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LTC1391

8-Channel

Analog Multiplexer with

Cascadable Serial Interface

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Single 2.7V to

±5V Supply Operation

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Analog Inputs May Extend to Supply Rails

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Low Charge Injection

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Serial Digital Interface

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Low Leakage:

±5nA Max

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Guaranteed Break-Before-Make

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TTL/CMOS Compatible for All Digital Inputs

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Cascadable to Allow Additional Channels

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Can Be Used as a Demultiplexer

FEATURES

The LTC

multiplexer. It features a serial digital interface that allows

several LTC1391s to be daisy-chained together, increas-

ing the number of MUX channels available using a single

digital port.

switch leakage of 50pA and guaranteed break-before-

make operation. Charge injection is

±10pC maximum. All

digital inputs are TTL and CMOS compatible when oper-

ated from single or dual supplies. The inputs can with-

stand 100mA fault current.

The LTC1391 is available in 16-pin PDIP, SSOP and

narrow SO packages. For applications requiring 2-way

serial data transmission, see the LTC1390 data sheet.

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Data Acquisition Systems

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Communication Systems

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Signal Multiplexing/Demultiplexing

, LTC and LT are registered trademarks of Linear Technology Corporation.

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16

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12

11

10

9

S0

S1

S2

S3

S4

S5

S6

S7

D

CS

CLK

GND

ANALOG

INPUTS

LTC1391

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2

3

4

8

7

6

5

CLK

CS/SHDN

+IN

–IN

GND

LTC1285

3V

0.1

µF OPTIONAL A/D

INPUT FILTER

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µF

DATA IN

CLK

CS

DATA OUT

SERIAL INTERFACE

TO MUX AND ADC

1391 TA01

ANALOG INPUT VOLTAGE (V)

–5 –4

–2

0

2

4

300

250

200

150

100

50

0

–3

–1

1

3

1391 TA02

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On-Resistance vs

Analog Input Voltage

3V, 8-Channel 12-Bit ADC