REV. B

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reliable. However, no responsibility is assumed by Analog Devices for its

use, nor for any infringements of patents or other rights of third parties that

may result from its use. No license is granted by implication or otherwise

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a

AD7676

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700

www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 2002

16-Bit,

1 LSB INL,

500 kSPS, Differential ADC

FUNCTIONAL BLOCK DIAGRAM

CONTROL LOGIC AND

CALIBRATION CIRCUITRY

CLOCK

OB/

2C

16

D[15:0]

BUSY

CS

SER/

PAR

OGND

OVDD

DGND

DVDD

SERIAL

PORT

PARALLEL

INTERFACE

BYTESWAP

RD

AVDD AGND

REF REFGND

PD

RESET

CNVST

IN–

SWITCHED

CAP DAC

AD7676

IN+

Table I. PulSAR Selection

Type/kSPS

100–250

500–570

800–1000

Pseudo Differential

AD7660

AD7650

AD7664

True Bipolar

AD7663

AD7665

AD7671

True Differential

AD7675

AD7676

AD7677

18-Bit

AD7678

AD7679

AD7674

Simultaneous/

AD7654

Multichannel

FEATURES

Throughput: 500 kSPS

INL:

1 LSB Max ( 0.0015% of Full Scale)

16-Bit Resolution with No Missing Codes

S/(N+D): 94 dB Typ @ 45 kHz

THD: –110 dB Typ @ 45 kHz

Differential Input Range:

2.5 V

Both AC and DC Specifications

No Pipeline Delay

Parallel (8 Bits/16 Bits) and Serial 5 V/3 V Interface

SPI™/QSPI™/MICROWIRE™/DSP Compatible

Single 5 V Supply Operation

67 mW Typical Power Dissipation, 15

W @ 100 SPS

Power-Down Mode: 7

W Max

Packages: 48-Lead Quad Flatpack (LQFP)

48-Lead Frame Chip Scale (LFCSP)

Pin-to-Pin Compatible with the AD7675

APPLICATIONS

CT Scanners

Data Acquisition

Instrumentation

Spectrum Analysis

Medical Instruments

Battery-Powered Systems

Process Control

GENERAL DESCRIPTION

The AD7676 is a 16-bit, 500 kSPS, charge redistribution SAR,

fully differential analog-to-digital converter (ADC) that oper-

ates from a single 5 V power supply. The part contains a high

speed 16-bit sampling ADC, an internal conversion clock,

error correction circuits, and both serial and parallel system

interface ports.

The AD7676 is hardware factory-calibrated and is comprehen-

sively tested to ensure such ac parameters as signal-to-noise ratio

(SNR) and total harmonic distortion (THD), in addition to the

more traditional dc parameters of gain, offset, and linearity.

It is fabricated using Analog Devices’ high performance, 0.6 micron

CMOS process and is available in a 48-lead LQFP or a tiny

48-lead LFCSP with operation specified from –40

°C to +85°C.

PRODUCT HIGHLIGHTS

1. Excellent INL

The AD7676 has a maximum integral nonlinearity of 1.0 LSB

with no missing 16-bit code.

2. Superior AC Performances

The AD7676 has a minimum dynamic of 92 dB, 94 dB typical.

3. Fast Throughput

The AD7676 is a 500 kSPS, charge redistribution, 16-bit

SAR ADC with internal error correction circuitry.

4. Single-Supply Operation

The AD7676 operates from a single 5 V supply and typically

dissipates only 67 mW. It consumes 7

µW maximum when in

power-down.

5. Serial or Parallel Interface

Versatile parallel (8 bits or 16 bits) or 2-wire serial interface

arrangement compatible with either 3 V or 5 V logic.

SPI and QSPI are trademarks of Motorola, Inc.

MIRCOWIRE is a trademark of National Semiconductor Corporation.