Precision, 16-Channel/Dual 8-Channel,

Low-Voltage, CMOS Analog Multiplexers

_______________________________________________________________________________________

7

______________________________________________________________Pin Description

—

PIN

MAX396

MAX397

NAME

FUNCTION

1

V+

Positive Supply-Voltage Input

2, 3, 13

1

N.C.

No Internal Connection

—

2

COMB

Analog Signal B Output* (bidirectional)

—

3, 13, 14

N.C.

No Internal Connection

4–11

—

NO16–NO9

Analog Signal Inputs* (bidirectional)

—

4–11

NO8B–NO1B

Analog Signal B Inputs* (bidirectional)

12

12

GND

Logic Ground

14–17

—

A3–A0

Logic Address Inputs

—

15, 16, 17

A2, A1, A0

Logic Address Inputs

18

18

EN

Logic Enable Input

19–26

—

NO1–NO8

Analog Signal Inputs* (bidirectional)

—

19–26

NO1A–NO8A

Analog Signal A Inputs* (bidirectional)

27

27

V-

Negative Supply-Voltage Input

28

—

COM

Analog Signal Output* (bidirectional)

—

28

COMA

Analog Signal A Output* (bidirectional)

__________Applications Information

Operation with Supply Voltages

Other than ±5V

Using supply voltages less than ±5V reduces the analog

signal range. The MAX396/MAX397 multiplexers (muxes)

operate with ±3V to ±8V bipolar supplies or with a +3V to

+15V single supply. Connect V- to GND when operating

with a single supply. Both devices can also operate with

unbalanced supplies, such as +10V and -5V. The

Typical

Operating Characteristics graphs show typical on-

resistance with ±3V, ±5V, +3V, and +5V supplies.

(Switching times increase by a factor of two or more for

operation at 5V or below.)

These muxes operate with a single supply as low as 1V,

although on-resistance and switching times become

extremely high. Performance is not guaranteed below

2.7V. This is useful information only because it assures

proper switch state while power supplies ramp up or

down slowly.

Overvoltage Protection

Proper power-supply sequencing is recommended for

all CMOS devices. Do not exceed the absolute maxi-

mum ratings, because stresses beyond the listed rat-

ings can cause permanent damage to the devices.

Always sequence V+ on first, then V-, followed by the

logic inputs, NO, or COM. If power-supply sequencing

is not possible, add two small-signal diodes (D1, D2) in

series with supply pins for overvoltage protection

(Figure 1). Adding diodes reduces the analog-signal

range to one diode drop below V+ and one diode drop

above V-, but does not affect the devices’ low switch

resistance and low leakage characteristics. Device

operation is unchanged, and the difference between

V+ and V- should not exceed 17V. These protection

diodes are not recommended when using a single supply.

*Analog signal inputs and outputs are names of convenience only; they are identical and interchangeable.

COM

V-

V+

NO

*INTERNAL PROTECTION DIODES

D2

D1

-5V

+5V

MAX396

MAX397

*

*

*

*

Figure 1. Overvoltage Protection Using External Blocking Diodes