MAX2038CCQ+ Maxim Integrated Products, MAX2038CCQ+ Datasheet - Page 15

• Manufacturer Part Number: MAX2038CCQ+
• Description: IC VGA W/OCTAL MIXER 8CH 100TQFP
• Manufacturer: Maxim Integrated Products
• Type: Variable Gain Amplifierr

Specifications of MAX2038CCQ+

• Applications: Medical Ultrasound Imaging, Sonar
• Mounting Type: Surface Mount
• Package / Case: 100-TQFP Exposed Pad, 100-eTQFP, 100-HTQFP, 100-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

A clamp is provided to limit the VGA output signals to
avoid overdriving the ADC or to prevent ADC satura-
tion. Set VG_CLAMP_MODE low to clamp the VGA dif-
ferential outputs at 2.4V
high to disable the clamp.
The device can also be powered down with PD. Set PD
to logic-high for power-down mode. In power-down
mode, the device draws a total supply current of 27mA.
Set PD to a logic-low for normal operation.
The device is also optimized for quick overload recovery
for operation under the large input-signal conditions that
are typically found in ultrasound input buffer imaging
applications. See the Typical Operating Characteristics
for an illustration of the rapid recovery time from a trans-
mit-related overload.
LO_LVDS+
LO_LVDS-
CWIN8
CWIN2
CWIN1
LOAD
• •
•
CLK
DIN
______________________________________________________________________________________
P-P
. Set the VG_CLAMP_MODE
CHANNEL 1
SELECTOR
5
DIVIDER
PHASE
CW_M1
5-BIT
Overload Recovery
SR
I Q
I/Q
V
CC
• •
•
CHANNEL 2
SELECTOR
Power-Down
5
DIVIDER
PHASE
5-BIT
CW_M2
VGA Clamp
I Q
I/Q
SR
V
REF
CW_IOUT2+
CW_QOUT2-
Ultrasound VGA Integrated
High-Level CW Mixer and Programmable
GND
CW_FILTER
The MAX2038 CW mixers are designed using an active
double-balanced topology. The mixers achieve high
dynamic range and high linearity performance, with
exceptionally low noise, which is ideal for ultrasound
CWD signal reception. The octal quadrature mixer
array provides noise performance of -155dBc/Hz at
1kHz from a 1.25MHz carrier, and a two-tone third-
order ultrasound specific intermodulation product of
typically -50dBc. See the Ultrasound-Specific IMD3
Specification in the Applications Information section .
The octal array exhibits quadrature and in-phase differ-
ential current outputs (CW_QOUT+, CW_QOUT-,
CW_IOUT+, CW_IOUT-) to produce the total CWD
beamformed signal. The maximum differential current
output is typically 3mA
ance voltage ranges from 4.75V to 12V.
LOW_PWR
Beamformer Functional Diagram
with CW Octal Mixer
Octal Continuous Wave (CW) Mixer
M4_EN
PD
I Q
CHANNEL 8
SELECTOR
5
DIVIDER
PHASE
5-BIT
SR
I/Q
MAX2038
P-P
and the mixer output-compli-
LO1
LO2
LO8
DOUT
CW_IOUT+
CW_IOUT-
CW_QOUT-
CW_QOUT+
•
• •
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