AFE5851 Datasheet, PDF (1/41 Pages) Texas Instruments – 16 CHANNEL VARIABLE GAIN AMPLIFIER (VGA) WITH OCTAL HIGH SPEED ADC

AFE5851
www.ti.com
SLOS574B – SEPTEMBER 2008 – REVISED MAY 2010
16 CHANNEL VARIABLE GAIN AMPLIFIER (VGA) WITH OCTAL HIGH SPEED ADC
Check for Samples: AFE5851
FEATURES
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• 16 Variable Gain Amplifiers (VGA)
– 16 Single-Ended Buffered Inputs With 1V_PP
Maximum Swing
– 5.5nV/√Hz VCA Input Noise (31dB Gain).
– Variable Gain –5dB to 31dB With 0.125dB
Steps
– Digital Gain Control
• 3^rd Order Anti-Aliasing Filter With
Programmable Cut-Off Frequency (7.5, 10 and
14MHz).
• Clamping
• Analog-to-Digital Converter (ADC)
– Octal channel 12-bit, 65 MSPS
– 32.5 MSPS Maximum per Input Channel
– 2 VGA Outputs Alternately Sampled by
Each ADC
– Internal and External Reference Support
– No External Decoupling Required for
References
– Serial LVDS Outputs
• 1.8V and 3.3V Supply
• 39 mW Total Power per Channel at 32.5 MSPS
• 64-QFN Package (9mm × 9mm)
APPLICATIONS
• Imaging: Ultrasound, PET
DESCRIPTION
The AFE5851 is an analog front-end targeting
applications where the power and level of integration
are critical. The device contains 16 variable gain
amplifiers (VGA), followed by an octal high speed (up
to 65 MSPS) analog to digital converter (ADC).
Each of the 16 single ended inputs is buffered,
accepts up to 1V_PP maximum input swing and it is
followed by a VGA with a gain range from –5dB to
31dB. The VGA gain is digitally controlled and the
gain curves versus time can be stored in memory,
integrated within the device using the serial interface.
A selectable clamping and anti-alias low pass filter
(with 3dB attenuation at 7.5, 10 or 14MHz) is also
integrated between the VGA and ADC for every
channel. The VGA/anti-alias filter outputs are
differential (limited to 2 V_PP) and drive the on-board
12-bit 65MSPS ADC that is shared between two
VGAs to optimize the power dissipation. Each VGA
output is sampled at alternate clock cycles, making
the effective sampling frequency half the input clock
rate. The ADC also scales down its power
consumption should a lower sampling rate be
selected.
The ADC outputs are serialized in LVDS streams
further minimizing power and board area. The
AFE5851 is available in a 64-pin QFN package
(9x9mm²) and is specified over the full industrial
temperature range (–40°C to 85°C).
RELATED DEVICES
• AFE5801: Octal VGA+ADC, 65 MSPS/channel
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Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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