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LTC1406

Low Power, 8-Bit, 20Msps,

Sampling A/D Converter

The LTC

which draws only 150mW from a single 5V supply. This

easy-to-use device includes a high dynamic range sample-

and-hold with a 250MHz bandwidth.

The LTC1406’s full-scale input range is

±1V. The inputs

can be driven differentially or one input can be tied to a

fixed voltage and the other input driven with a

±1V bipolar

input. Maximum DC specifications include

±1LSB DNL

and INL over temperature. Outstanding AC performance

includes 48.5dB S/(N + D) and 62dB THD with a 1MHz

input; 47.5dB S/(N + D) and 59dB THD at the Nyquist input

frequency of 10MHz.

The unique differential input sample-and-hold can acquire

single-ended or differential input signals up to its 250MHz

bandwidth. The 60dB common mode rejection allows

users to eliminate ground loops and common mode noise

by measuring signals differentially from the source.

The ADC has an 8-bit parallel output port with separate

power supply and ground allowing easy interface to 3V

digital systems. The pipelined architecture has five clock

cycles of data latency.

FEATURES

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Low Power, 8-Bit, 20Msps ADC

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250MHz Internal Sample-and-Hold

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7 Effective Bits at 70MHz Input Frequency

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±1LSB DNL and INL Max

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Single 5V Supply and 150mW Dissipation

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Power Down to 1

µA

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True Differential Inputs Reject Common Mode Noise

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Accepts Single-Ended or Differential Input Signals

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±1V Differential or 2V Single-Ended Input Span

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24-Pin Narrow SSOP Package

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

Low Power, 20MHz, 8-Bit Sampling ADC

INPUT FREQUENCY (Hz)

2

4

6

100k

1M

10M

100M

1406 TA02

0

3

5

7

1

850

44

38

32

Effective Bits and Signal-to-Noise + Distortion

vs Input Frequency

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Telecommunications

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Wireless Communications

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Digital Cellular Telephones

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CCDs and Image Scanners

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Video Digitizing and Digital Television

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Digital Color Copiers

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High Speed Undersampling

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Personal Computer Video

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High Speed Data Acquisition

TRACK-AND-

HOLD AMP

DIGITAL

DATA

8-BIT

PIPELINE

ADC

2.5k

OGND

AGND

AGND

SHDN

1.95k

2.2V

OUTPUT

DRIVERS

OF/UF

D7

D6

D5

D4

D3

D2

D1

D0

1406 BD

CLOCK

CIRCUITRY

CLK

+

7

8

94

10

3

5

6

1

23

2

11

12

22

21

20

19

18

17

16

15

24

–

DGND