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LTC1409

12-Bit, 800ksps Sampling

A/D Converter with Shutdown

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FEATURE

DESCRIPTIO

The LTC

µs, 800ksps, sampling 12-bit A/D

converter that draws only 80mW from

±5V supplies. This

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

and-hold and a precision reference. Two digitally selectable

power Shutdown modes provide flexibility for low power

systems.

The LTC1409 full-scale input range is

±2.5V. Maximum

DC specs include

±1LSB INL and ±1LSB DNL over tem-

perature. Outstanding AC performance includes 72.5dB

S/(N + D) at the Nyquist input frequency of 400kHz.

The unique differential input sample-and-hold can acquire

single-ended or differential input signals up to its 20MHz

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 a

µP compatible, 12-bit parallel output port.

There is no pipeline delay in the conversion results.

A separate convert start input and a data ready signal

(BUSY) ease connections to FIFOs, DSPs and micropro-

cessors. A digital output driver power supply pin allows

direct connection to 3V logic.

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Sample Rate: 800ksps

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Power Dissipation: 80mW

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72.5dB S/(N + D) and 86dB THD at Nyquist

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No Pipeline Delay

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Nap (4mW) and Sleep (10

µW) Shutdown Modes

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Operates with Internal 15ppm/

°C Reference

or External Reference

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True Differential Inputs Reject Common Mode Noise

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20MHz Full Power Bandwidth Sampling

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±2.5V Bipolar Input Range

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28-Pin SO Wide and SSOP Package

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APPLICATI

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Telecommunications

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Digital Signal Processing

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Multiplexed Data Acquisition Systems

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High Speed Data Acquisition

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Spectrum Analysis

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Imaging Systems

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

APPLICATI

TYPICAL

800kHz, 12-Bit Sampling A/D Converter

Effective Bits and Signal-to-(Noise + Distortion)

vs Input Frequency

1

2

3

4

5

6

7

8

9

10

11

12

13

14

28

27

26

25

24

23

22

21

20

19

18

17

16

15

REFCOMP

AGND

D11(MSB)

D10

D9

D8

D7

D6

D5

D4

DGND

BUSY

CS

CONVST

RD

SHDN

NAP/SLP

OGND

D0

D1

D2

D3

LTC1409

10

µF

DIFFERENTIAL

ANALOG INPUT

(–2.5V TO 2.5V)

2.50V

10

µF

10

µF

–5V

5V

12-BIT

PARALLEL

BUS

µP CONTROL

LINES

LTC1409 • TA01

INPUT FREQUENCY (Hz)

2

4

6

8

10

10k

100k

1M

10M

LTC1409 • TA02

0

1k

12

74

68

62

56

50

NYQUIST

FREQUENCY