Rainbow Electronics MAX1421 - Manual

General Description
The MAX1421 is a +3.3V, 12-bit analog-to-digital con-
verter (ADC), featuring a fully-differential input,
pipelined, 12-stage ADC architecture with wideband
track-and-hold (T/H) and digital error correction incor-
porating a fully-differential signal path. The MAX1421 is
optimized for low-power, high-dynamic performance
applications in imaging and digital communications.
The converter operates from a single +3.3V supply,
consuming only 188mW while delivering a typical sig-
nal-to-noise ratio (SNR) of 66dB at an input frequency
of 15MHz and a sampling frequency of 40Msps. The
fully-differential input stage has a small signal -3dB
bandwidth of 400MHz and may be operated with sin-
gle-ended inputs.
An internal +2.048V precision bandgap reference sets
the full-scale range of the ADC. A flexible reference
structure accommodates an internal or externally
applied buffered or unbuffered reference for applica-
tions requiring increased accuracy or a different input
voltage range.
In addition to low operating power, the MAX1421 fea-
tures two power-down modes, a reference power-down
and a shutdown mode. In reference power-down, the
internal bandgap reference is deactivated, resulting in
a typical 2mA supply current reduction. For idle peri-
ods, a full shutdown mode is available to maximize
power savings.
The MAX1421 provides parallel, offset binary, CMOS-
compatible three-state outputs.
The MAX1421 is available in a 7mm x 7mm, 48-pin
TQFP package, and is specified over the commercial
(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
MAX1421 are also available. Please refer to the
MAX1420 data sheet for a frequency of 60Msps and
the MAX1422 data sheet for a frequency of 20Msps.
________________________Applications
Medical Ultrasound Imaging
CCD Pixel Processing
Data Acquisition
Radar
IF and Baseband Digitization
Features
♦ Single +3.3V Power Supply
♦ 67dB SNR at f
IN = 5MHz
♦ 66dB SNR at f
IN = 15MHz
♦ Internal, +2.048V Precision Bandgap Reference
♦ Differential, Wideband Input T/H Amplifier
♦ Power-Down Modes
180mW (Reference Shutdown Mode)
10µW (Shutdown Mode)
♦ Space-Saving 48-Pin TQFP Package
MAX1421
12-Bit, 40Msps, +3.3V, Low-Power ADC
with Internal Reference
________________________________________________________________ Maxim Integrated Products 1
D9
D8
D7
D6
DV DD
DV DD
DGND
DGND
D5
D4
D3
D2
AGND
AV DD
AV DD
AGND
AGND
INP
INN
AGND
AGND
AV DD
AV DD
AGND
1
2
3
4
5
6
7
8
9
10
11
12
36
35
34
33
32
31
30
29
28
27
26
25
48-TQFP
MAX1421
AGND AV
DD
AV
DD
AGND
CLK CLK
AGND AV
DD
DV
DD
DGND
D0 D1
13 14 15 16 17 18 19 20 21 22 23 24
48 47 46 45 44 43 42 41 40 39 38 37
AGND AV
DD
CML REFN REFP REFIN AV
DD
AGND PD OE D11 D10
Pin Configuration
19-1900; Rev 0; 5/01
Ordering Information
48 TQFP
PIN-PACKAGE TEMP. RANGE
0°C to +70°C MAX1421CCM
PART
Functional Diagram appears at end of data sheet.
48 TQFP -40°C to +85°C MAX1421ECM
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.