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General Description
The MAX4578/MAX4579 are high-voltage, 8-channel CMOS multiplexers. The MAX4578 and dual 4-channel MAX4579 are ideal for precision ADC calibration and system self-monitoring applications. These calibration multiplexers (cal-muxes) have precision resistor-dividers to generate accurate voltage ratios from an input reference voltage. The reference ratios include 15/4096 and 4081/4096 of the external reference volt-age, accurate to 15 bits, and 1/2(V+) and 5/8(V+ - V-),accurate to 8 bits. The external reference voltage as well as ground can also be switched to the output. The MAX4578/MAX4579 have enable inputs and address latching. All digital inputs have 0.8V and 2.4V logic thresholds, ensuring both TTL- and CMOS-logic com-patibility when using a single +12V or dual ±15V sup-plies. Protection diodes at all inputs provide >2kV ESD rating.
The MAX4578/MAX4579 operate from a single +4.5V to +36V supply or from dual supplies of ±4.5V to ±20V.On-resistance (350?max) is matched between switch-es to 15?max. Each switch can handle Rail-to-Rail ?analog signals. The off-leakage current is 20pA at T A =+25°C and 1.25nA at T A = +85°C.
The MAX4578/MAX4579 are available in small 20-pin SSOP, SO, and DIP packages.
Applications
Data-Acquisition Systems Test Equipment Avionics
Audio Signal Routing Networking
Features
o On-Chip Gain and Offset Divider Networks Provide 15-Bit Accurate Output Ratios o On-Chip V+ to GND and V+ to V- Divider Networks Provide 8-Bit Accurate Output Ratios o 350?(max) R ON
o 12?(max) R ON Matching Between Channels o 10pC (max) Charge Injection
o Guaranteed 20pA Off-Leakage Current o Rail-to-Rail Signal Handling
o Small 20-Pin SSOP, SO, DIP Packages
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
________________________________________________________________Maxim Integrated Products
1
19-1396; Rev 0; 10/98
Ordering Information continued at end of data sheet.
Pin Configurations/ Functional Diagrams
Ordering Information
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 2_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS—Dual ±15V Supplies
(V+ = +15V ±10%, V- = -15V ±10%, logic levels = 2.4V and 0.8V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +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.
(Voltage Referenced to GND)
V+...........................................................................-0.3V to +44V V-............................................................................-44V to +0.3V V+ to V-...................................................................-0.3V to +44V CAL, LATCH A_, EN, NO_, COM_, REFHI,
REFLO (Note 1)................................(V- - 0.3V) to (V+ + 0.3V)Continuous Current (any terminal)....................................±30mA Peak Current, NO_ or COM_
(pulsed at 1ms, 10% duty cycle max).........................±100mA
Continuous Power Dissipation (T A = +70°C)
SSOP (derate 8mW/°C above +70°C)..........................640mW Wide SO (derate 8mW/°C above +70°C)......................800mW Plastic DIP (derate 10.53mW/°C above +70°C)...........842mW Operating Temperature Ranges
MAX4578C_P/MAX4579C_P................................0°C to +70°C MAX4578E_P/MAX4579E_P.............................-40°C to +85°C Storage Temperature Range.............................-65°C to +160°C Lead Temperature (soldering, 10sec).............................+300°C
Note 1:Signals on NO_, COM_, EN, LATCH, CAL, A_ exceeding V+ or V- are clamped by internal diodes. Limit forward current to
maximum current ratings.
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
_______________________________________________________________________________________3
ELECTRICAL CHARACTERISTICS—Dual ±15V Supplies (continued)
(V+ = +15V ±10%, V- = -15V ±10%, logic levels = 2.4V and 0.8V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.) (Note 2)
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 4_______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS—Dual ±15V Supplies (continued)
(V+ = +15V ±10%, V- = -15V ±10%, logic levels = 2.4V and 0.8V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.) (Note 2)
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
_______________________________________________________________________________________5
ELECTRICAL CHARACTERISTICS—Dual ±5V Supplies
(V+ = +5V ±10%, V- = -5V ±10%, logic levels = 2.4V and 0.8V,T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.) (Note 2)
ELECTRICAL CHARACTERISTICS—Dual ±15V Supplies (continued)
(V+ = +15V ±10%, V- = -15V ±10%, logic levels = 2.4V and 0.8V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.) (Note 2)
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 6_______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS—Dual ±5V Supplies (continued)
(V+ = +5V ±10%, V- = -5V ±10%, logic levels = 2.4V and 0.5V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T = +25°C.) (Note 2)
ELECTRICAL CHARACTERISTICS—Single +12V Supply
(V+ = +12V, V- = 0, logic levels = 2.4V and 0.8V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.) (Note 2)
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
_______________________________________________________________________________________7
Note 2:The algebraic convention, where the most negative value is a minimum and the most positive value a maximum, is used in
this data sheet.
Note 3:Guaranteed by design.
Note 4:?R ON = R ON(MAX)- R ON(MIN).
Note 5:Leakage parameters are 100% tested at maximum-rated hot temperature and guaranteed by correlation at T A = +25°C.
Note 6:If the logic inputs can float during power-on, connect a 1M ?pull-up from LATCH to V+. See Applications Information section.Note 7:Off-Isolation = 20log 10(V COM / V NO ), V COM = output, V NO = input to off switch.Note 8:Between any two switches.
Note 9:Leakage parameters testing at single supply are guaranteed by correlation with dual supplies.
ELECTRICAL CHARACTERISTICS—Single +12V Supply (continued)
(V+ = +12V, V- = 0, logic levels = 2.4V and 0.8V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.) (Note 2)
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 8_______________________________________________________________________________________
150
350250
550450650750-15
-10
-5
05
10
15
ON-RESISTANCE vs. V COM
(DUAL SUPPLIES)
V COM (V)
R O N (?)
050
100150200250300350400-15
-5
-10
05
10
15
ON-RESISTANCE vs. V COM AND TEMPERATURE (±15V DUAL SUPPLIES)
V COM (V)
R O N (?)
200100300
600700500400800
-5-3-2-10-412345
V COM (V)
R O N (?)
ON-RESISTANCE vs. V COM AND TEMPERATURE (±5V DUAL SUPPLIES)
300
7005001300110090019001700150021000
5.0
2.5
7.5
10
12.5
ON-RESISTANCE vs. V COM
(SINGLE SUPPLY)
V COM (V)
R O N (?)0.0001
0.010.00110.1100101000-55-155
-3525456585105125LEAKAGE CURRENT vs. TEMPERATURE
TEMPERATURE (°C)L E A K A G E C U R R E N T (n A )
400200800600
120010001400180016002000
1.0 1.5
2.00.5 2.5
3.0 3.5
4.54.0
5.0
ON-RESISTANCE vs. V COM AND TEMPERATURE (5V SINGLE SUPPLY)
V COM (V)
R O N (?)
0200100
400300600
5007000
4
62
8
10
12
V COM (V)
R O N (?)
ON-RESISTANCE vs. V COM AND TEMPERATURE (12V SINGLE SUPPLY)
1m 100μ10μ1μ100n
10n 1n
-4020406080-200100SUPPLY CURRENT vs. TEMPERATURE
TEMPERATURE (°C)I +, I - (A )
200100400300600500
70059711136108121415
TURN-ON/TURN-OFF TIME vs. SUPPLY
M A X 4578/79 T O C 09
V+, V- (V)
t O N , t O F F (n s )
t ON
t OFF
Typical Operating Characteristics
(T A = +25°C, unless otherwise noted.)
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
_______________________________________________________________________________________9
010050200150350300250400-40
-20
20
40
60
80
100TURN-ON/TURN-OFF
TIME vs. TEMPERATURE (±15V)
TEMPERATURE (°C)t O N , t O F F (n s )
200100400300800700500600900-400-2020406080100TURN-ON/TURN-OFF
TIME vs. TEMPERATURE (±5V)
TEMPERATURE (°C)t O N , t O F F (n s )
200100400300700600500800
-400-2020406080100
TURN-ON/TURN-OFF
TIME vs. TEMPERATURE (12V)
TEMPERATURE (°C)
t O N , t O F F (n s )
-40
-242±15V
±12V
±5V
8610-15
-5
0-10
5
1015CHARGE INJECTION vs. V COM
M A X 4578/79 t o c 13
V COM (V)
Q (p C )
4080.900
4080.9604080.9204080.9404081.0404081.0204081.0004080.9804081.0804081.0604081.10017935111315
28104
61214GAIN DIVIDER OUTPUT
vs. V REFHI
V REFHI (V)
O U T P U T R A T I O (L S B )
14.900
14.96014.92014.94015.04015.02015.00014.98015.08015.06015.10017935111315
2810461214
OFFSET DIVIDER OUTPUT
vs. V REFHI
V REFHI (V)
O U T P U T R A T I O (L S B )
14.900
14.96014.92014.94015.04015.02015.00014.98015.08015.06015.100
-40
080100
2060-20OFFSET DIVIDER OUTPUT vs. TEMPERATURE
TEMPERATURE (°C)
O U T P U T R A T I O (L S B )
4080.900
4080.9604080.9204080.9404081.0404081.0204081.0004080.9804081.0804081.0604081.100-4080
100
2060-200GAIN DIVIDER OUTPUT vs. TEMPERATURE
TEMPERATURE (°C)
O U T P U T R A T I O (L S B )
2060.00
2058.002056.002054.002052.002050.002048.002046.002044.002042.00
2040.00
5
7
8
9
6
101112141315(V+ / 2) DIVIDER OUTPUT vs. SUPPLY VOLTAGE
M A X 4578/79 t o c 18
V+, V- (V)
O U T P U T R A T I O (L S B )
Typical Operating Characteristics (continued)
(T A = +25°C, unless otherwise noted.)
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 10______________________________________________________________________________________
2055
2054205320522051205020492048204720462045
-40
-20
20
60
80
100
(V+ / 2) DIVIDER OUTPUT vs. TEMPERATURE
TEMPERATURE (°C)
O U T P U T R A T I O (L S B )
2545
2550
2555
2560
25652570
5
9
107
8
6
1112131415
(V+ - V-) DIVIDER OUTPUT vs. SUPPLY VOLTAGE
M A X 4578/79 t o c 20
V+, V- (V)
O U T P U T R A T I O (L S B )
2570
25682566256425622560255825562554
2552
-40
-20
20
60
80
100
(V+ - V-) DIVIDER OUTPUT vs. TEMPERATURE
TEMPERATURE (°C)
O U T P U T R A T I O (L S B )
250
300
400350
450
500
-40
-20
20
40
60
80
100
R OUT vs. TEMPERATURE
(OFFSET DIVIDER AND GAIN DIVIDER)
TEMPERATURE (°C)
R O U T (?)
4500
4700
4900550053005100
570059006100-40
-20
20
40
60
80
100
R OUT vs. TEMPERATURE
(V+ / 2 DIVIDER AND V+ - V- DIVIDER)
TEMPERATURE (°C)
R O U T (?)
0dB
100k
10M
100M
FREQUENCY RESPONSE
FREQUENCY (Hz)
10dB/div
40°/div
1M
Typical Operating Characteristics (continued)
(T A = +25°C, unless otherwise noted.)
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
______________________________________________________________________________________11
Pin Descriptions
MAX4578 (Single 8-to-1 Cal-Mux)
MAX4579 (Dual 4-to-1 Cal-Mux)
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 12______________________________________________________________________________________
MAX4578 (Single 8-to-1 Cal-Mux)
Truth Tables
MAX4579 (Dual 4-to-1 Cal-Mux)
x = Don’t Care
x = Don’t Care
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
______________________________________________________________________________________13
Detailed Description
The MAX4578/MAX4579 are multiplexers with addition-al calibration features. Internal resistor-dividers gener-ate accurate voltage ratios from an external voltage reference, allowing zero and full-scale calibration of ADC systems, as well as facilitation of system self-mon-itoring. To access the resistor-dividers, assert the CAL pin. When CAL and ENABLE are asserted, the three address pins select one of the various resistor-divider or external reference outputs. The MAX4578/ MAX4579also contain a LATCH input that allows the state of the CAL and address signals to be captured.
Calibration Functions
The gain-divider, offset-divider, REFHI, and REFLO modes allow calibration of offset and gain errors in ADC systems. The gain-divider mode outputs a voltage ratio that is 4081/4096 of V REFHI - V REFLO , accurate to 0.1/4096 or better than 15 bits. The offset-divider mode outputs a voltage ratio that is 15/4096 of V REFHI -V REFLO , also accurate to 0.1/4096. The REFHI mode allows the voltage on the REFHI pin to be switched to the output. The REFLO mode allows the voltage on the REFLO pin to be switched to the output.
Self-Monitoring Functions
The self-monitoring functions are intended to allow an ADC to measure its own supply voltage. The MAX4578has an internal divide-by-two resistor string between V+and GND that is accurate to 8 bits. It also has a 5/8resistor string between V+ and V- that is accurate to 8bits. This divider string allows measurement of the nega-tive supply with a unipolar ADC. GND can also be switched to the output, eliminating the need for an addi-tional multiplexer channel.
__________ Applications Information
The MAX4578/MAX4579’s construction is typical of most CMOS analog switches. There are three supply pins: V+, V-, and GND. The positive and negative power supplies provide drive to the internal CMOS switches and set the limits of the analog voltage on any switch. Reverse-biased ESD protection diodes are internally connected between each analog signal pin and both V+ and V-. If the voltage on any pin exceeds V+ or V-, one of these diodes will conduct. During nor-mal operation, these reverse-biased ESD diodes leak,forming the only current drawn from V-.
Virtually all the analog leakage current is through the ESD diodes. Although the ESD diodes on a given sig-nal pin are identical, and therefore fairly well balanced,
they are reverse-biased differently. Each is biased by either V+ or V- and the analog signal. This means their leakage varies as the signal varies. The difference in the two-diode leakage from the signal path to the V+and V- pins constitutes the analog signal-path leakage current. All analog-leakage current flows to the supply terminals, not to the other switch terminal, which explains how both sides of a given switch can show leakage cur-rents of either the same or opposite polarity.
There is no connection between the analog-signal paths and GND. The analog-signal paths consist of an N-channel and P-channel MOSFET with their sources and drains paralleled and their gates driven out of phase with 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 analog switch-es. This drive signal is the only connection between the logic supplies and the analog supplies. All pins have ESD protection to V+ and to V-.
Increasing V- has no effect on the logic-level thresh-olds, but it does increase the drive to the P-channel switches, which reduces their on-resistance. V- also sets the negative limit of the analog-signal voltage.
The logic-level thresholds are CMOS- and TTL-compatible when V+ is greater than +4.5V.
Bipolar-Supply Operation
The MAX4578/MAX4579 operate with bipolar supplies between ±4.5V and ±20V. The V+ and V- supplies need not be symmetrical, but their sum cannot exceed the absolute maximum rating of 44V. Note: Do not connect the MAX4578/MAX4579 V+ pin to +3V AND connect logic-level input pins to TTL logic-level signals. TTL logic-level outputs can exceed the absolute maximum ratings, which will cause damage to the part and/or external circuits.
Single-Supply Operation
The MAX4578/MAX4579 operate from a single supply between +4.5V and +36V when V- is connected to GND.All of the bipolar precautions must be observed (see Bipolar Supply Operation section). However these parts are optimized for ±15V operation, and most AC and DC characteristics are degraded significantly when depart-ing from ±15V. As the overall supply voltage (V+ to V-) is lowered, switching speed, on-resistance, off-isolation,and distortion will degrade, and supply current will decrease (see the Typical Operating Characteristics section).
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 14
______________________________________________________________________________________
Single-supply operation also limits signal levels and interferes with ground referenced signals. When V- = 0,AC signals are limited to -0.3V. Voltages below -0.3V can be clipped by the internal ESD-protection diodes,and the parts can be damaged if excessive current flows.
Power Up
During power up, on-chip latches will strobe whatever addresses are present if EN goes high before LATCH reaches a logic high. When this condition occurs, one of the internal dividers connected between the supplies may immediately turn on, causing higher supply current (1.4mA) when the enable input is toggled. Avoid this condition by ensuring that EN stays low until the remaining logic inputs are valid. To accomplish this,connect a resistor from EN to ground or apply a low voltage to EN before the other logic inputs go high.
Power Off
When power to the MAX4578/MAX4579 is off (i.e., V+ =V- = 0), the Absolute Maximum Ratings still apply. This means that neither logic-level inputs on NO_ nor sig-nals on COM_ can exceed ±0.3V. Voltages beyond ±0.3V cause the internal ESD-protection diodes to con-duct, and the parts can be damaged if excessive cur-rent flows.
______________________________________________Test Circuits/Timing Diagrams
Figure 1. Transition Time
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
______________________________________________________________________________________
15
Figure 2. Break-Before-Make Interval
Test Circuits/Timing Diagrams (continued)
Figure 3. Enable Switching Time
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 16______________________________________________________________________________________
Figure 4. Charge Injection
_________________________________Test Circuits/Timing Diagrams (continued)
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
______________________________________________________________________________________17
Figure 5. Off-Isolation/Crosstalk
_________________________________Test Circuits/Timing Diagrams (continued)
Figure 6. NO_/COM_ Capacitance
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 18______________________________________________________________________________________
Figure 7. Setup Time, Hold Time, Latch Pulse Width Figure 8. Enable Setup Time
_________________________________Test Circuits/Timing Diagrams (continued)
MAX4578/MAX4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers
______________________________________________________________________________________19
Pin Configurations/
Functional Diagrams (continued)
M A X 4578/M A X 4579
High-Voltage, Single 8-to-1/Dual 4-to-1 Cal-Multiplexers 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.
20____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600?1998 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
Ordering Information (continued)
Package Information
___________________Chip Information
TRANSISTOR COUNT: 520