Rainbow Electronics MAX1121 User Manual
General description, Applications, Features
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General Description
The MAX1121 is a monolithic 8-bit, 250Msps analog-to-
digital converter (ADC) optimized for outstanding
dynamic performance at high IF frequencies up to
500MHz. The product operates with conversion rates of
up to 250Msps while consuming only 477mW.
At 250Msps and an input frequency of 100MHz, the
MAX1121 achieves a spurious-free dynamic range
(SFDR) of 68dBc. Its excellent signal-to-noise ratio
(SNR) of 48.9dB at 10MHz remains flat (within 0.5dB)
for input tones up to 500MHz. This makes the MAX1121
ideal for wideband applications such as digital predis-
tortion in cellular base-station transceiver systems.
The MAX1121 requires a single 1.8V supply. The ana-
log input is designed for either differential or single-
ended operation and can be AC- or DC-coupled. The
ADC also features a selectable on-chip divide-by-2
clock circuit, which allows the user to apply clock fre-
quencies as high as 500MHz. This helps to reduce the
phase noise of the input clock source. A differential
LVDS sampling clock is recommended for best perfor-
mance. The converter’s digital outputs are LVDS com-
patible, and the data format can be selected to be
either two’s complement or offset binary.
The MAX1121 is available in a 68-pin QFN with
exposed paddle (EP) and is specified over the industri-
al (-40°C to +85°C) temperature range.
For pin-compatible, higher resolution versions of the
MAX1121, refer to the MAX1122 (170Msps), the
MAX1123 (210Msps), and the MAX1124 (250Msps)
data sheets.
Applications
Wireless and Wired Broadband Communication
Digital Oscilloscopes
Digital Predistortion Receivers
Communications Test Equipment
Radar and Satellite Subsystems Antenna Array
Processing
Instrumentation
Features
♦ 250Msps Conversion Rate
♦ SNR = 48.8dB/48.7dB at f
IN
= 100MHz/500MHz
♦ SFDR = 68dBc/63.8dBc at f
IN
= 100MHz/500MHz
♦ Single 1.8V Supply
♦ 477mW Power Dissipation at 250Msps
♦ On-Chip Track-and-Hold and Internal Reference
♦ On-Chip Selectable Divide-by-2 Clock Input
♦ LVDS Digital Outputs with Data Clock Output
♦ Evaluation Kit Available (Order MAX1124EVKIT)
MAX1121
1.8V, 8-Bit, 250Msps Analog-to-Digital Converter
with LVDS Outputs for Wideband Applications
________________________________________________________________
Maxim Integrated Products
1
58
59
60
61
62
54
55
56
57
63
38
39
40
41
42
43
44
45
46
47
AV
CC
AGND
AV
CC
TOP VIEW
AV
CC
OGND
OV
CC
ORP
ORN
D7P
D7N
D6P
D6N
52
53
D5P
D5N
AGND
AGND
AV
CC
CLKN
CLKP
AV
CC
AGND
OV
CC
OGND
N.C.
OV
CC
N.C.
N.C.
N.C.
D2P
D2N
OGND
OV
CC
DCLKP
DCLKN
OV
CC
D1P
D1N
D0P
35
36
37
D0N
N.C.
N.C.
AGND
INN
INP
AGND
AV
CC
AGND
AGND
AV
CC
AV
CC
AV
CC
AGND
REFADJ
REFIO
AGND
48
D3N
AV
CC
64
AGND
65
66
67
AGND
AGND
AV
CC
68
T/B
23
22
21
20
19
27
26
25
24
18
29
28
32
31
30
N.C.
N.C.
34
33
49
50
D4N
D3P
51
D4P
11
10
9
8
7
6
5
4
3
2
16
15
14
13
12
1
CLKDIV 17
MAX1121
EP
Pin Configuration
Ordering Information
19-3077; Rev 1; 2/04
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.
PART
TEMP RANGE
PIN-PACKAGE
MAX1121EGK
-40
°
C to +85
°
C
68 QFN-EP*
*EP = Exposed paddle.