industrial and Process Control
Avionics
Signal Routing
Redundant/Backup Systems
Features
♦±40V Fault Protection with Power Off
±25V Fault Protection with ±15V Supplies
♦Rail-to-Rail Signal Handling
♦No Power-Supply Sequencing Required
♦All Channels Off with Power Off
♦Output Clamped to Appropriate Supply Voltage
During Fault Condition
♦1kΩOutput Clamp Resistance During
Overvoltage
♦400ΩΩmax On-Resistance
♦20ns Fault-Response Time
♦±4.5V to ±20V Dual Supplies
+9V to +36V Single Supply
♦TTL/CMOS-Compatible Logic Inputs
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
________________________________________________________________ Maxim Integrated Products 1
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
A1
A2
GND
V+
NO1
V-
EN
A0
TOP VIEW
MAX4508
NO5
NO6
NO7
NO8
COM
NO4
NO3
NO2
SO/DIP
LOGIC
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
A1
GND
V+
NO1B
NO1A
V-
EN
A0
MAX4509
NO2B
NO3B
NO4B
COMB
COMA
NO4A
NO3A
NO2A
SO/DIP
LOGIC
Pin Configurations/Functional Diagrams
19-1414; Rev 5; 10/07
Ordering Information continued at end of data sheet.
*Contact factory for dice specifications.
**Contact factory for availability.
+Denotes a lead-free package.
Functional Diagrams/Truth Tables appear at end of
data sheet.
Ordering Information
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.
PART TEMP
RANGE
PIN-
PACKAGE
PKG
CODE
MAX4508CSE+
0°C to +70°C 16 Narrow SO
S16-8
MAX4508CPE+
0°C to +70°C 16 Plastic DIP
P16-4
MAX4508C/D
0°C to +70°C
Dice* —
MAX4508ESE+
-40°C to +85°C 16 Narrow SO
S16-8
MAX4508EPE+
-40°C to +85°C 16 Plastic DIP
P16-4
MAX4508MJE
-40°C to +85°C
16 CERDIP** J16-3
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
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)
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.
(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_ (Note 1) .............................. (V+ + 0.3V) to (V- - 0.3V)
NO_.........................................................(V+ - 40V) to (V- + 40V)
NO_ to COM_ ..........................................................-36V to +36V
NO_ Overvoltage with Switch Power On. ................-30V to +30V
NO_ Overvoltage 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-Pin PDIP (derate 10.53mW/°C above +70°C)..........842mW
16-Pin CERDIP (derate 10.00mW/°C above +70°C).....800mW
Operating Temperature Ranges
MAX4508C_ E/MAX4509C_E...............................0°C to +70°C
MAX4508E_ E/MAX4509E_E ............................-40°C to +85°C
MAX4508MJE/MAX4509MJE..........................-55°C to +125°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.
-150 +150
-15 +75
-1 +1
COM_ On-Leakage Current
(Note 6)
-300 +300
-100 +75
nA
-2 +2
ICOM_(ON)
-100 +100
COM_ Off-Leakage Current
(Note 6)
-100 +75
-1 +1
-200 +200
-20 +75
nA
-2 +2
ICOM_(OFF)
300 400
RON
V
V- V+
VNO_
Fault-Free Analog Signal Range
(Notes 3, 4)
-50 +50
INO_(OFF)
NO_ Off-Leakage Current
(Note 6) -5 +5 nA
-0.5 +0.5
25
500 Ω
700
On-Resistance
Ω
15
ΔRON
On-Resistance Match Between
Channels (Note 5) 20
UNITSMIN TYP MAXSYMBOLPARAMETER
V+ = +15V, V- = -15V,
VNO_= ±15V
VCOM_ = ±10V,
VNO_ = ±10V or
floating
VNO_ = ±10V, VCOM_ = –
+10V
VCOM_ = ±10V, INO_ = 0.2mA
VCOM_ = ±10V, INO_ = 0.2mA
VCOM_ = ±10V,
VNO_ = –
+10V
CONDITIONS
M
C, E
+25°C
+25°C
M
C, E, M
C, E
+25°C
M
C, E
M
C, E
+25°C
M
+25°C
M
C, E
M
+25°C
C, E
C, E
+25°C
TA
MAX4508
MAX4509
MAX4508
MAX4509
ANALOG SWITCH
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
_______________________________________________________________________________________ 3
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)
VNO_ = ±25VRCOM_
ns
600
ns
Enable Turn-On Time
120 200
M
Transition Time
+25°C
500
170 350
tTRANS Figure 2 C, E, M
+25°C
VNO_ = ±10V, RL = 1kΩ,
Figures 2 and 3 nstOFF
Enable Turn-Off Time 250C, E
10 80C, E, M
VNO_ = ±10V, RL = 1kΩ,
Figure 4 ns
400M
tBBM
Break-Before-Make Time Delay
(Note 4)
UNITSMIN TYP MAXSYMBOLPARAMETER CONDITIONS TA
400
160 275
tON
µA-1 +1IA_H, IA_L
A_ Input Current Logic
High or Low
V0.8VA_L
A_ Input Logic Threshold Low
V2.4VA_H
A_ Input Logic Threshold High
µs2.5± Fault Recovery Time (Note 4)
ns20
± Fault Output Clamp Turn-On
Delay (Note 4)
COM_ On Clamp Output
Resistance, Supplies On kΩ100 1.0 2.5
COM_ On Clamp Output
Current, Supplies On -13 -11 -7 mA
71013
ICOM_
nA-20 +20
-40 +40 V
-25 +25
VNO_
Fault-Protected Analog Signal
Range (Notes 3, 4)
µA
-100 +100
nA
-5 +5
-20 +20
INO_
NO_ Input Leakage Current,
Supplies Off
µA-50 +50
INO_
NO_ Input Leakage Current,
Supplies On
-1 +1
-100 +100
ICOM_
COM_ Output Leakage Current,
Supplies On
nA
-20 +20
-200 +200
VNO_ = ±10V, RL= 1kΩ,
Figures 2 and 3
VA_= 0.8V or 2.4V
Applies with power on, Figure 9
RL= 10kΩ, VNO_ = ±25V
RL = 10kΩ, VNO_ = ±25V
VNO_= ±40V, VCOM = 0,
V+ = 0, V- = 0
VNO_= ±25V, VCOM_ = –
+10V,
VEN = 0
VNO_= ±25V, VEN = 0
VCOM = 0
C, E
+25°C
+25°C
C, E, M
C, E, M
C, E, M
+25°C
+25°C
+25°C
M
C, E
+25°C
+25°C
M
C, E
M
+25°C
C, E
+25°C
210+25°C
CL= 1.0nF, VNO_ = 0, RS= 0,
Figure 5 pCQCharge Injection (Note 4)
-70+25°C
RL= 75Ω, CL= 15pF,
VNO_ = 1VRMS, f = 1MHz, Figure 6 dBVISO
Off-Isolation (Note 7)
SWITCH DYNAMIC CHARACTERISTICS
LOGIC INPUT
FAULT PROTECTION
Applies with power off
VNO_ = +25V
VNO_ = -25V
µA
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
4 _______________________________________________________________________________________
UNITSMIN TYP MAXSYMBOLPARAMETER CONDITIONS TA
500 µA
200 300
IGND
GND Supply Current
µA
370 500
I+V+ Supply Current
±4.5 ±20
pF10
dB-62VCT
Channel-to-Channel Crosstalk
(Note 8)
19 pF
14
CN_(OFF)
NO_ Off-Capacitance
RL= 75Ω, CL= 15pF,
VNO_ = 1VRMS, f = 1MHz, Figure 7
All VA_ = 0 or 5V, VNO_ = 0,
VEN = 5V
All VA_ = 0 or 5V, VNO_ = 0,
VEN = 5V
f = 1MHz, Figure 8 +25°C
C, E, M
+25°C
+25°C
+25°C
+25°C
CCOM_(OFF)
COM_ Off-Capacitance
f = 1MHz, Figure 8CCOM_(ON)
COM_ On-Capacitance 28 pF
22
+25°C
Power-Supply Range V+, V- C, E, M V
750C, E
850M
400C, E
500M
µA
200 300
I-V- Supply Current All VA_ = 0 or 5V, VNO_ = 0,
VEN = 5V
+25°C
V
0V+
VNO_
Fault-Free Analog Signal Range
(Note 3)
-200 +200
INO_(OFF)
NO_ Off-Leakage Current
(Notes 6, 9) -10 +10 nA
-0.5 0.01 +0.5
75
Ω
10 35
ΔRON
On-Resistance Match Between
Channels (Note 5) 50
UNITSMIN TYP MAXSYMBOLPARAMETER
V+ = 12V, V- = 0, VNO_ = 12V
VCOM_ = 10V, 1V;
VNO_ = 1V, 10V
VCOM_ = 10V, INO_ = 200µA
CONDITIONS
C, E, M
M
C, E
+25°C
M
+25°C
C, E
TA
650 950
RON 1100 Ω
1300
On-Resistance VCOM_ = +10V, INO_ = 200µA
+25°C
C, E
M
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)
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)
ANALOG SWITCH
POWER SUPPLY
f = 1MHz, Figure 8 MAX4508
MAX4509
MAX4508
MAX4509
µA
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
_______________________________________________________________________________________ 5
MAX4508
MAX4508
VNO_ = 25V, V+= 12V
MAX4509
RCOM_
MAX4509
-150 +150
-15 +75
-1 +1
COM_ On-Leakage Current
(Note 6)
-300 +300
-100 +75
nA
-2 +2
ICOM_(ON)
-100 +100
COM_ Off-Leakage Current
(Note 6)
-10 +75
-1 +1
-200 +200
-20 +75
nA
-2 +2
ICOM_(OFF)
UNITSMIN TYP MAXSYMBOLPARAMETER
VCOM_ = 10V, 1V;
VNO_ = 10V, 1V, or
floating
VCOM_ = 10V, 1V;
VNO_ = 1V, 10V
CONDITIONS
M
C, E
+25°C
M
C, E
+25°C
M
C, E
+25°C
M
C, E
+25°C
TA
µA-1 0.03 +1
IINH_,
IINL_
A_ Input Current Logic
High or Low
V0.8 1.8VIN_L
A_ Input Logic Threshold Low
V1.8 2.4VIN_H
A_ Input Logic Threshold High
COM_ ON Output Resistance,
Supply On kΩ2.4 6
COM_ ON Output Current,
Supply On mA235ICOM_
-20 +20
V
-25 +25
VNO_
Fault-Protected Analog Signal
Range (Notes 3, 10)
-100 +100
nA
-5 +5
-20 0.1 +20
INO_
NO_ Input Leakage Current,
Supply Off (Notes 3, 10)
µA
-100 +100
INO_
NO_ Input Leakage Current,
Supply On (Notes 3, 10)
-1 +1 µA
-100 +100
ICOM_
COM_ Output Leakage Current,
Supply On (Notes 3, 10)
-20 +20
-5 +5
VIN_= 0.8V or 2.4V
Applies with all power on
VNO_= ±40V, V+ = 0, V- = 0
VNO_ = ±25V, VCOM_ = 0,
V+ = 12V
VNO_ = ±25V, V+ = 12V
VNO_ = 25V, V+= 12V
+25°C
C, E, M
C, E, M
C, E, M
+25°C
M
C, E
+25°C
+25°C
M
C, E
M
+25°C
C, E
+25°C
nA
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)
FAULT PROTECTION
LOGIC INPUT
Applies with all power off -40 +40
nA
µA
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
6 _______________________________________________________________________________________
COM_ On-Capacitance CCOM_(ON) VCOM_ = VNO_ = 0, f = 1MHz,
Figure 8 +25°C 28
COM_ Off-Capacitance CCOM_(OFF) pFVCOM_ = 0, f = 1MHz, Figure 8 +25°C 19
NO_ Off-Capacitance CNO_(OFF) pFVNO_ = 0, f = 1MHz, Figure 8 +25°C 10
+25°C
+25°C
All VA_ = 0 or 5V,
VNO_ = 0, VEN = 5V
RL= 75Ω, CL= 15pF,
VNO_ = 1VRMS, f = 1MHz, Figure 7
Channel-to-Channel Crosstalk
(Note 8) VCT -62 dB
936
V+ Supply Current I+
200 300
µA
C, E, M
VC, E, MV+Power-Supply Range
675
+25°C
C, E, M
VCOM_ = 10V, RL = 2kΩ,
Figure 3
tON
220 500
700
TA
CONDITIONSPARAMETER SYMBOL MIN TYP MAX UNITS
Off-Isolation
(Note 7) VISO dB
Break-Before-Make Time Delay
(Note 4)
RL= 75Ω, CL= 15pF,
VNO_ = 1VRMS, f = 1MHz, Figure 6
tBBM
+25°C -70
ns
VCOM_ = 10V, RL = 2kΩ,
Figure 4
Charge Injection
(Note 4)
+25°C 50 100
C, E, M
Q
350
Enable Turn-Off Time tOFF ns
VCOM_ = 10V, RL = 2kΩ,
Figure 3
+25°C 100 250
Enable Turn-On Time ns
pC
CL= 1.0nF, VNO_ = 0, RS= 0,
Figure 5 +25°C 210
pF
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)
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.
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: Off-Isolation = 20log10 (VCOM_ / VNO_ ), where VCOM_ = output and VNO_ = input to off switch.
Note 8: Between any two analog inputs.
Note 9: Leakage testing for single-supply operation is guaranteed by testing with dual supplies.
Note 10: Guaranteed by testing with dual supplies.
+25°C
All VA_ = 0 or V+,
VNO_ = 0, VEN = 0 or V+
100 250
C, E, M 375
SWITCH DYNAMIC CHARACTERISTICS
POWER SUPPLY
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
_______________________________________________________________________________________ 7
Typical Operating Characteristics
(V+ = +15V, V- = -15V, VEN = +2.4V, TA= +25°C, unless otherwise noted.)
0
200
100
400
300
600
500
700
900
800
1000
-20 -10 -5-15 0 5 10 15 20
ON-RESISTANCE vs.
VCOM (DUAL SUPPLIES)
MAX4508/09toc01
VCOM (V)
RON (Ω)
V+ = +15V
V- = -15V
V+ = +10V
V- = -10V
V+ = +20V
V- = -20V
V+ = +4.5V
V- = -4.5V
0
200
100
400
300
600
500
700
900
800
1100
1000
010155 2025303540
ON-RESISTANCE vs.
VCOM (SINGLE SUPPLY)
MAX4508/09toc02
VCOM (V)
RON (Ω)
V+ = +9V
V+ = +15V
V+ = +20V
V+ = +30V
V+ = +36V
V+ = +12V
0
200
100
400
300
500
600
-15 -5 0-10 5 10 15
ON-RESISTANCE vs. VCOM AND
TEMPERATURE (DUAL SUPPLIES)
MAX4508/09toc03
VCOM (V)
RON (Ω)
V+ = +15V
V- = -15V
+125°C
+25°C
+70°C
-55°C
-40°C
+85°C
0
300
200
100
500
400
900
800
700
600
1000
02468101214
ON-RESISTANCE vs. VCOM AND
TEMPERATURE (SINGLE SUPPLY)
MAX4508/09toc04
VCOM (V)
RON (Ω)
V+ = +12V
V- = 0 +125°C
-55°C
+70°C
-40°C
+85°C
+25°C
0.1p
1p
100p
10p
10n
100n
1n
1μ
-55 -5 20-30 45 70 95 120 145
LEAKAGE CURRENT vs. TEMPERATURE
MAX4508/09toc05
TEMPERATURE (°C)
LEAKAGE (A)
V+ = +15V
V- = -15V
VCOM = 10V
VNO = ±10V
ICOM_OFF
ICOM_ON
INO_OFF
±
0
0.5
1.5
1.0
2.0
2.5
-15 -5-10 0 5 10 15
CHARGE INJECTION vs. VCOM
MAX4508/09toc06
VCOM (V)
Q (pC)
V+ = +15V
V- = -15V
DUAL
SUPPLIES
SINGLE
SUPPLY
0
200
100
300
600
700
500
400
800
0 ±4±6±8±10±2 ±12 ±14 ±16 ±18 ±20
ENABLE ON AND OFF TIMES vs.
SUPPLY VOLTAGE (DUAL SUPPLIES)
MAX4508/09toc07
SUPPLY VOLTAGE (V)
tON, tOFF (ns)
VNO_ = ±10V
tON
tOFF
0
100
50
200
150
300
250
350
010155 20253035
ENABLE ON AND OFF TIMES vs.
SUPPLY VOLTAGE (SINGLE SUPPLY)
MAX4508/09toc08
SUPPLY VOLTAGE (V)
tON, tOFF (ns)
VNO_ = +10V
tON
tOFF
0
100
50
200
150
250
300
-55 5 35-25 65 95 125
ENABLE ON AND OFF TIMES
vs. TEMPERATURE
MAX4508/09toc09
TEMPERATURE (°C)
V+ = +15V
V- = -15V
tON
tOFF
tON, tOFF (ns)
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
8 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(V+ = +15V, V- = -15V, VEN = +2.4V, TA= +25°C, unless otherwise noted.)
-300
-200
-100
0
100
200
300
-55 -5-30 20 45 70 95 120 145
POWER-SUPPLY CURRENT
vs. TEMPERATURE (VA = 0)
MAX4508/09toc10
TEMPERATURE (°C)
I+, I-, IGND (μA)
V+ = +15V
V- = -15V
VA = 0
I-
IGND
I+
-600
0
-200
-400
200
400
600
-60 200-40 -20 40 60 80 100 120 140
POWER-SUPPLY CURRENT
vs. TEMPERATURE (VA = +5V)
MAX4508/09toc11
TEMPERATURE (°C)
SUPPLY CURRENT I+, I-, IGND (μA)
V+ = +15V
V- = -15V
VA = +5V
I-
IGND
I+
0
0.5
1.0
1.5
2.0
2.5
3.0
0105 152025303540
LOGIC-LEVEL THRESHOLD
vs. SUPPLY VOLTAGE
MAX4508/09toc12
SUPPLY VOLTAGE (V)
LOGIC-LEVEL THRESHOLD (V)
V- = GND
DUAL
SUPPLIES
SINGLE
SUPPLY
FREQUENCY RESPONSE
MAX4508/09taoc13
FREQUENCY (MHz)
LOSS (dB)
20
-100
-80
-60
-40
-20
0
0.001 1 10 1000.01 0.1 1000
V+ = +15V
V- = -15V
BANDWIDTH
CROSSTALK
OFF-ISOLATION
5μs/div
FAULT-FREE SIGNAL PERFORMANCE
IN_
10V/div
10V/div
0V
0V
COM_
FAULT-FREE RAIL-TO-RAIL SIGNAL HANDLING
WITH ±15V SUPPLIES
+15V
+15V
-15V
-15V
MAX4508/09toc14
5μs/div
INPUT OVERVOLTAGE vs. OUTPUT CLAMPING
IN_
0V
COM_
±25V OVERVOLTAGE INPUT WITH THE OUTPUT
CLAMPED AT ±15V
-15V
-25V
+25V
+15V
0V0V
MAX4508/09toc16
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
Detailed Description
Traditional fault-protected multiplexers are constructed
with three series FET switches. This produces good off
protection, but limits the switches input voltage range
to as much as 3V below the supply rails, reducing its
usable dynamic range. As the voltage on one side of
the switch approaches within about 3V of either supply
rail (a fault condition), the switch impedance increases,
limiting the output signal range to approximately 3V
less than the appropriate polarity supply voltage.
The MAX4508/MAX4509 differ considerably from tradi-
tional fault-protected multiplexers, offering several
advantages. First, they are constructed with two paral-
lel FETs, allowing very low resistance when the switch
is on. Second, they allow signals on the NO_ pins that
are within or beyond the supply rails to be passed
through the switch to the COM terminal. This allows rail-
to-rail signal operation. Third, when a signal VNO_
exceeds the supply rails (i.e., a fault condition), the
voltage on COM_ is limited to the supply rails.
Operation is identical for both fault polarities.
Pin Descriptions
Truth Tables
NAME FUNCTION
1A0 Address Bit 0
2EN Mux Enable
PIN
3V- Negative Supply Voltage
4NO1 Channel Input 1
8COM Analog Output
7NO4 Channel Input 4
6NO3 Channel Input 3
5NO2 Channel Input 2
12 NO5 Channel Input 5
11 NO6 Channel Input 6
10 NO7 Channel Input 7
9NO8 Channel Input 8
13 V+ Positive Supply Voltage
14 GND Ground
15 A2 Address Bit 2
16 A1 Address Bit 1
MAX4508 (Single 8-to-1 Mux) MAX4509 (Dual 4-to-1 Mux)
NAME FUNCTION
1A0 Address Bit 0
2EN Mux Enable
PIN
3V- Negative Supply Voltage
4 NO1A Channel Input 1A
8 COMA Mux Output A
7 NO4A Channel Input 4A
6 NO3A Channel Input 3A
5 NO2A Channel Input 2A
13 NO1B Channel Input 1B
12 NO2B Channel Input 2B
11 NO3B Channel Input 3B
10 NO4B Channel Input 4B
9 COMB Mux Output B
14 V+ Positive Supply Voltage
15 GND Ground
16 A1 Address Bit 1
x x None
0 0 NO1
0 0 NO2
0 1 NO3
1 1 NO7
1 0 NO6
1 0 NO5
0 1 NO4
1 1 NO8
x
0
1
0
0
1
0
1
1
0
1
1
1
1
1
1
1
1
A1 ON SWITCHA2 A0 EN
MAX4508 (Single 8-to-1 Mux)
x None
0 NO1A
0 NO2A
1 NO3A
1 NO4A
x
0
1
0
1
0
1
1
1
1
A1 COMAA0 EN
MAX4509 (Dual 4-to-1 Mux)
None
NO1B
NO2B
NO3B
NO4B
COMB
_______________________________________________________________________________________ 9
MAX4508/MAX4509
When the NO_ voltage goes beyond supply rails (fault
condition), the NO_ input becomes high impedance
regardless of the switch state or load resistance. When
power is removed, and the fault protection is still in
effect, the NO_ terminals are a virtual open circuit. The
fault can be up to ±40V, with V+ = V- = 0. If the switch
is on, the COM_ output current is furnished from the V+
or V- pin by “booster” FETs connected to each supply
pin. These FETs can source or sink up to 10mA.
The COM_ pins are not fault protected. If a voltage
source is connected to any COM_ pin, it should be lim-
ited to the supply voltages. Exceeding the supply volt-
age will cause high currents to flow through the ESD
protection diodes, damaging the device (see Absolute
Maximum Ratings).
Figure 1 shows the internal construction, with the ana-
log signal paths shown in bold. A single normally open
(NO) switch is shown. The analog switch is formed by
the parallel combination of N-channel FET N1 and P-
channel FET P1, which are driven on and off simultane-
ously, according to the input fault condition and the
logic level state.
NO_ Input Voltage
The maximum allowable input voltage for safe opera-
tion depends on whether supplies are on or off and the
load configuration at the COM output. If COM is re-
ferred to a voltage other than ground, but within the
supplies, VNO_ may range higher or lower than the sup-
plies provided the absolute value of ⎢VNO_ - VCOM_⎢is
less than 40V. For example, if the load is referred to
+10V at COM_, then the NO_ voltage range can be
from +50V to -30V. As another example, if the load is
connected to -10V at COM_, the NO_ voltage range is
limited to -50V to +30V.
If the supplies are ±15V and COM is referenced to
ground through a load, the maximum NO_ voltage is
±25V. If the supplies are off and the COM output is ref-
erenced to ground, the maximum NO_ voltage is ±40V.
Normal Operation
Two comparators continuously compare the voltage on
the NO_ pin with V+ and V- supply voltages. When the
signal on NO_ is between V+ and V-, the multiplexer
behaves normally, with FETs N1 and P1 turning on and
off in response to A_ signals (Figure 1). The parallel
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
10 ______________________________________________________________________________________
NORMALLY OPEN SWITCH CONSTRUCTION
COM_
P2
P1
N1
ON
LOW
FAULT
HIGH
FAULT
V+
NO_
A-
GWD
ESO CODE
V- N2
MAX4508
MAX4509
Figure 1. Functional Diagram
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
______________________________________________________________________________________ 11
combination of N1 and P1 forms a low-value resistor
between NO_ and COM_ so that signals pass equally
well in either direction.
Positive Fault Condition
When the signal on NO_ exceeds V+ by about 150mV,
the positive fault comparator output goes high, turning
off FETs N1 and P1 (Figure 1). This makes the NO_ pin
high impedance, regardless of the switch state. If the
switch state is “off,” all FETs turn off, and both NO_ and
COM_ are high impedance. If the switch state is “on,”
FET P2 turns on, clamping COM_ to V+.
Negative Fault Condition
When the signal on NO_ goes about 150mV below V-,
the negative fault comparator output goes high, turning
off FETs N1 and P1 (Figure 1). This makes the NO_ pin
high impedance, regardless of the switch state. If the
switch state is “off,” all FETs turn off, and both NO_ and
COM_ are high impedance. If the switch state is “on,”
FET N2 turns on, clamping COM_ to V-.
Transient Fault Condition
When a fast rising or falling transient on NO_ exceeds
V+ or V-, the output (COM_) follows the input (NO_) to
the supply rail with only a few nanoseconds delay. This
delay is due to the switch on-resistance and circuit
capacitance to ground. When the input transient
returns to within the supply rails, however, there is a
longer output recovery time. For positive faults, the
recovery time is typically 2.5µs (see Typical Operating
Characteristics). For negative faults, the recovery time
is typically 1.3µs. These values depend on the COM_
output resistance and capacitance. The delays do not
depend on the fault amplitude. Higher COM_ output
resistance and capacitance increase the recovery
times.
COM and A_
FETs N2 and P2 can source about ±10mA from V+ or
V- to the COM_ pin in the fault condition (Figure 1).
Ensure that if the COM_ pin is connected to a low-
impedance load, the absolute maximum current rating
of 30mA is never exceeded, either in normal or fault
conditions.
The GND, COM_, and A_ pins do not have fault protec-
tion. Reverse ESD protection diodes are internally con-
nected between GND, COM_, A_, and both V+ and V-.
If a signal on GND, COM_, or A_ exceeds V+ or V- by
more than 300mV, one of these diodes will conduct.
During normal operation, these reverse-biased ESD
diodes leak a few nanoamps of current to V+ and V-
Fault Protection Voltage and Power Off
The maximum fault voltage on the NO_ pins is ±40V
from ground when the power is off. With ±15V supply
voltages, the highest voltage on NO_ can be V- + 40V,
and the lowest voltage on NO can be V+ - 40V.
Exceeding these limits can damage the chip.
Logic Level Thresholds
The logic level thresholds are CMOS and TTL compati-
ble with V+ = 13.5V to V+ = 16.5V.
Applications Information
Ground
There is no connection between the analog signal
paths and GND. The analog signal paths consist of an
N-channel and a P-channel MOSFET with their sources
and drains paralleled and their gates driven out of
phase to V+ and V- by the logic-level translators.
V+ and GND power the internal logic and logic level
translators and set the input logic thresholds. The logic-
level translators convert the logic levels to switched V+
and V- signals to drive the gates of the multiplexers.
This drive signal is the only connection between the
power supplies and the analog signals. GND, A_, and
COM_ have ESD protection diodes to V+ and V-.
Supply Current Reduction
When the logic signals are driven rail-to-rail from 0 to
+15V or -15V to +15V, the current consumption will be
reduced from 370µA (typ) to 200µA.
Power Supplies
The MAX4508/MAX4509 operate with bipolar supplies
between ±4.5V and ±20V. The V+ and V- supplies
need not be symmetrical, but their sum cannot exceed
the 44V absolute maximum rating.
The MAX4508/MAX4509 operate from single supplies
between +9V and +36V when V- is connected to GND.
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
12 ______________________________________________________________________________________
50%
tOFF(EN)
tR < 20ns
tF < 20ns
+3V
0V
0V
LOGIC
INPUT
VEN
SWITCH
OUTPUT
VOUT
+15V
VOUT
-15V
GND
V+
A1
V-
A0
A2
EN NO1
NO2–NO8
COM
+10V
50Ω
MAX4508
1k 35pF
90%
10%
tON(EN)
+15V
VOUT
-15V
GND
V+
A1
V-
A0
EN NO1B
NO1A–NO4A
NO2B–NO4B,
COMA
COMB
+10V
50Ω
MAX4509
1k 35pF
VEN
VEN
Figure 2. Address Transition Time
Figure 3. Enable Switching Time
Test Circuits/Timing Diagrams
50%
tTRANS
tR < 20ns
tF < 20ns
VOUT
+3V
0V
VNO1
0V
VNO8
LOGIC
INPUT
VA_
SWITCH
OUTPUT
+15V
VOUT
-15V
GND
V+
A1
V-
A2
A0
EN
NO1
NO2–NO7
NO8
COM
+10V
-10V
50Ω
MAX4508
1k
35pF
+15V
VOUT
-15V
GND
V+
A0
V-
A1
EN
NO1B
NO1A–NO4A
NO4B
COMB
+10V
50Ω
MAX4509
300Ω35pF
90%
90%
tTRANS
ON
-10V
+2.4V
+2.4V
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
______________________________________________________________________________________ 13
50%
tOPEN
tR < 20ns
tF < 20ns
+5V
+3V
0V
LOGIC
INPUT
VA
SWITCH
OUTPUT
VOUT
+15V
VOUT
-15V
GND
V+
A0
V-
A1
A2
EN
NO1–NO8
COM
+10V
50Ω
MAX4508
1k
35pF
80%
+2.4V
0V
VA
VEN
ΔVOUT
+3V
0V
LOGIC
INPUT
VEN
+15V
VOUT
-15V
GND
V+
A1
V-
A0
A2
EN
COM
MAX4508
CL
1000nF VOUT
NO
CHANNEL
SELECT
RS
VS
ONOFF OFF
ΔVOUT IS THE MEASURED VOLTAGE DUE TO CHARGE TRANSFER
ERROR VCTE WHEN THE CHANNEL TURNS OFF.
VCTE = ΔVOUT CL
VEN
+15V
VOUT
-15V
GND
V+
A1
V-
A0
A2
NO8
COM
MAX4508
NO1
RS = 50Ω
VIN
EN
10nF
RL
75Ω
OFF-ISOLATION = 20log VOUT
VIN
10nF
+15V
VOUT
-15V
GND
V+
A1
V-
A0
A2
NO8
COM
MAX4508
NO2
RG = 50Ω
VIN
EN
10nF
RL
75Ω
10nF
NO1
R
1kΩ
CROSSTALK = 20log VOUT
VIN
Figure 4. MAX4508 Break-Before-Make Interval
Figure 5. Charge Injection
Figure 6. Off-Isolation Figure 7. Crosstalk
Test Circuits/Timing Diagrams (continued)
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
14 ______________________________________________________________________________________
+15V
-15V
GND
V+
A2
V-
A1
A0
NO8
MAX4508
CHANNEL
SELECT
NO1
COM
EN
1MHz
CAPACITANCE
ANALYZER
f = 1MHz
+25V
-25V
-15V
+15V
VCOM_
VNO_
Figure 8. NO_, COM_ Capacitance Figure 9. Transient Behavior of Fault Condition
Test Circuits/Timing Diagrams (continued)
Functional Diagrams/Truth Tables
DECODERS/DRIVERS
COMA
NO1A
NO2A
NO3A
NO4A
A0 A1 EN
V+ V- GND
MAX4509
COMB
NO1B
NO2B
NO3B
NO4B
A0A1 EN ON SWITCH
X
0
0
1
1
X
0
1
0
1
0
1
1
1
1
NONE
1
2
3
4
LOGIC "0" VAL ≤ +0.8V, LOGIC "1" VAH ≥ +2.4V
MAX4509
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
_______________________________________________________________________________________ 15
Chip Topography
SUBSTRATE IS INTERNALLY CONNECTED TO V+
0.198"
(5.03mm)
0.086"
(2.18mm)
V-
N01
N02
N03
N04 N08
COM
N07
N.C.
N06
N05
V+
GND
EN A0 A1 A2
*Contact factory for dice specifications.
**Contact factory for availability.
+Denotes a lead-free package.
Ordering Information (continued)
PART TEMP
RANGE
PIN-
PACKAGE
PKG
CODE
MAX4509CSE+
0°C to +70°C 16 Narrow SO
S16-8
MAX4509CPE+
0°C to +70°C 16 Plastic DIP
P16-4
MAX4509C/D
0°C to +70°C
Dice* —
MAX4509ESE+
-40°C to +85°C 16 Narrow SO
S16-8
MAX4509EPE+
-40°C to +85°C 16 Plastic DIP
P16-4
MAX4509MJE
-40°C to +85°C
16 CERDIP** J16-3
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
16 ______________________________________________________________________________________
SOICN .EPS
PACKAGE OUTLINE, .150" SOIC
1
1
21-0041 B
REV.DOCUMENT CONTROL NO.APPROVAL
PROPRIETARY INFORMATION
TITLE:
TOP VIEW
FRONT VIEW
MAX
0.010
0.069
0.019
0.157
0.010
INCHES
0.150
0.007
E
C
DIM
0.014
0.004
B
A1
MIN
0.053A
0.19
3.80 4.00
0.25
MILLIMETERS
0.10
0.35
1.35
MIN
0.49
0.25
MAX
1.75
0.050
0.016L0.40 1.27
0.3940.386D
D
MINDIM
D
INCHES
MAX
9.80 10.00
MILLIMETERS
MIN MAX
16 AC
0.337 0.344 AB8.758.55 14
0.189 0.197 AA5.004.80 8
N MS012
N
SIDE VIEW
H 0.2440.228 5.80 6.20
e 0.050 BSC 1.27 BSC
C
HE
eBA1
A
D
0∞-8∞
L
1
VARIATIONS:
PDIPN.EPS
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.)
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
______________________________________________________________________________________ 17
CDIPS.EPS
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.)
MAX4508/MAX4509
Fault-Protected, High-Voltage Single 8-to-1/
Dual 4-to-1 Multiplexers with Output Clamps
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.
18 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2007 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.
Revision History
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
5 10/07 EC table changes and stylistic corrections 2–5