MAX105 Datasheet, PDF (12/21 Pages) Maxim Integrated Products – Dual, 6-Bit, 800Msps ADC with On-Chip, Wideband Input Amplifier

Dual, 6-Bit, 800Msps ADC with On-Chip,
Wideband Input Amplifier
DREADY+/DREADY-
INI+
PRE-AMP
INI-
2kΩ
CM BUFFER
MAX105
I ADC
REF
PRIMARY
DATA PORT
P0I-P5I
AUXILIARY
DATA PORT
A0I-A5I
AV_CC
1:2
10kΩ
REFERENCE
2kΩ
CM BUFFER
INQ+
PRE-AMP
INQ-
REF
Q ADC
REF
DOR
DOR+/DOR-
PRIMARY
DATA PORT
P0Q-P5Q
AUXILIARY
DATA PORT
A0Q-A5Q
10kΩ
P0I+/P0I-
P5I+/P5I-
A0I+/A0I-
A5I+/A5I-
CLK+
CLK-
P0Q+/P0Q-
P5Q+/P5Q-
A0Q+/A0Q-
A5Q+/A5Q-
Figure 1. MAX105 Flash Converter Architecture
signal-to-noise ratio (SNR) specifications will degrade.
The MAX105’s on-board, wide-bandwidth input ampli-
fiers (I&Q) reduce this effect significantly, allowing pre-
cise digitizing of fast analog data at high conversion
rates. The input amplifiers buffer the input signal and
allow a full-scale signal input range of ±400mV
(800mV_p-p).
Internal Reference
The MAX105 features an integrated, buffered +2.5V
precision bandgap reference. This reference is internal-
ly scaled to match the analog input range specification
of ±400mV. The data converter’s reference output
(REF) can source up to 500µA. REF should be buffered,
if used to supply external devices.
LVDS Digital Outputs
The MAX105 provides data in two’s complement format
to differential LVDS outputs. A simplified circuit
schematic of the LVDS output cells is shown in Figure
2. All LVDS outputs are powered from separate I-chan-
nel OV_CCI and Q-channel OV_CCQ (Q-channel) power
supplies, which may be operated at +3.3V ±10%. The
OV_CCI
OV_CCI
P0I+ - P5I+
A0I+ - A5I+
55Ω
55Ω
OV_CCI
P0I- - P5I-
A0I- - A5I-
MAX105
Figure 2. Simplified LVDS Output Model
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