MAXIM MAX1421 12-Bit, 40Msps, 3.3V Low-Power ADC with Internal Reference

19-1900; Rev 1; 5/06

12-Bit, 40Msps, 3.3V, Low-Power ADC

with Internal Reference

General Description Features

The MAX1421 is a 3.3V, 12-bit analog-to-digital con- Single 3.3V Power Supply verter (ADC), featuring a fully-differential input,

67d B SNR at f IN = 5MHz

pipelined, 12-stage ADC architecture with wideband track-and-hold (T/H) and digital error correction incor-

66d B SNR at f IN = 15MHz

porating a fully-differential signal path. The MAX1421 is

Internal, 2.048V Precision Bandgap Reference

optimized for low-power, high-dynamic performance applications in imaging and digital communications.

Differential, Wideband Input T/H Amplifier

The converter operates from a single 3.3V supply, con-

suming only 188m W while delivering a typical signal-to- Power-Down Modes

noise ratio (SNR) of 66d B at an input frequency of 180m W (Reference Shutdown Mode) 15MHz and a sampling frequency of 40Msps. The fully- 10µW (Shutdown Mode) differential input stage has a small signal -3d B band-

Space-Saving 48-Pin TQFP Package

width of 400MHz and may be operated with single-ended inputs. An internal 2.048V precision bandgap reference sets the full-scale range of the ADC. A flexible reference Ordering Information structure accommodates an internal or externally

applied buffered or unbuffered reference for applica- PIN- PKG

PART* TEMP RANGE

PACKAGE CODE

tions requiring increased accuracy or a different input voltage range. M AX1421CCM 0°C to +70°C 48 TQFP C48-2 In addition to low operating power, the MAX1421 fea- M AX1421ECM -40°C to +85°C 48 TQFP C48-2

AG ND AG ND

tures two power-down modes, a reference power-down

AV DD AV DD M AX1421ECM+ -40°C to +85°C 48 TQFP C48-2

and a shutdown mode. In reference power-down, the AV CM

internal bandgap reference is deactivated, resulting in +Denotes lead-free package. AG ND RE FN

a typical 2m A supply current reduction. For idle peri- CL RE FP

ods, a full shutdown mode is available to maximize CL RE FI power savings. AG ND AV DD AV DD AG ND Pin Configuration

The MAX1421 provides parallel, offset binary, CMOS-

DV DD PD

compatible three-state outputs.

DG ND OE

The MAX1421 is available in a 7mm x 7mm, 48-pin D0 D1 TQFP package, and is specified over the commercial D1 D1 (0°C to +70°C) and the extended industrial (-40°C to +85°C) temperature ranges.

Pin-compatible higher- and lower-speed versions of the AGND D9 AVDD D8

MAX1421 are also available. Please refer to the

AVDD D7

MAX1420 data sheet for a frequency of 60Msps and

AGND D6

the MAX1422 data sheet for a frequency of 20Msps.

AGND DVDD

INP DVDD

________________________Applications MAX1421

INN DGND AGND DGND

Medical Ultrasound Imaging

AGND D5

CCD Pixel Processing

AVDD D4 AVDD D3

Data Acquisition

AGND D2

Radar IF and Baseband Digitization

Functional Diagram appears at end of data sheet. 48-TQFP

Maxim Integrated Products

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.