VCA2619 Datasheet, PDF (11/19 Pages) Burr-Brown (TI) – Dual, Variable Gain Amplifier with Input Buffer

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VCA2619
SBOS276A − AUGUST 2003 − REVISED AUGUST 2003
Attenuator
Input
R_S
A1 to A10 Attenuator Stages
Q_S
Attenuator
Output
V_CM
A1
Q₁
A2
Q₂
A3
Q₃
A4
Q₄
A5
Q₅
A6
Q₆
A7
Q₇
A8
Q₈
A9
Q₉
Q₁₀
A10
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
V1
V2
V3
V4
V5
V6
V7
V8
V9
V10
Control
Input
C1 to C10 Clipping Amplifiers
0dB
−5.2dB
V_CM − V_T
Attenuation Characteristic of Individual FETs
0
V1
V2
V3
V4
V5
V6
V7
V8
V9
V10
Characteristic of Attenuator Control Stage Output
OVERALL CONTROL CHARACTERISTICS OF ATTENUATOR
0dB
−52.3dB
0.2V
Control Signal
3V
Figure 4. Piecewise Approximation to Logarithmic Control Characteristics.
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