Datasheet
TYPICAL CHARACTERISTICS: V
S
= ± 5V, DC Parameters
10
1
0.1
GainResistor( )W
DifferentialInputVoltage(V )
PP
10 100 1k
I =2.6mA
RG MAX
V (V )=2 ´ R I (A )´
INMAX PP G RG MAX P
40
35
30
25
20
15
10
5
0
FeedbackResistor( )W
MaximumGainAdjustRange(dB)
100 1k 10k
I =2.6mA
RG
A (V/V)=2 ´ [R /V (V )] 2 I (A´ ´ )
VMAX F IN PP PRG
V =1V
O PP
V =2V
O PP
V =4V
O PP
V =3V
O PP
60
50
40
30
20
10
0
OutputVoltage(V )
PP
MaximumGainAdjustRange(dB)
0.1 1 10
I =2.6mA
RG
A (V/V)=2 ´ [R /V (V )] 2 I (A´ ´ )
VMAX F
IN
PPP RG
R
F
=3kW
R
F
=2kW
R
F
=1.5kW
R
F
=1kW
R
F
=500W
R
F
=4kW
R
F
=5kW
ControlVoltage(V)
0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain(V/V)
12
10
8
6
4
2
0
RelativeErrorto
MaximumGain
Absolute
Error
Absolute
Error
ControlVoltage(V)
0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain(dB)
40
20
0
-20
-40
-60
-80
-100
A(V/V)=K ´ ´
R
F
R
G
1
1+e
V =0.85V
CTRL0
V =90mV
SLOPE
V -V
G0 G
V
SLOPE
( )
Equation
Data
460
450
440
430
420
410
400
390
A (V/V)
VMAX
FeedbackResistor( )
W
1 10 100
For>40dBGainAdjustRange
NOTE: 3dBbandwidthvarieswithpackagetype.-
Seethe sectionformoredetails.ApplicationsInformation
VCA821
www.ti.com
....................................................................................................................................... SBOS407B – DECEMBER 2007 – REVISED DECEMBER 2008
At T
A
= +25 ° C, R
L
= 100 Ω , V
G
= +2V, and V
IN
= single-ended input on +V
IN
with – V
IN
at ground, unless otherwise noted.
MAXIMUM DIFFERENTIAL INPUT VOLTAGE vs R
G
MAXIMUM GAIN ADJUST RANGE vs R
F
Figure 1. Figure 2.
MAXIMUM GAIN ADJUST RANGE vs GAIN ERROR BAND vs
PEAK-TO-PEAK OUTPUT VOLTAGE GAIN CONTROL VOLTAGE
Figure 3. Figure 4.
GAIN ERROR BAND vs
GAIN CONTROL VOLTAGE RECOMMENDED R
F
vs A
VMAX
Figure 5. Figure 6.
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