CLC522 Datasheet, PDF (1/8 Pages) National Semiconductor (TI) – Wideband Variable-Gain Amplifier

N
June 1999
CLC522
Wideband Variable-Gain Amplifier
General Description
The CLC522 variable gain amplifier (VGA) is a dc-coupled, two-
quadrant multiplier with differential voltage inputs and a single-ended
voltage output. Two input buffers and an output operational amplifer
are integrated with the multiplier core to make the CLC522 a complete
VGA system that does not require external buffering.
The CLC522 provides the flexibility of externally setting the maximum
gain with only two external resistors. Greater than 40dB gain control
is easily achieved through a single high impedance voltage input. The
CLC522 provides a linear (in Volts per Volt) relationship between the
amplifier's gain and the gain-control input voltage.
The CLC522's maximum gain may be set anywhere over a nominal
range of 2V/V to 100V/V. The gain control input then provides
attenuation from the maximum setting. For example, set for a
maximum gain of 100V/V, the CLC522 will provide a 100V/V to 1V/V
gain control range by sweeping the gain control input voltage from +1
to -0.98V.
Set at a maximum gain of 10V/V, the CLC522 provides a 165MHz
signal channel bandwidth and a 165MHz gain control bandwidth. Gain
nonlinearity over a 40dB gain range is 0.5% and gain accuracy at
A_Vmax = 10V/V is typically ±0.3%.
Features
s 330MHz signal bandwidth: A_vmax = 2
s 165MHz gain-control bandwidth
s 0.3° to 60MHz linear phase deviation
s 0.04% (-68dB) signal-channel non-linearity
s >40dB gain-adjustment range
s Differential or single-end voltage inputs
s Single-ended voltage output
Applications
s Variable attenuators
s Pulse amplitude equalizers
s HF modulators
s Automatic gain control & leveling loops
s Video production switching
s Differential line receivers
s Voltage controlled filters
Gain vs. Gain Control Voltage (Vg)
10
0
-1.1
Gain Control Voltage, V_g (Volts)
1.1
Typical Application
2nd Order Tuneable Bandpass Filter
Pinout
DIP & SOIC
© 1999 National Semiconductor Corporation
Printed in the U.S.A.
1
s
V_o
V_in
=


−
1
n^
s²
+s
CR_b
1₊
CR_b
k
C ²R _y ²
k = 1.85 ^Rf , Q =
R_g
k R_b
R_y
,
ω_o
=
k
CR_y
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