12-Bit, 10MHz Sampling

ANALOG-TO-DIGITAL CONVERTER

FEATURES

q HIGH SFDR: 80dB at NYQUIST

q HIGH SNR: 69dB

q LOW POWER: 180mW

q LOW DLE:

q FLEXIBLE INPUT RANGE

q OVERRANGE INDICATOR

APPLICATIONS

q IF AND BASEBAND DIGITIZATION

q CCD IMAGING

q SCANNERS

q TEST INSTRUMENTATION

DESCRIPTION

The ADS804 is a high-speed, high dynamic range, 12-bit,

pipelined Analog-to-Digital (A/D) converter. This converter

includes a high-bandwidth track-and-hold that gives excel-

lent spurious performance up to and beyond the Nyquist

rate. This high-bandwidth, linear track-and-hold minimizes

harmonics and has low jitter, leading to excellent SNR

performance. The ADS804 is also pin-compatible with the

5MHz ADS803 and the 20MHz ADS805.

The ADS804 provides an internal reference and can be

programmed for a 2Vp-p input range for the best spurious

performance and ease of driving. Alternatively, the 5Vp-p

input range can be used for the lowest input referred noise

of 0.09LSBs rms giving superior imaging performance. There

is also a capability to set the input range in between the 2Vp-

p and 5Vp-p input ranges or to use external reference. The

ADS804 also provides an over-range indicator flag to indi-

cate an input range that exceeds the full-scale input range of

the converter. This flag can be used to reduce the gain of the

front end gain-ranging circuitry.

The ADS804 employs digital error correction techniques to

provide excellent differential linearity for demanding imaging

applications. Its low distortion and high SNR give the extra

margin needed for communications, medical imaging, video,

and test instrumentation applications. The ADS804 is avail-

able in a SSOP-28 package.

12-Bit

Pipelined

A/D Converter Core

Reference and

Mode Select

Reference Ladder

and Driver

Timing Circuitry

Error

Correction

Logic

3-State

Outputs

T&H

D0

D11

•

•

•

CLK

+V

S

ADS804

VDRV

OE

SEL

REFB

V

REF

REFT

IN

V

IN

IN

(Opt.)

CM

OVR

ADS804

SBAS068B – JANUARY 1997 – REVISED AUGUST 2002

www.ti.com

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

Copyright © 1997, Texas Instruments Incorporated

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

ADS804E