Datasheet

MAX2078
Octal-Channel Ultrasound Front-End
with CW Doppler Mixers
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GAIN vs. DIFFERENTIAL ANALOG
CONTROL VOLTAGE
MAX2078 toc01
CONTROL VOLTAGE (V)
GAIN (dB)
210-1-2
15
25
35
45
5
-3 3
COMPLEX INPUT IMPEDANCE MAGNITUDE
vs. FREQUENCY
MAX2078 toc02
FREQUENCY (MHz)
INPUT IMPEDANCE (Ω)
15105
200
400
600
800
1000
0
020
1k
Ω
100
Ω
200
Ω
50
Ω
GAIN ERROR HISTOGRAM
MAX2078 toc03
GAIN ERROR (dB)
% UNITS
5
10
15
20
25
0
-0.175 -0.125 -0.075 -0.025
0.025 0.075 0.125 0.175 0.225 0.275
GAIN = 20dB
OUTPUT-REFERRED NOISE vs. GAIN
MAX2078 toc04
GAIN (dB)
NOISE (nV/√Hz)
352617
30
60
90
120
150
180
0
8
44
INPUT-REFERRED NOISE vs. GAIN
MAX2078 toc05
GAIN (dB)
352617
2
3
4
5
6
1
8
44
NOISE (nV/√Hz)
SECOND-HARMONIC DISTORTION
vs. GAIN
MAX2078 toc06
GAIN (dB)
HD2 (dBc)
383226
-80
-70
-60
-50
-40
-30
-90
20 44
V
OUT
= 1V
P-P
f
RF
= 10MHz
f
RF
= 2MHz
f
RF
= 5MHz
Typical Operating Characteristics
( Typical Application Circuit , V
REF
= 2.475V to 2.525V, V
CC1
= 3.13V to 3.47V, V
CC2
= 4.5V to 5.25V, T
A
= 0°C to +70°C, V
GND
= 0V,
NP = 0, PD = 0, CLP = 0, D43/D42/D41/D40 = 1/0/1/0 (R
IN
= 200Ω, LNA gain = 18.5dB), D45/D44 = 1/1 (f
C
= 18MHz), f
RF
= f
LO
/16
= 5MHz, capacitance to GND at each of the VGA differential outputs is 25pF, differential capacitance across VGA outputs is 15pF,
R
L
= 1kΩ differential, R
S
= 200Ω, CI_, CQ_ pulled up to 11V through four separate 0.1% 162Ω resistors, the rise/fall time of the LVDS
clock driving the LO_ is required to be 0.5ns, reference noise less than 10nV/√Hz from 1kHz to 20MHz, DOUT loaded with 10MΩ
and 60pF. Typical values are at V
CC1
= 3.3V, V
CC2
= 5V, T
A
= +25°C, unless otherwise noted.)
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