Rainbow Electronics MAX1422 - Manual

General Description
The MAX1422 +3.3V, 12-bit analog-to-digital converter
(ADC) features a fully-differential input, pipelined, 12-
stage ADC architecture with wideband track-and-hold
(T/H) and digital error correction incorporating a fully-dif-
ferential signal path. The MAX1422 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
137mW while delivering a 67dB (typ) signal-to-noise
ratio (SNR) at a 5MHz input frequency and a 20Msps
sampling frequency. The fully-differential input stage
has a small signal -3dB bandwidth of 400MHz and may
be operated with single-ended inputs.
An internal +2.048V precision bandgap reference sets
the ADCs full-scale range. A flexible reference structure
accommodates an internally or externally applied
buffered or unbuffered reference for applications
requiring increased accuracy or a different input volt-
age range.
In addition to low operating power, the MAX1422 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
2mA (typ) supply current reduction. For idle periods, a
full shutdown mode is available to maximize power sav-
ings.
The MAX1422 provides parallel, offset binary, CMOS-
compatible three-state outputs.
The MAX1422 is available in a 7mm ✕ 7mm, 48-pin
TQFP package and is specified over the commercial
(0°C to +70°C) and extended industrial (-40°C to
+85°C) temperature ranges.
Pin-compatible higher-speed versions of the MAX1422
are also available. Please refer to the MAX1421 data
sheet for 40Msps and the MAX1420 data sheet for
60Msps.
________________________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
♦ Internal +2.048V Precision Bandgap Reference
♦ Differential Wideband Input T/H Amplifier
♦ Power-Down Modes
130mW (Reference Shutdown Mode)
10µW (Shutdown Mode)
♦ Space-Saving 48-Pin TQFP Package
MAX1422
12-Bit, 20Msps, +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
MAX1422
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
19-1899; Rev 0; 5/01
Ordering Information
PART TEMP. RANGE PIN-PACKAGE
MAX1422CCM 0 °C to +70°C 48 TQFP
MAX1422ECM -40 °C to +85°C 48 TQFP
Functional Diagram appears at end of data sheet.
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.