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MAX328CWE中文资料

General Description

The MAX328/MA329 are monolithic CMOS analog multi-plexers. The MAX328 is a single-ended, 1-of-8 device,and the MAX329 is a differential, 2-of-8 device.

Designed to provide the lowest possible on- and off-leakages, these multiplexers switch signals from high source impedance, providing the mux operates into a high-input-impedance op amp or A/D converter. The MAX328/MAX329 are pin-for-pin replacements for the popular DG508/DG509 in these applications.

Adding an external 40k ?resistor to each input makes the MAX328/MAX329 an excellent fault-tolerant multi-plexer. L ow leakage (less than 1pA at +25°C) and 2.5k ?on-resistance allow the circuit to sustain 110V AC faults indefinitely while maintaining an error of less than 40nV for normal signals (i.e., 1pA times 40k ?).The MAX328/MAX329 work equally well with a single supply of 10V to 30V or dual supplies of ±5V to ±18V.They also perform well with unbalanced combinations of supply voltage, such as +12V and -5V or +5V and -15V.L ow power dissipation (1.9mW with ±15V supplies)allows use in portable applications.

Applications

Control Systems Data Logging Systems Aircraft Heads-Up Displays Data-Acquisition Systems Signal Routing

Features

o Ultra-Low Off- and On-Leakage: 1pA Typ o Bidirectional Operation (Use as Mux or Demux)o TTL and CMOS Logic Compatibility

o Analog Signal Range Includes Power-Supply Rails o Switching Speeds Less Than 1.5μs o Pin Compatible with DG508/DG509 and MAX358/MAX359o Latchup Proof Construction

MAX328/MAX329

Ultra-Low Leakage Monolithic CMOS

Analog Multiplexers

________________________________________________________________Maxim Integrated Products 1

Pin Configurations

Ordering Information

Typical Operating Circuit

19-1006; Rev 2; 9/01

For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at https://www.wendangku.net/doc/fb3200984.html,.

**Contact factory for availability. Substrate may be allowed to float or be connected to V+.

Ordering Information and Pin Configurations continued at end of data sheet.

M A X 328/M A X 329

Ultra-Low Leakage Monolithic CMOS Analog Multiplexers

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

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 V-V+........................................................................................+44V GND.....................................................................................+25V Digital Inputs (Note 1), V S , V D ............................-2V to (V+ + 2V)Current (Any Terminal, Except S or D)................................30mA Continuous Current, S or D

(pulsed at 1ms, 10% duty cycle max)............................40mA

Operating Temperature Range

MAX328/329 C _ _..............................................0°C to +70°C MAX328/329 E _ _...........................................-40°C to +85°C MAX328/329 M _ _.........................................-55°C to +125°C Power Dissipation (Package) (Note 1)

16-Pin CERDIP (Note 2)...............................................900mW 16-Pin Plastic DIP (Note 3)...........................................470mW 16-Pin Wide SO (Note 4)..............................................750mW 16-Pin QFN (Note 5)...................................................1538mw Storage Temperature.........................................-65°C to +150°C

Note 1:All leads soldered or welded to PC board.Note 2:Derate 12mW/°C above +75°C.Note 3:Derate 6.3mW/°C above +75°C.Note 4:Derate 10mW/°C above +75°C.Note 5:Derate 19.2mW/°C above +75°C.

MAX328/MAX329

Ultra-Low Leakage Monolithic CMOS

Analog Multiplexers

_______________________________________________________________________________________3

ELECTRICAL CHARACTERISTICS (continued)

(V+ = +15V, V- = -15V, GND = 0V, T A = +25°C, unless otherwise noted.)

teed by correlation at +25°C.

Note 7:Electrical characteristics, such as On-Resistance, change when power supplies other than ±15V are used. Power-supply

range is a design characteristic, not production tested.

Note 8:Guaranteed by design.

Typical values are for DESIGN AID ONLY, not guaranteed or subject to production testing.

M A X 328/M A X 329

Ultra-Low Leakage Monolithic CMOS Analog Multiplexers 4_______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (Over Temperature)

(V+ = +15V, V- = -15V, GND = 0V, T A = T MIN to T MAX , unless otherwise noted.)

MAX328/MAX329

Ultra-Low Leakage Monolithic CMOS

Analog Multiplexers

_______________________________________________________________________________________5

Typical Operating Characteristics

(T A = +25°C, unless otherwise noted.)

R DS(ON) vs. ANALOG INPUT FOR DUAL SUPPLIES

ANALOG INPUT (V)

R D S (O N ) (k ?)

-5

-10

1234567

890-15

R DS(ON) vs. ANALOG INPUT FOR SINGLE SUPPLY

ANALOG INPUT (V)

R D S (O N ) (k ?)

I S(OFF) vs. TEMPERATURE

TEMPERATURE (°C)

L E A K A G E (n A )

105856545255-15-350.0010.010.11.010.00.0001

-55125

I D(ON), I D(OFF)

vs. TEMPERATURE

TEMPERATURE (°C)

L E A K A G E (n A )

1058565

-15

-350.010.1

1.0101000.001

-55125

M A X 328/M A X 329

Ultra-Low Leakage Monolithic CMOS Analog Multiplexers 6_______________________________________________________________________________________

Truth Table—MAX328

Truth Table —MAX329

Note:Logic “0” = V AL ≤0.8V, Logic “1” = V AH ≥2.4V

MAX328/MAX329

Ultra-Low Leakage Monolithic CMOS

Analog Multiplexers

_______________________________________________________________________________________

Figure 2. Break-Before-Make Delay (t OPEN )

Figure 3. Enable Delay (t ON(EN)OFF(EN)

M A X 328/M A X 329

Ultra-Low Leakage Monolithic CMOS Analog Multiplexers 8

_______________________________________________________________________________________

Applications Information

Figure 4 is a typical circuit for converting the MAX328/MAX329 into a fault-tolerant mux. In this application, the internal diodes limit the voltage at the MAX328 input to ±15.7V (±15V supplies). No external diodes need to be added with the MAX328/MAX329,unlike conventional multiplexers requiring external diodes.

The resistors, R, need to be 39k ?or higher to limit the power dissipation in the resistor when a 120V AC fault occurs (i.e., power dissipation is (120-16)2/39k ?or 0.28W. This is why a 1/2/W resistor is needed). The circuit withstands an indefinite fault to a 120V AC line with no damage to any component.

In addition to allowing fault-protection, the guaranteed low leakage of the MAX328/MAX329 also reduces signal errors. The circuit in Figure 4 produces an error voltage of 10pA (max leakage) x 39k ?or 0.39μV at room tempera-ture and 39μV at +125°C. Therefore, for 10V signals, the MAX328/MAX329 allows 17-bit resolution (38μV = 1LSB)over the full temperature range.

S8D 9

111213

S6S5V+

GND

543

S4S3S2S1V-

151612A2

A1A0

0.104”(2.64mm)0.118”(2.90mm)

A1211676543

S4A S3A S2A S1A V-

DB DA 9

1011121314

S4B

S3B

S2B S1B V+

GND

MAX328

MAX329

Chip Topographies

Figure 4.Fault-Tolerant MUX (indefinitely withstands 120V AC

fault voltages)

MAX328/MAX329

Ultra-Low Leakage Monolithic CMOS

Analog 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.

Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________9?2001 Maxim Integrated Products

Printed USA

is a registered trademark of Maxim Integrated Products.

Ordering Information (continued)

**Contact factory for availability. Substrate may be allowed to float or be connected to V+.

Pin Configurations (continued)

Package Information

For the latest package outline information, go to https://www.wendangku.net/doc/fb3200984.html,/packages .