VCA610_08 Datasheet, PDF (1/14 Pages) Texas Instruments – WIDEBAND VOLTAGE CONTROLLED AMPLIFIER

VCA610
VCA610
www.ti.com
WIDEBAND
VOLTAGE CONTROLLED AMPLIFIER
FEATURES
q WIDE GAIN CONTROL RANGE: 77dB
q SMALL PACKAGE: SO-8
q WIDE SIGNAL BANDWIDTH: 30MHz
q LOW VOLTAGE NOISE: 2.2nV/√Hz
q FAST GAIN SLEW RATE: 300dB/µs
DESCRIPTION
The VCA610 is a wideband, continuously variable,
voltage-controlled gain amplifier. It provides
linear-dB gain control with high impedance inputs.
It is designed to be used as a flexible gain-control
element in a variety of electronic systems.
The VCA610 has a gain-control range of 77dB
(–38.5dB to +38.5dB) providing both gain and attenu-
ation for maximum flexibility in a small SO-8. The
broad attenuation range can be used for gradual or
controlled channel turn-on and turn-off for applica-
tions in which abrupt gain changes can create artifacts
or other errors. In addition, the output can be disabled
to provide –77dB of attenuation. Group delay varia-
tion with gain is typically less than ±2ns across a
bandwidth of 1MHz to 15MHz.
The VCA610 has a noise figure of 3.5dB (with an R_S
of 200Ω) including the effects of both current and
voltage noise. Instantaneous output dynamic range is
70dB for gains of 0dB to +38.5dB with 1MHz noise
bandwidth. The output is capable of driving 100Ω.
The high-speed, 300dB/µs, gain-control signal is a
unipolar (0V to –2V) voltage that varies the gain
linearly in dB/V over a –38.5dB to +38.5dB range.
APPLICATIONS
q OPTICAL DISTANCE MEASUREMENT
q AGC AMPLIFIERS
q ULTRASOUND
q SONAR
q ACTIVE FILTERS
q LOG AMPLIFIERS
q IF CIRCUITS
q CCD CAMERAS
The VCA610 is designed with a very fast overload
recovery time of only 200ns. This allows a large
signal transient to overload the output at high gain,
without obscuring low-level signals following closely
behind. The excellent overload recovery time and
distortion specifications optimize this device for low-
level doppler measurements.
+5V –5V
6 72
8
–In
1
+In
3
V_C
Gain
Control
VCA610
5
V_OUT
Copyright © 2000, Texas Instruments Incorporated
SBOS013A
Printed in U.S.A. November, 2000