VCA2613
V
C
A
2
6
1
3
SBOS179D – DECEMBER 2000 – REVISED OCTOBER 2004
Dual, VARIABLE GAIN AMPLIFIER
with Low-Noise Preamp
FEATURES
DESCRIPTION
The VCA2613 is a dual, Low-Noise Preamplifier (LNP), plus
low-noise Variable Gain Amplifier (VGA). The combination of
Active Termination (AT) and Maximum Gain Select (MGS)
allow for the best noise performance. The VCA2613 also
features low crosstalk and outstanding distortion perfor-
mance.
● LOW NOISE PREAMP:
Low Input Noise: 1.0nV/√Hz
Active Termination Noise Reduction
Switchable Termination Value
80MHz Bandwidth
5dB to 25dB Gain
The LNP has differential input and output capability and is
strappable for gains of 5dB, 17dB, 22dB or 25dB. Low input
impedance is achieved by AT, resulting in as much as a 4.6dB
improvement in noise figure over conventional shunt termina-
tion. The termination value can also be switched to accommo-
date different sources. The output of the LNP is available for
external signal processing.
Differential In and Out
● LOW NOISE VARIABLE GAIN AMPLIFIER:
Low Noise VCA: 3.3nV/√Hz, Differential
Programming Optimizes Noise Figure
24dB to 45dB Gain
40MHz Bandwidth
Differential In and Out
The variable gain is controlled by an analog voltage whose
gain varies from 0dB to the gain set by the MGS. The ability
to program the variable gain also allows the user to optimize
dynamic range. The VCA input can be switched from the
LNP to external circuits for different applications. The output
can be used in either a single-ended or differential mode to
drive high-performance Analog-to-Digital (A/D) converters,
and is cleanly limited for optimum overdrive recovery.
● LOW CROSSTALK: 52dB at Max Gain, 5MHz
● HIGH-SPEED VARIABLE GAIN ADJUST
● SWITCHABLE EXTERNAL PROCESSING
APPLICATIONS
The combination of low noise, gain, and gain range program-
mability makes the VCA2613 a versatile building block in a
number of applications where noise performance is critical.
The VCA2613 is available in a TQFP-48 package.
● ULTRASOUND SYSTEMS
● WIRELESS RECEIVERS
● TEST EQUIPMENT
Maximum Gain Select
VCACNTL
FBCNTL
LNPOUTN
VCAINN
MGS0 MGS1 MGS2
RF2
RF1
FBSW
FB
VCA2613
(1 of 2 Channels)
Analog
Control
Maximum Gain
Select
Input
LNPIN
P
VCAOUTN
LNPGS1
LNPGS2
Programmable
Gain Amplifier
24 to 45dB
Voltage
Controlled
Attenuator
Low Noise
Preamp
5dB to 25dB
LNP
Gain Set
LNPGS3
VCAOUT
P
LNPIN
N
LNPOUT
P
VCAIN
P
SEL
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PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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