Datasheet

MAX2037
Ultrasound Variable-Gain Amplifier
_______________________________________________________________________________________ 3
AC ELECTRICAL CHARACTERISTICS
(Figure 2, V
CC
= V
REF
= 4.75V to 5.25V, V
CM
= (3/5)V
REF
, T
A
= 0°C to +70°C, V
GND
= 0, PD = 0, VG_CLAMP_MODE = 1, f
RF
=
5MHz, capacitance to GND at each of the VGA differential outputs is 60pF, differential capacitance across the VGA outputs is 10pF,
R
L
= 1kΩ. Typical values are at V
CC
= V
REF
= 5V, T
A
= +25°C, unless otherwise noted.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Differential output
capacitance is 10pF,
capacitance to GND at
each single-ended
output is 60pF, R
L
= 1kΩ
18
Full-Scale Bandwidth f
-1.3dB
V
OUT
= 1.5V
P-P
,
3dB bandwidth,
gain = 10dB
No capacitive load
R
L
= 1kΩ
29
MHz
Small Signal Bandwidth f
-1.3dB
V
OUT
= 1.5mV
P-P
, 3dB bandwidth,
gain = 10dB
30 MHz
Differential Input Resistance R
IN
170 200 230 Ω
Input Effective Capacitance C
IN
f
RF
= 10MHz, each input to ground 15 pF
Differential Output Resistance R
OUT
100 Ω
Maximum Gain +29.5 dB
Minimum Gain -12.5 dB
Gain Range 42 dB
Absolute Gain Error
T
A
= +25°C, full gain range 0% to 100%,
V
REF
= 5V
±0.25 ±1.5 dB
VGA Gain Response Time 40dB gain change to within 1dB final value 1 µs
Input-Referred Noise
VG_CTL set for maximum gain,
no input signal
2 nV/√Hz
No input signal 22
Output-Referred Noise
VG_CTL set for
+10dB of gain
V
OUT
= 1.5V
P-P
,
1kHz offset
55
nV/√Hz
VG_CLAMP_MODE = 1,
VG_CTL set for +10dB of gain,
f
RF
= 5MHz, V
OUT
= 1.5V
P-P
-70
Second Harmonic HD2
VG_CLAMP_MODE = 1,
VG_CTL set for +10dB of gain,
f
RF
= 10MHz, V
OUT
= 1.5V
P-P
-55 -65
dBc
Third-Order Intermodulation
Distortion
IMD3
VG_CLT set for +10dB of gain, f
RF1
= 5MHz,
f
RF2
= 5.01MHz, V
OUT
= 1.5V
P-P
, V
REF
= 5V
(Note 4)
-40 -52 dBc