Maxim MAX4520EUA Rail-to-rail, fault-protected, spst analog switch Datasheet

19-1542; Rev 0; 10/99
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
On-resistance is 160Ω max. The off-leakage current is
only 0.5nA at +25°C and 10nA at +85°C. The MAX4510
is a normally closed switch, while the MAX4520 is a
normally open switch. These CMOS switches operate
with dual power supplies ranging from ±4.5V to ±20V
or a single supply between +9V and +36V.
The digital input has +0.8V and +2.4V logic thresholds,
ensuring both TTL- and CMOS-logic compatibility when
using ±15V or a single +12V supply. The MAX4510/
MAX4520 are available in 6-pin SOT23 and 8-pin µMAX
packages.
Features
♦ ±40V Fault Protection with Power Off
±36V Fault Protection with ±15V Supplies
♦ Switch is Off with Power Removed
♦ Rail-to-Rail Signal Handling
♦ 160Ω max Signal Paths with ±15V Supplies
♦ On-Switch Turns Off with Overvoltage
♦ 0.5nA Off-Leakage Current
♦ Output Clamped to Appropriate Supply Voltage
During Fault Condition; No Transition Glitch
♦ No Power-Supply Sequencing Required
♦ ±4.5V to ±20V Dual Supplies
+9V to +36V Single Supply
♦ Low Power Consumption: <2mW
♦ TTL- and CMOS-Compatible Logic Inputs with
Single +9V to +15V or ±15V Supplies
Pin Configurations/Truth Tables
Applications
Data Acquisition
TOP VIEW
Industrial and Process-Control Systems
Avionics
V+
1
V-
2
IN
3
ATE Equipment
Redundant/Backup Systems
MAX4510
MAX4520
6
NC (NO)
5
COM
4
GND
SOT23
Ordering Information
( ) ARE FOR MAX4520.
TEMP. RANGE
PINPACKAGE
TOP
MARK
MAX4510EUT-T -40°C to +85°C
6 SOT23-6
AABZ
MAX4510EUA
8 µMAX
PART
-40°C to +85°C
MAX4520EUT-T -40°C to +85°C
MAX4520EUA
-40°C to +85°C
6 SOT23-6
8 µMAX
—
IN
MAX4510
MAX4520
0
ON
OFF
1
OFF
ON
AADK
—
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
SWITCHES SHOWN FOR LOGIC "0" INPUT.
ALL SWITCHES ARE OFF WITH POWER REMOVED.
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
MAX4510/MAX4520
General Description
The MAX4510/MAX4520 single-pole/single-throw (SPST),
fault-protected analog switches feature a fault-protected
input and Rail-to-Rail® signal-handling capability. The
normally open (NO) and normally closed (NC) terminals
are protected from overvoltage faults up to 36V during
power-on and 44V with power off. During a fault condition, the switch input terminal (NO or NC) becomes an
open circuit; only nanoamperes of leakage current flow
from the fault source, and the switch output (COM) furnishes up to 13mA of the appropriate polarity supply
voltage to the load. This ensures unambiguous rail-to-rail
outputs when a fault begins and ends.
MAX4510/MAX4520
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
ABSOLUTE MAXIMUM RATINGS
(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, IN (Note 1)..................................(V- - 0.3V) to (V+ + 0.3V)
NC, NO (Note 2) .....................................(V+ - 36V) to (V- + 36V)
NC, NO to COM.......................................................-36V to +36V
Continuous Current into Any Terminal..............................±30mA
Peak Current into Any Terminal
(pulsed at 1ms, 10% duty cycle)...................................±50mA
Continuous Power Dissipation (TA = +70°C) (Note 2)
6-Pin SOT23-6 (derate 7.1mW/°C above +70°C) .........696mW
8-Pin µMAX (derate 4.10mW/°C above +70°C) ............330mW
Operating Temperature Ranges
MAX45_0EUT....................................................-40°C to +85°C
MAX45_0EUA ...................................................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
Note 1: COM and IN pins are not fault protected. Signals on COM or IN exceeding V+ or V- are clamped by internal diodes. Limit
forward diode current to maximum current rating.
Note 2: NC and NO pins are fault protected. Signals on NC or NO exceeding -36V to +36V may damage the device. These limits
apply with power applied to V+ or V-, or ±40V with V+ = V- = 0.
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, GND = 0, VIH = 2.4V, VIL = 0.8V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA =
+25°C.) (Note 3)
PARAMETER
SYMBOL
CONDITIONS
TA
MIN
E
V-
TYP
MAX
UNITS
V+
V
ANALOG SWITCH
Fault-Free Analog Signal Range
On-Resistance
VNO, VNC
Applies with power on or off
RON
VCOM = ±10V, ICOM = 1mA
+25°C
125
E
160
225
NO or NC Off-Leakage Current
(Notes 4, 5)
INO(OFF),
INC(OFF)
VCOM = ±14V;
–
VNO, VCOM = +14V
+25°C
-0.5
E
-10
COM Off-Leakage Current
(Notes 4, 5)
ICOM(OFF)
VCOM = ±14V;
– 14V
VNO, VNC = +
+25°C
-0.5
E
-10
COM On-Leakage Current
(Notes 4, 5)
ICOM(ON)
VCOM = ±14V; VNO, VNC =
±14V or unconnected
+25°C
-0.5
E
-20
0.01
0.5
10
0.01
0.5
10
0.01
0.5
20
Ω
nA
nA
nA
FAULT (V+ = +15V, V- = -15V, unless otherwise noted.)
-36
36
-40
40
+25°C
-10
10
E
-200
200
VNO, VNC
COM Off-Leakage Current,
Supplies On
ICOM(OFF)
VNO or VNC = ±36V
NO or NC Input Leakage
Current, Supplies On
INO, INC
VNO or VNC = ±36V,
– 10V
VCOM = +
+25°C
-20
20
E
-200
200
NO or NC Input Leakage
Current, Supplies Off
INO, INC
VNO or VNC = ±40V,
V+ = 0, V- = 0
+25°C
-20
E
-200
Clamp Output Current,
Supplies On
2
Applies with power on (Note 6)
Fault-Protected Analog
Signal Range
ICOM
Applies with power off (Note 6)
VNO or VNC = 36V
VNO or VNC = -36V
E
+25°C
0.1
20
200
8
11
13
-12
-10
-7
_______________________________________________________________________________________
V
nA
nA
nA
mA
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
(V+ = +15V, V- = -15V, VIH = 2.4V, VIL = 0.8V, GND = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA =
+25°C.) (Note 3)
PARAMETER
Clamp Output Resistance,
Supplies On
SYMBOL
RCOM
CONDITIONS
VNO or VNC = ±36V
Fault Trip Threshold
TA
MIN
+25°C
TYP
1
E
+25°C
MAX
2.5
3
V- - 0.4
V+ + 0.4
UNITS
kΩ
V
Fault Output Turn-On
Delay Time
VIN = ±25V, RL = 10kΩ
+25°C
10
ns
Fault Recovery Time
VIN = ±25V, RL = 10kΩ
+25°C
2.5
µs
LOGIC INPUT
IN Input Logic High
VINH
E
IN Input Logic Low
VINL
E
IN Input Current
IINH, IINL
VIN = 0.8V or 2.4V
2.4
V
0.8
+25°C
-1
E
-5
0.03
1
5
V
µA
SWITCH DYNAMIC CHARACTERISTICS
Turn-On Time
tON
VNO or VNC = ±10V, RL = 2kΩ,
CL = 35pF, Figure 2
+25°C
Turn-Off Time
tOFF
VNO or VNC = ±10V, RL = 2kΩ,
CL = 35pF, Figure 2
+25°C
Charge Injection (Note 7)
NO or NC Off-Capacitance
350
E
500
600
60
E
175
250
Q
CL = 1nF, VNO = 0,
RS = 0Ω, Figure 3
+25°C
1.5
5
ns
ns
pC
CN(OFF)
f = 1MHz, Figure 4
+25°C
10
pF
COM Off-Capacitance
CCOM(OFF)
f = 1MHz, Figure 4
+25°C
5
pF
COM On-Capacitance
CCOM(ON)
f = 1MHz, Figure 4
+25°C
10
pF
RL = 50Ω, CL = 15pF,
VN_ = 1VRMS, f = 1MHz, Figure 5
+25°C
-62
dB
Off-Isolation (Note 8)
VCISO
POWER SUPPLY
Power-Supply Range
V+, V-
E
V+ Supply Current
I+
VIN = 0 or 5V
V- Supply Current
I-
VIN = 0 or 5V
VIN = 0 or 15V
GND Supply Current
IGND
VIN = 5V
±4.5
+25°C
±20
100
E
+25°C
50
E
+25°C
E
100
175
-1
0.01
E
+25°C
175
250
µA
µA
1
10
50
V
100
µA
175
_______________________________________________________________________________________
3
MAX4510/MAX4520
ELECTRICAL CHARACTERISTICS—Dual Supplies (continued)
MAX4510/MAX4520
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
ELECTRICAL CHARACTERISTICS—Single +12V Supply
(V+ = +12V, V- = 0, GND = 0, VIH = 2.4V, VIL = 0.8V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
(Note 3)
PARAMETER
SYMBOL
CONDITIONS
TA
MIN
E
0
TYP
MAX
UNITS
V+
V
260
390
ANALOG SWITCH
Fault-Free Analog Signal Range
On-Resistance
VNO, VNC
RON
Applies with power on or off
VCOM = 10V,
ICOM = 1mA
+25°C
E
500
NO or NC Off-Leakage Current
(Notes 4, 5, 9)
INO(OFF),
INC(OFF)
VCOM = 10V, 1V;
VNO, VNC = 1V, 10V
+25°C
-0.5
0.01
0.5
E
-10
COM Off-Leakage Current
(Notes 4, 5, 9)
ICOM(OFF)
VCOM = 1V, 10V;
VNO, VNC = 10V, 1V
+25°C
-0.5
E
-10
COM On-Leakage Current
(Notes 4, 5, 9)
ICOM(ON)
VCOM = 1V, 10V; VNO, VNC =
1V, 10V, or unconnected
+25°C
-0.5
E
-20
20
-36
36
-40
40
10
0.01
0.5
10
0.01
0.5
Ω
nA
nA
nA
FAULT
Fault-Protected Analog
Signal Range
COM Off-Leakage Current,
Supply On
VNO, VNC
Applies with power on (Note 6)
Applies with power off (Note 6)
E
+25°C
-10
10
E
-200
200
ICOM
VNO or VNC = ±36V
NO or NC Input Leakage
Current, Supply On
INO, INC
VNO or VNC = ±36V,
VCOM = 0
+25°C
-20
20
E
-200
200
NO or NC Input Leakage
Current, Supply Off
INO, INC
VNO or VNC = ±40V,
V+ = 0, V- = 0
+25°C
-20
E
-200
2
Clamp Output Current,
Supply On
ICOM
VNO or VNC = 36V
+25°C
Clamp Output Resistance,
Supply On
RCOM
VNO or VNC = 36V
+25°C
0.1
20
200
V
nA
nA
nA
3
5
mA
2.4
5
kΩ
LOGIC INPUT
IN Input Logic High
VINH
IN Input Logic Low
VINL
E
IINH, IINL
+25°C
E
IN Input Current
4
E
VIN = 0.8V or 2.4V
2.4
V
0.8
-1
-5
0.03
_______________________________________________________________________________________
1
5
V
µA
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
(V+ = +12V, V- = 0, GND = 0, VIH = 2.4V, VIL = 0.8V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
(Note 3)
PARAMETER
SYMBOL
CONDITIONS
TA
MIN
TYP
MAX
UNITS
SWITCH DYNAMIC CHARACTERISTICS
Turn-On Time
tON
VNO or VNC = 7V, RL = 2kΩ,
CL = 35pF, Figure 2
+25°C
Turn-Off Time
tOFF
VNO or VNC = 7V, RL = 2kΩ,
CL = 35pF, Figure 2
+25°C
500
E
750
1000
60
E
200
300
ns
ns
Q
CL = 1nF, VNO = 0,
RS = 0Ω, Figure 3
+25°C
1
NO or NC Off-Capacitance
CNO(OFF),
CNC(OFF)
f = 1MHz, Figure 4
+25°C
9
pF
COM Off-Capacitance
CCOM(OFF)
VCOM = 0, f = 1MHz, Figure 4
+25°C
9
pF
COM On-Capacitance
CCOM(ON)
VCOM = VNO = 0,
f = 1MHz, Figure 4
+25°C
22
pF
RL = 50Ω, CL = 15pF,
VIN = 1VRMS, f = 1MHz, Figure 5
+25°C
-62
dB
Charge Injection (Note 7)
Off-Isolation (Note 8)
VISO
5
pC
POWER SUPPLY
Power-Supply Range
V+ Supply Current
V+
I+
E
VIN = 0 or 5V
VIN = 0 or 12V
V- and GND Supply Current
IGND
VIN = 0 or 5V
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
Note 8:
Note 9:
+25°C
9
36
50
E
+25°C
175
25
E
+25°C
E
125
75
125
50
125
175
V
µA
µA
µA
Algebraic convention is used in this data sheet; the most negative value is shown in the minimum column.
Leakage parameters are 100% tested at maximum-rated hot temperature and guaranteed by correlation at TA = +25°C.
SOT packages are 100% tested at +25°C. Limits at the maximum-rated temperature are guaranteed by design and correlation limits at +25°C. Leakage tests for the SOT package are typical only.
NC and NO pins are fault protected. Signals on NC or NO exceeding -36V to +36V may damage the device. These limits
apply with power applied to V+ or V-, or ±40V with V+ = V- = 0.
Guaranteed by design.
Off isolation = 20log10 [ VCOM / (VNC or VNO) ], VCOM = output, VNC or VNO = input to off switch.
Leakage testing for single-supply operation is guaranteed by testing with dual supplies.
_______________________________________________________________________________________
5
MAX4510/MAX4520
ELECTRICAL CHARACTERISTICS—Single +12V Supply (continued)
__________________________________________Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
SWITCH ON-RESISTANCE vs. VCOM AND
TEMPERATURE (DUAL SUPPLIES)
150
100
V+ = +15V
V- = -15V
50
140
120
100
80
60
TA = +25°C
TA = -40°C
-10
-5
0
5
10
15
-10
-5
0
5
10
VCOM (V)
VCOM (V)
SWITCH ON-RESISTANCE vs. VCOM
AND TEMPERATURE (SINGLE SUPPLY)
ID(ON), IS(OFF), AND ID(OFF)
LEAKAGES vs. TEMPERATURE
TA = +125°C
350
TA = +85°C
LEAKAGE (A)
TA = +25°C TA = -40°C
250
200
150
ICOM(ON) AT VNO
= VCOM = +14V
100p
50
0
2
4
6
8
10
12
SINGLE +12V
SUPPLY
2
-25
0
25
50
75
-15
100 125 150
-10
-5
0
5
10
ON- AND OFF-TIMES
vs. SUPPLY VOLTAGE
ON- AND OFF-TIMES
vs. TEMPERATURE
POWER-SUPPLY CURRENT vs.
TEMPERATURE
500
500
400
tOFF
(SINGLE
SUPPLY)
300
200
tOFF
(DUAL SUPPLIES)
400
300
200
tOFF
5
10
15
SUPPLY VOLTAGE (±V)
20
V+ = +15V
V- = -15V
VIN = +5V
I+
tON
15
100
IGND
50
0
-50
I-
100
-100
0
0
150
SUPPLY CURRENT (µA)
tON, tOFF (ns)
600
200
MAX4510-08
600
MAX4510-07
700
MAX4510-03
6
0
-50
tON
(SINGLE SUPPLY)
40
DUAL ±15V
SUPPLIES
8
VCOM (V)
tON
(DUAL SUPPLIES)
0
35
TEMPERATURE (°C)
900
100
30
VCOM (V)
1000
800
20 25
VCOM (V)
4
1p
0
15
V+ = +15V
V- = -15V
12
INO(OFF) AT VNO = +14V,
VCOM = -14V
V+ = +12V
10
14
INO(OFF) AT VNO = -14V,
VCOM = +14V
10p
5
10
ICOM(ON) AT VNO
= VCOM = -14V
TA = -55°C
100
0
ICOM(OFF) AT VNO = +14V,
VCOM = -14V
1n
V+ = +30V V+ = +36V
CHARGE INJECTION
vs. VCOM (DUAL SUPPLIES)
ICOM(OFF) AT VNO = -14V,
VCOM = +14V
10n
300
V+ = +24V
15
100n
MAX4510-04
400
10
1
-15
20
Q (pC)
-15
V+ = +5V
V+ = +12V
V+ = +15V
V+ = +20V
V+ = +15V
V- = -15V
20
0
-20
SWITCH ON-RESISTANCE (Ω)
TA = -55°C
40
V+ = +20V
V- = -20V
0
6
MAX4510-02
160
1000
MAX4510-06
200
TA = +85°C
SWITCH ON-RESISTANCE (Ω)
V+ = +12V
V- = -12V
V+ = +10V
V- = -10V
TA = +125°C
MAX4510-05
SWITCH ON-RESISTANCE (Ω)
250
180
SWITCH ON-RESISTANCE (Ω)
V+ = +5V
V- = -5V
300
200
MAX4510-01
350
SWITCH ON-RESISTANCE
vs. VCOM (SINGLE SUPPLY)
MAX4510/20 toc 09
SWITCH ON-RESISTANCE
vs. VCOM (DUAL SUPPLIES)
tON, tOFF (ns)
MAX4510/MAX4520
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
-150
-50
-25
0
25
50
75
TEMPERATURE (°C)
100
125
-40
-20
0
20
40
60
TEMPERATURE (°C)
_______________________________________________________________________________________
80
100
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
LOGIC-LEVEL THRESHOLD vs. V+
FREQUENCY RESPONSE
2.5
-10
MAX4510/20 TOC11
MAX4511-10
0
ON LOSS
-20
-30
2.0
LOSS (dB)
LOGIC-LEVEL THRESHOLD (V)
3.0
1.5
-40
SS
-50
F
OF
-60
LO
-70
1.0
-80
-90
0.5
V+ = +15V
V- = -15V
-100
0
-110
0
5
10
15
20
25
30
35
V+ (V)
PIN
1000
Overview of Traditional
Fault-Protected Switches
V+
Positive Supply Voltage
Input
2
5
V-
Negative Supply Voltage
Input. Connect to GND for
single-supply operation.
3
6
IN
Logic Control Digital Input
4
4
GND
Ground
5
1
COM
Analog Switch Common
Terminal
Fault-Protected Analog
Switch—normally closed
NC or NO (NC) for MAX4510;
normally open (NO) for
MAX4520
N.C.
100
FUNCTION
NAME
8
2, 7
10
Detailed Description
1
—
1
Pin Description
µMAX
3
0.1
FREQUENCY (MHz)
SOT23-6
6
0.01
No Connection. Not internally connected.
The MAX4510/MAX4520 are fault-protected CMOS
analog switches with unusual operation and construction. Traditional fault-protected switches are constructed by three series FETs. This produces good off
characteristics, but fairly high on-resistance when the
signals are within about 3V of each supply rail. As the
voltage on one side of the switch approaches within
about 3V of either supply rail (a fault condition), the
switch impedance becomes higher, limiting the output
signal range (on the protected side of the switch) to
approximately 3V less than the appropriate polarity
supply voltage.
During a fault condition, the output current that flows
from the protected side of the switch into its load comes
from the fault source on the other side of the switch. If
the switch is open or the load is extremely high impedance, the input current will be very low. If the switch is
on and the load is low impedance, enough current will
flow from the source to maintain the load voltage at 3V
less than the supply.
_______________________________________________________________________________________
7
MAX4510/MAX4520
Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
MAX4510/MAX4520
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
NORMALLY OPEN SWITCH CONSTRUCTION
V+
P2
HIGH
FAULT
P1
COM
NO
(NC)
N1
LOW
FAULT
ON
IN
GND
N2
V-ESD DIODE
NC SWITCH
MAX4510
MAX4520
Figure 1. Functional Diagram
Overview of MAX4510/MAX4520
The MAX4510/MAX4520 differ considerably from traditional fault-protection switches, with several advantages. First, they are constructed with two parallel
FETs, allowing very low on-resistance when the switch
is on. Second, they allow signals on the NC or NO pins
that are within or slightly beyond the supply rails to be
passed through the switch to the COM terminal, allowing rail-to-rail signal operation. Third, when a signal on
NC or NO exceeds the supply rails by about 50mV (a
fault condition), the voltage on COM is limited to the
appropriate polarity supply voltage. Operation is identical for both fault polarities. The fault-protection extends
to ±36V from GND.
During a fault condition, the NO or NC input pin
becomes high impedance regardless of the switch
state or load resistance. 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 typically source or sink up to 13mA.
8
When power is removed, the fault protection is still in
effect. In this case, the NO or NC terminals are a virtual
open circuit. The fault can be up to ±40V.
The COM pin is not fault protected; it acts as a normal
CMOS switch pin. If a voltage source is connected to
the COM pin, it should be limited to the supply voltages. Exceeding the supply voltage will cause high
currents to flow through the ESD protection diodes,
possibly damaging the device (see Absolute Maximum
Ratings).
Internal Construction
Internal construction is shown in Figure 1, with the analog signal paths shown in bold. A single normally open
(NO) switch is shown; the normally closed (NC) configuration is identical except the logic-level translator
becomes an inverter. The analog switch is formed by
the parallel combination of N-channel FET N1 and Pchannel FET P1, which are driven on and off simultaneously according to the input fault condition and the
logic-level state.
_______________________________________________________________________________________
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
Positive Fault Condition
When the signal on NO (or NC) exceeds V+ by about
50mV, the high-fault comparator output is high, turning
off FETs N1 and P1. This makes the NO (or NC) pin
high impedance regardless of the switch state. If the
switch state is “off,” all FETs are turned off and both NO
(or NC) and COM are high impedance. If the switch
state is “on,” FET P2 is turned on, sourcing current from
V+ to COM.
Negative Fault Condition
than 300mV, one of these diodes will conduct heavily.
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 NC or NO pins is
±36V with power applied and ±40V with power off.
Failure Modes
The MAX4510/MAX4520 are not lightning arrestors or
surge protectors.
Exceeding the fault-protection voltage limits on NO or
NC, even for very short periods, can cause the device
to fail.
Ground
There is no connection between the analog signal path
and GND. The analog signal path consists of an Nchannel and 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.
When the signal on NO (or NC) exceeds V- by about
50mV, the low-fault comparator output is high, turning
off FETs N1 and P1. This makes the NO (or NC) pin
high impedance regardless of the switch state. If the
switch state is “off,” all FETs are turned off and both NO
(or NC) and COM are high impedance. If the switch
state is “on,” FET N2 is turned on, sinking current from
COM to V-.
V+ and GND power the internal logic and logic-level
translators and set the input logic thresholds. The logiclevel translators convert the logic levels to switched V+
and V- signals to drive the gates of the analog switch.
This drive signal is the only connection between the
power supplies and the analog signal. GND, IN, and
COM have ESD-protection diodes to V+ and V-.
Transient Fault Response and Recovery
The logic-level thresholds are CMOS and TTL compatible when V+ is +15V. As V+ is raised, the threshold
increases slightly, and when V+ reaches 25V, the level
threshold is about 2.8V—above the TTL output highlevel minimum of 2.4V, but still compatible with CMOS
outputs (see Typical Operating Characteristics).
Increasing V- has no effect on the logic-level thresholds,
but it does increase the gate-drive voltage to the signal
FETs, reducing their on-resistance.
When a fast rise-time and fall-time transient on IN
exceeds V+ or V-, the output (COM) follows the input (IN)
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 delay. For positive faults, the recovery
time is typically 3.5µs. For negative faults, the recovery
time is typically 1.3µs. These values depend on the COM
output resistance and capacitance. The delays are not
dependent on the fault amplitude. Higher COM output
resistance and capacitance increase recovery times.
COM and IN Pins
FETs N2 and P2 can source about ±13mA from V+ or Vto the COM pin in the fault condition. Ensure that if the
COM pin is connected to a low-resistance load, the
absolute maximum current rating of 30mA is never
exceeded, both in normal and fault conditions.
The GND, COM, and IN pins do not have fault protection. Reverse ESD-protection diodes are internally connected between GND, COM, IN, and both V+ and V-. If a
signal on GND, COM, or IN exceeds V+ or V- by more
IN Logic-Level Thresholds
Dual Supplies
The MAX4510/MAX4520 operate with dual supplies
between ±4.5V and ±20V. The V+ and V- supplies
need not be symmetrical, but their difference cannot
exceed the absolute maximum rating of 44V.
Single Supply
The MAX4510/MAX4520 operate from a single supply
between +9V and +36V when V- is connected to GND.
_______________________________________________________________________________________
9
MAX4510/MAX4520
Normal Operation
Two comparators continuously compare the voltage on
the NO (or NC) pin with V+ and V-. When the signal on
NO or NC is between V+ and V-, the switch acts normally, with FETs N1 and P1 turning on and off in
response to IN signals. The parallel combination of N1
and P1 forms a low-value resistor between NO (or NC)
and COM so that signals pass equally well in either
direction.
MAX4510/MAX4520
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
Test Circuits/Timing Diagrams
V+
V+
NO OR NC
LOGIC
INPUT
VNO OR
VNC
t r < 20ns
t f < 20ns
+3V
50%
0V
MAX4510
MAX4520
VIN
IN
t OFF
VOUT
COM
VOUT
GND
50Ω
V-
2k
35pF
SWITCH
OUTPUT
0V
0.9 · V0UT
0.9 · VOUT
t ON
VLOGIC INPUT WAVEFORMS INVERTED FOR SWITCHES
THAT HAVE THE OPPOSITE LOGIC SENSE.
V- IS CONNECTED TO GND FOR SINGLE-SUPPLY OPERATION.
Figure 2. Switch Turn-On/Turn-Off Times
V+
V+
V+
VIN
IN
50Ω
NO OR NC
VIN
0V
MAX4510
MAX4520
COM
GND
V-
V-
V- IS CONNECTED TO GND FOR SINGLE-SUPPLY OPERATION.
VOUT
VOUT
CL
1000pF
∆ VOUT IS THE MEASURED VOLTAGE DUE TO CHARGETRANSFER ERROR Q WHEN THE CHANNEL TURNS OFF.
Q = ∆ VOUT · CL
Figure 3. Charge Injection
10
∆ VOUT
______________________________________________________________________________________
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
V+
V+
NO OR NC
MAX4510
MAX4520
IN
VIN
GND
1MHz
CAPACITANCE
ANALYZER
COM
V-
VV- IS CONNECTED TO GND FOR SINGLE-SUPPLY OPERATION.
Figure 4. COM, NO, and NC Capacitance
V+ 10nF
NETWORK
ANALYZER
V+
VIN
50Ω
50Ω
COM
MAX4510
MAX4520
VIN
VOUT
IN
NO, NC
V-
GND
MEAS
REF
50Ω
OFF-ISOLATION = 20log
VOUT
VIN
ON-LOSS = 20log
VOUT
VIN
50Ω
10nF
V-
MEASUREMENTS ARE STANDARDIZED AGAINST SHORT 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 TERMINALS.
V- IS CONNECTED TO GND FOR SINGLE-SUPPLY OPERATION.
Figure 5. Frequency Response and Off-Isolation
Chip Information
TRANSISTOR COUNT: 139
______________________________________________________________________________________
11
MAX4510/MAX4520
Test Circuits/Timing Diagrams (continued)
Pin Configurations/Functional Diagrams/Truth Tables (continued)
COM
1
8
V+
COM
1
8
V+
N.C.
2
7
N.C.
N.C.
2
7
N.C.
NC
3
6
IN
NO
3
6
IN
GND
4
5
V-
GND
4
5
V-
MAX4510
µMAX
µMAX
N.C. = NOT CONNECTED
SWITCHES SHOWN FOR LOGIC "0" INPUT.
ALL SWITCHES ARE OFF WITH POWER REMOVED.
MAX4520
IN
MAX4510
MAX4520
0
ON
OFF
1
OFF
ON
________________________________________________________Package Information
6LSOT.EPS
MAX4510/MAX4520
Rail-to-Rail, Fault-Protected,
SPST Analog Switches
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
© 1999 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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