VCA821IDG4 [TI]
Wideband, > 40dB Adjust Range, Linear in dB Variable Gain Amplifier 14-SOIC -40 to 85;型号: | VCA821IDG4 |
厂家: | TEXAS INSTRUMENTS |
描述: | Wideband, > 40dB Adjust Range, Linear in dB Variable Gain Amplifier 14-SOIC -40 to 85 光电二极管 |
文件: | 总38页 (文件大小:1680K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
Ultra-Wideband, > 40dB Gain Adjust Range, Linear in dB
VARIABLE GAIN AMPLIFIER
1
FEATURES
DESCRIPTION
23
•
710MHz SMALL-SIGNAL BANDWIDTH
(G = +2V/V)
The VCA821 is a dc-coupled, wideband, linear in dB,
continuously variable, voltage-controlled gain
amplifier. It provides differential input to
single-ended conversion with a high-impedance gain
control input used to vary the gain down 40dB from
the nominal maximum gain set by the gain resistor
(RG) and feedback resistor (RF).
•
320MHz, 4VPP BANDWIDTH (G = +10V/V)
0.1dB GAIN FLATNESS to 135MHz
2500V/µs SLEW RATE
a
•
•
•
•
•
> 40dB GAIN ADJUST RANGE
HIGH GAIN ACCURACY: 20dB ±0.3dB
HIGH OUTPUT CURRENT: ±90mA
The VCA821 internal architecture consists of two
input buffers and an output current feedback amplifier
stage integrated with a multiplier core to provide a
complete variable gain amplifier (VGA) system that
does not require external buffering. The maximum
gain is set externally with two resistors, providing
flexibility in designs. The maximum gain is intended
to be set between 6dB and 32dB. Operating from ±5V
supplies, the gain control voltage for the VCA821
adjusts the gain linearly in dB as the control voltage
varies from 0V to +2V. For example, set at a
maximum gain of 20dB, the VCA821 provides 20dB,
at VG = +2V, to less than –20dB at VG = 0V. The
VCA821 offers excellent gain linearity. For a 20dB
maximum gain, and a gain-control input voltage
varying between +1V and +2V, the gain does not
deviate by more than ±0.3dB (maximum at +25°C).
APPLICATIONS
•
•
•
•
•
AGC RECEIVERS with RSSI
DIFFERENTIAL LINE RECEIVERS
PULSE AMPLITUDE COMPENSATION
VARIABLE ATTENUATORS
VOLTAGE-TUNABLE ACTIVE FILTERS
RF
VIN1
+VIN
RG+
RS
RL
FB
VCA821
R1
C1
RG
VOUT
CL
RG-
VIN2
-VIN
20W
RS
VCA821 RELATED PRODUCTS
GAIN
ADJUST
RANGE
(dB)
INPUT
NOISE
(nV/√Hz)
SIGNAL
BANDWIDTH
(MHz)
Differential Equalizer
SINGLES
VCA810
—
DUALS
—
80
45
45
52
48
40
40
40
40
2.4
1.25
1
35
80
9
6
Equalized Frequency Response
VCA2612
VCA2613
VCA2615
VCA2617
—
3
—
80
0
—
0.8
4.1
8.2
6.0
8.2
6.0
50
Initial Frequency Response
of the VCA821 with RC Load
-3
-6
-9
—
50
VCA820
VCA821
VCA822
VCA824
150
420
150
420
-12
-15
-18
-21
-24
—
—
—
1M
10M
100M
1G
Frequency (Hz)
Differential Equalization of an RC Load
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2
3
X2Y is a trademark of X2Y Attenuators LLC.
All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2007–2008, Texas Instruments Incorporated
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
ORDERING INFORMATION(1)
SPECIFIED
PACKAGE
TEMPERATURE
RANGE
PACKAGE
MARKING
ORDERING
NUMBER
TRANSPORT
MEDIA, QUANTITY
PRODUCT PACKAGE-LEAD DESIGNATOR
VCA821ID
VCA821IDR
Rail, 50
VCA821
VCA821
SO-14
D
–40°C to +85°C
–40°C to +85°C
VCA821ID
BOR
Tape and Reel, 2500
Tape and Reel, 250
Tape and Reel, 2500
VCA821IDGST
VCA821IDGSR
MSOP-10
DGS
(1) For the most current package and ordering information see the Package Option Addendum at the end of this document, or see the TI
web site at www.ti.com.
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted)
VCA821
UNIT
Power Supply
±6.5
V
Internal Power Dissipation
See Thermal Characteristics
Input Voltage Range
±VS
–65 to +125
+260
V
°C
°C
°C
C
Storage Temperature Range
Lead Temperature (soldering, 10s)
Junction Temperature (TJ)
+150
Junction Temperature (TJ), Maximum Continuous Operation
Human Body Model (HBM)
ESD Rating: Charge Device Model (CDM)
Machine Model
+140
2000
V
1000
V
200
V
PIN CONFIGURATIONS
D PACKAGE
SO-14
DGS PACKAGE
MSOP-10
(TOP VIEW)
(TOP VIEW)
+VCC
NC
GND
+VCC
VG
1
2
3
4
5
6
7
14
13
12
11
10
9
FB
+VCC
VG
1
2
3
4
5
10
9
VOUT
-VCC
-VIN
-RG
FB
+VIN
+RG
-RG
-VIN
-VCC
8
GND
VOUT
VREF
-VCC
+VIN
+RG
7
6
8
NC = No Connection
2
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
ELECTRICAL CHARACTERISTICS: VS = ±5V
At AVMAX = 20dB, RF = 402Ω, RG = 80Ω, RL = 100Ω, unless otherwise noted.
VCA821
MIN/MAX OVER
TYP
TEMPERATURE
0°C to
70°C(3)
–40°C to
+85°C(3)
MIN/
MAX
TEST
PARAMETER
CONDITIONS
+25°C
+25°C(2)
UNITS
LEVEL(1)
AC PERFORMANCE
Small-Signal Bandwidth
G = 6dB, VO = 500mVPP
G = 20dB, VO = 500mVPP
G = 40dB, VO = 500mVPP
G = 20dB, VO = 4VPP
710
420
170
320
330
135
2500
1.5
MHz
MHz
MHz
MHz
MHz
MHz
V/µs
ns
typ
typ
C
C
C
C
B
C
B
B
C
typ
Large-Signal Bandwidth
Gain Control Bandwidth
Bandwidth for 0.1dB Flatness
Slew Rate
typ
VO = 200mVPP
240
235
235
min
typ
G = 20dB, VO = 200mVPP
G = 20dB, VO = 5V Step
G = 20dB, VO = 5V Step
G = 20dB, VO = 5V Step
1800
1.8
1700
1.9
1700
1.9
min
max
typ
Rise-and-Fall Time
Settling Time to 0.01%
Harmonic Distortion
2nd Harmonic
11
ns
VO = 2VPP, f = 20MHz
VO = 2VPP, f = 20MHz
f > 100kHz
–66
–63
6.0
2.6
–64
–61
–64
–61
–64
–61
dBc
dBc
min
min
typ
B
B
C
C
3rd Harmonic
Input Voltage Noise
Input Current Noise
GAIN CONTROL
Absolute Gain Error
Vctrl0
nV/√Hz
pA/√Hz
f > 100kHz
typ
GMAX = 20dB, VG = 2V
±0.1
0.85
0.09
±0.3
±0.4
±0.4
±0.5
±0.5
±0.6
±0.6
dB
V
max
typ
A
C
C
A
VSlope
V
typ
Absolute Gain Error
GMAX = 20dB, VG = 1V, (G = 18.06
dB)
dB
max
Gain at VG = 0.2V
relative to max gain
–26
10
–24
16
–24
16.6
±12
–23
16.7
±12
dB
µA
max
max
max
typ
A
A
B
C
Gain Control Bias Current
Average Gain Control Bias Current Drift
nA/°C
MΩ || pF
Gain Control Input Impedance
DC PERFORMANCE
1.5 || 0.6
±4
Input Offset Voltage
G = 20dB, VCM = 0V, VG = 1V
G = 20dB, VCM = 0V, VG = 1V
G = 20dB, VCM = 0V, VG = 1V
G = 20dB, VCM = 0V, VG = 1V
G = 20dB, VCM = 0V, VG = 1V
G = 20dB, VCM = 0V, VG = 1V
±17
25
±17.8
30
±19
30
mV
µV/°C
µA
max
max
max
max
max
max
max
A
B
A
B
A
B
B
Average Input Offset Voltage Drift
Input Bias Current
Average Input Bias Current Drift
Input Offset Current
Average Input Offset Current Drift
19
29
31
90
90
nA/°C
µA
±0.5
±2.6
±2.5
±2.55
±3.2
±16
±2.55
±3.5
±16
±2.5
nA/°C
mA
Max Current Through Gain Resistance
INPUT
Most Positive Common Mode Input Voltage
Most Negative Common Mode Input Voltage
Common-Mode Rejection Ratio
Input Impedance
RL = 100Ω
RL = 100Ω
VCM = ±0.5V
+1.6
–2.1
80
+1.6
-2.1
65
+1.6
–2.1
60
+1.6
–2.1
60
V
V
min
max
min
A
A
A
dB
Differential
0.9 || 0.6
1 || 2
MΩ || pF
MΩ || pF
typ
typ
C
C
Common-Mode
(1) Test levels: (A) 100% tested at +25°C. Over temperature limits set by characterization and simulation. (B) Limits set by characterization
and simulation. (C) Typical value only for information.
(2) Junction temperature = ambient for +25°C tested specifications.
(3) Junction temperature = ambient at low temperature limit; junction temperature = ambient +23°C at high temperature limit for over
temperature specifications.
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
3
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
ELECTRICAL CHARACTERISTICS: VS = ±5V (continued)
At AVMAX = 20dB, RF = 402Ω, RG = 80Ω, RL = 100Ω, unless otherwise noted.
VCA821
MIN/MAX OVER
TYP
TEMPERATURE
0°C to
70°C(3)
–40°C to
+85°C(3)
MIN/
MAX
TEST
PARAMETER
OUTPUT
CONDITIONS
+25°C
+25°C(2)
UNITS
LEVEL(1)
Output Voltage Swing
RL = 1kΩ
RL = 100Ω
±3.9
±3.6
±90
±3.6
±3.5
±60
±3.4
±3.3
±50
±3.3
±3.2
±45
V
V
min
min
min
typ
A
A
A
C
Output Current
VO = 0V, RL = 10Ω
G = +10V/V, f > 100kHz
mA
Ω
Output Impedance
0.01
POWER SUPPLY
Specified Operating Voltage
Minimum Operating Voltage
Maximum Operating Voltage
Maximum Quiescent Current
Minimum Quiescent Current
Power-Supply Rejection Ratio (–PSRR)
THERMAL CHARACTERISTICS
Specified Operating Range D Package
Thermal Resistance θJA
±5
V
V
typ
typ
C
C
A
A
A
A
±3.5
±6
35
±6
35.5
32
±6
36
V
max
max
max
min
VG = 1V
VG = 1V
34
34
mA
mA
dB
32.5
–61
31.5
–58
–68
–59
–40 to +85
°C
typ
C
Junction-to-Ambient
DGS MSOP-10
130
80
°C/W
°C/W
typ
typ
C
C
D
SO-14
4
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
TYPICAL CHARACTERISTICS: VS = ±5V, DC Parameters
At TA = +25°C, RL = 100Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless otherwise noted.
MAXIMUM DIFFERENTIAL INPUT VOLTAGE vs RG
MAXIMUM GAIN ADJUST RANGE vs RF
10
40
35
30
25
20
15
10
5
IRG MAX = 2.6mA
IRG = 2.6mA
VIN MAX(VPP) = 2 ´ RG ´ IRG MAX (AP)
AVMAX(V/V) = 2 ´ [RF/VIN(VPP)] ´ 2 ´ IRG (AP)
VO = 1VPP
VO = 2VPP
1
VO = 4VPP
VO = 3VPP
0
0.1
10
100
1k
100
1k
10k
Gain Resistor (W)
Figure 1.
Feedback Resistor (W)
Figure 2.
MAXIMUM GAIN ADJUST RANGE vs
PEAK-TO-PEAK OUTPUT VOLTAGE
GAIN ERROR BAND vs
GAIN CONTROL VOLTAGE
12
10
8
60
50
40
30
20
10
0
Absolute
Error
IRG = 2.6mA
AVMAX(V/V) = 2 ´ [RF/V (VPP)] ´ 2 ´ IRG (AP)
IN
RF = 3kW
Absolute
Error
RF = 4kW
RF = 5kW
6
Relative Error to
Maximum Gain
RF = 500W
4
RF = 1kW
2
RF = 1.5kW
RF = 2kW
0
0.1
1
10
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Control Voltage (V)
Output Voltage (VPP
)
Figure 3.
Figure 4.
GAIN ERROR BAND vs
GAIN CONTROL VOLTAGE
RECOMMENDED RF vs AVMAX
40
20
460
450
440
430
420
410
400
390
For > 40dB Gain Adjust Range
0
-20
-40
-60
-80
-100
Equation
RF
1
VG0 - VG
A(V/V) = K ´
´
RG
(
1 + e
)
VSLOPE
Data
VCTRL0 = 0.85V
VSLOPE = 90mV
NOTE: -3dB bandwidth varies with package type.
See the Applications Information section for more details.
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Control Voltage (V)
1
10
100
AVMAX (V/V)
Figure 5.
Figure 6.
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
5
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS: VS = ±5V, DC and Power-Supply Parameters
At TA = +25°C, RL = 100Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless otherwise noted.
SUPPLY CURRENT vs CONTROL VOLTAGE
(AVMAX = 6dB)
SUPPLY CURRENT vs CONTROL VOLTAGE
(AVMAX = 20dB)
36
35
34
33
32
31
30
29
36
35
34
33
32
31
30
29
+IQ
+IQ
-IQ
-IQ
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain Control Voltage (V)
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain Control Voltage (V)
Figure 7.
Figure 8.
SUPPLY CURRENT vs CONTROL VOLTAGE
(AVMAX = 32dB)
TYPICAL DC DRIFT vs TEMPERATURE
37
36
35
34
33
32
31
30
29
0
-0.5
-1.0
-1.5
-2.0
-2.5
-3.0
-3.5
-4.0
-4.5
30
-IQ
25
Input Bias Current (IB)
20
Right Scale
+IQ
15
10
Input Offset Voltage (VOS
)
5
Left Scale
0
-5
-10
-15
Right Scale
10 x Input Offset Current (IOS
)
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain Control Voltage (V)
-50
-25
0
25
50
75
100
125
Temperature (°C)
Figure 9.
Figure 10.
6
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 6dB
At TA = +25°C, RL = 100Ω, RF = 453Ω, RG = 453Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and
SO-14 package, unless otherwise noted.
SMALL-SIGNAL FREQUENCY RESPONSE
LARGE-SIGNAL FREQUENCY RESPONSE
3
0
3
0
VO = 1VPP
VG = +1V
VO = 2VPP
-3
-3
VG = +2V
-6
-6
VO = 4VPP
-9
-9
-12
-15
-18
-12
-15
-18
VO = 5VPP
AVMAX = 6dB
VIN = 1VPP
RL = 100W
1M
10M
100M
1G 2G
1M
10M
100M
1G 2G
Frequency (Hz)
Frequency (Hz)
Figure 11.
Figure 12.
SMALL-SIGNAL PULSE RESPONSE
LARGE-SIGNAL PULSE RESPONSE
300
4.0
V
= 2V
PP
IN
f = 20MHz
3.0
2.0
200
100
1.0
0
0
-100
-200
-300
-1.0
-2.0
-3.0
V
= 250mV
PP
IN
f = 20MHz
Time (10ns/div)
Time (10ns/div)
Figure 13.
Figure 14.
COMPOSITE VIDEO dG/dP
GAIN FLATNESS, DEVIATION FROM LINEAR PHASE
0.15
0
0.2
0.1
0
-0.1
-0.2
-0.3
-0.4
-0.5
-0.6
-0.7
-0.8
-0.9
Left Scale
0.10
-0.005
-0.010
-0.015
-0.020
-0.025
-0.030
-0.035
-0.040
-dG, VG = 0V
0
0.05
-0.1
-0.2
-0.3
-0.4
-0.5
0
-dP, VG = 0V
Right Scale
-0.05
-0.10
-dP, VG = +1V
-0.15
AVMAX = 6dB
VG = +2V
-dG, VG = +1V
-0.20
-0.045
0
50
100
150
200
1
2
3
4
Frequency (MHz)
Number of Video Loads
Figure 15.
Figure 16.
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
7
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 6dB (continued)
At TA = +25°C, RL = 100Ω, RF = 453Ω, RG = 453Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and
SO-14 package, unless otherwise noted.
HARMONIC DISTORTION vs
FREQUENCY
HARMONIC DISTORTION vs
LOAD RESISTANCE
-60
-65
-70
-75
-80
-85
-90
-60
-65
-70
-75
-80
-85
-90
AVMAX = 6dB
VG = +2V
VO = 2VPP
f = 20MHz
3rd Harmonic
2nd Harmonic
3rd Harmonic
AVMAX = 6dB
VG = +2V
2nd Harmonic
VO = 2VPP
RL = 100W
0.1
1
10
100
100
1k
Frequency (MHz)
Resistance (W)
Figure 17.
Figure 18.
HARMONIC DISTORTION vs
OUTPUT VOLTAGE
HARMONIC DISTORTION vs
GAIN CONTROL VOLTAGE
-10
-20
-30
-40
-50
-60
-70
-80
-90
-30
-35
-40
AVMAX = 6dB
AVMAX = 6dB
VO = 2VPP
RL = 100W
f = 20MHz
VG = +2V
Maximum Current
RL = 100W
Through RG Limited
-45 f = 20MHz
-50
-55
-60
-65
-70
-75
-80
Maximum Current Through RG Limited
2nd Harmonic
3rd Harmonic
2nd Harmonic
3rd Harmonic
-85
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0.1
1
10
Gain Control Voltage (V)
Output Voltage Swing (VPP
)
Figure 19.
Figure 20.
TWO-TONE, 3RD-ORDER INTERMODULATION INTERCEPT
vs
GAIN CONTROL VOLTAGE
40
TWO-TONE, 3RD-ORDER
INTERMODULATION INTERCEPT
38
36
34
32
30
28
26
24
Constant Input Voltage
35
30
Constant Output Voltage
25
20
15
f = 20MHz
At 50W Matched Load
10 20 30 40 50
At 50W Matched Load
10
0
60 70
80
90 100
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Frequency (MHz)
Gain Control Voltage (V)
Figure 21.
Figure 22.
8
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 6dB (continued)
At TA = +25°C, RL = 100Ω, RF = 453Ω, RG = 453Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and
SO-14 package, unless otherwise noted.
GAIN vs GAIN CONTROL VOLTAGE
GAIN CONTROL FREQUENCY RESPONSE
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
3
0
-3
-6
-9
-12
VG = 1VDC + 10mVPP
VIN =0.5VDC
-0.2
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain Control Voltage (V)
1M
10M
100M
Frequency (Hz)
1G
Figure 23.
Figure 24.
GAIN CONTROL PULSE RESPONSE
FULLY-ATTENUATED RESPONSE
20
10
4
VIN = 1VDC
3
VG = +2V
0
2
-10
-20
-30
-40
-50
-60
-70
-80
-90
1
VO = 2VPP
2.5
0
2.0
1.5
1.0
0.5
0
-1
VG = 0V
Input Referred
-0.5
1M
10M
100M
1G
Time (10ns/div)
Frequency (Hz)
Figure 25.
Figure 26.
GROUP DELAY vs GAIN CONTROL VOLTAGE
GROUP DELAY vs FREQUENCY
2.0
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
10MHz
1MHz
20MHz
VG = +2V
VO = 1VPP
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain Control Voltage (V)
0
20
40
60
80
100
Frequency (MHz)
Figure 27.
Figure 28.
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
9
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 6dB (continued)
At TA = +25°C, RL = 100Ω, RF = 453Ω, RG = 453Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and
SO-14 package, unless otherwise noted.
RECOMMENDED RS vs CAPACITIVE LOAD
FREQUENCY RESPONSE vs CAPACITIVE LOAD
9
6
100
10
1
VO = 0.5VPP
CL = 10pF
CL = 22pF
CL = 100pF
3
CL = 47pF
0
RF
VIN
+
-3
-6
-9
RS
VOUT
VCA821
1kW(1)
CL
-
NOTE: (1) 1kW is optional.
0.1dB Flatness Targeted
1
10
100
1k
1
10
100
1k
Capacitive Load (pF)
Capacitive Load (pF)
Figure 29.
Figure 30.
OUTPUT VOLTAGE NOISE DENSITY
INPUT CURRENT NOISE DENSITY
200
100
10
VG = +1V
VG = +2V
VG = 0V
10
1
100
1k
10k
100k
1M
10M
100
1k
10k
100k
1M
10M
Frequency (Hz)
Frequency (Hz)
Figure 31.
Figure 32.
10
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 20dB
At TA = +25°C, RL = 100Ω, RF = 402Ω, RG = 80Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless
otherwise noted.
SMALL-SIGNAL FREQUENCY RESPONSE
LARGE-SIGNAL FREQUENCY RESPONSE
3
0
3
0
VG = +1V
VO = 1VPP
VO = 2VPP
-3
-3
-6
-6
VG = +2V
-9
-9
VO = 4VPP
VO = 5VPP
-12
-15
-18
-12
-15
-18
AVMAX = 20dB
VIN = 200mVPP
RL = 100W
1M
10M
100M
Frequency (Hz)
1G
1M
10M
100M
Frequency (Hz)
1G
Figure 33.
Figure 34.
LARGE-SIGNAL PULSE RESPONSE
SMALL-SIGNAL PULSE RESPONSE
300
3
2
200
100
1
0
0
-100
-200
-300
-1
-2
-3
V
= 400mV
PP
V
= 50mV
PP
IN
f = 20MHz
IN
f = 20MHz
Time (10ns/div)
Time (10ns/div)
Figure 35.
Figure 36.
GAIN FLATNESS, DEVIATION FROM LINEAR PHASE
0.20
OUTPUT VOLTAGE NOISE DENSITY
200
100
0.1
0
0.15
VG = +2V
Left Scale
0.10
-0.1
-0.2
-0.3
-0.4
-0.5
-0.6
VG = 0V
0.05
0
Right Scale
VG = +1V
-0.05
-0.10
AVMAX = 20dB
VG = +2V
-0.15
10
0
50
100
150
200
100
1k
10k
100k
1M
10M
Frequency (MHz)
Frequency (Hz)
Figure 37.
Figure 38.
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
11
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 20dB (continued)
At TA = +25°C, RL = 100Ω, RF = 402Ω, RG = 80Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless
otherwise noted.
HARMONIC DISTORTION vs
FREQUENCY
HARMONIC DISTORTION vs
LOAD RESISTANCE
-50
-55
-60
-65
-70
-75
-80
-85
-66
-68
-70
-72
-74
-76
-78
-80
AVMAX = 20dB
VG = +2V
VO = 1VPP
f = 20MHz
3rd Harmonic
3rd Harmonic
AVMAX = 20dB
VG = +2V
2nd Harmonic
VO = 2VPP
RL = 100W
2nd Harmonic
0.1
1
10
100
100
1k
Frequency (MHz)
Resistance (W)
Figure 39.
Figure 40.
HARMONIC DISTORTION vs
OUTPUT VOLTAGE
HARMONIC DISTORTION vs
GAIN CONTROL VOLTAGE
-10
-20
-30
-40
-50
-60
-70
-80
-90
-20
-30
-40
-50
-60
-70
-80
-90
AVMAX = +10V/V
AVMAX = 20dB
VG = +2V
RL = 100W
f = 20MHz
VO = 2VPP
RL = 100W
f = 20MHz
Maximum Current
Through RG Limited
Maximum Current through
RG Limited.
2nd Harmonic
2nd Harmonic
3rd Harmonic
3rd Harmonic
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0.1
1
10
Gain Control Voltage (V)
Output Voltage Swing (VPP
)
Figure 41.
Figure 42.
TWO-TONE, 3RD-ORDER INTERMODULATION INTERCEPT
vs
GAIN CONTROL VOLTAGE
40
TWO-TONE, 3RD-ORDER
INTERMODULATION INTERCEPT
37
35
33
31
29
27
Constant Input Voltage
35
30
25
Constant Output Voltage
20
VG = +2V
At 50W Matched Load
f = 20MHz
At 50W Matched Load
15
0
10
20
30
40 50
60 70
80
90 100
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Frequency (MHz)
Gain Control Voltage (V)
Figure 43.
Figure 44.
12
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 20dB (continued)
At TA = +25°C, RL = 100Ω, RF = 402Ω, RG = 80Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless
otherwise noted.
GAIN vs GAIN CONTROL VOLTAGE
GAIN CONTROL FREQUENCY RESPONSE
11
10
9
3
0
8
7
-3
6
5
-6
4
3
-9
2
1
-12
-15
VG = 1VDC + 10mVPP
VIN = 0.1VDC
0
-1
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain Control Voltage (V)
1M
10M
100M
Frequency (Hz)
1G
Figure 45.
Figure 46.
GAIN CONTROL PULSE RESPONSE
OUTPUT VOLTAGE AND CURRENT LIMITATIONS
4
5
4
1W Internal
Power
VIN = 0.2VDC
3
100W
Dissipation
2
3
Load
1
2
2.5
0
1
50W
2.0
1.5
1.0
0.5
0
-1
0
Load
25W
-1
-2
-3
-4
-5
Load
1W Internal
Power
Dissipation
-0.5
-150
-100
-50
0
50
100
150
Time (10ns/div)
Output Current (mA)
Figure 47.
Figure 48.
FULLY-ATTENUATED RESPONSE
IRG LIMITED OVERDRIVE RECOVERY
30
20
10
0
0.4
0.3
2.0
AVMAX = +10V/V
Input Voltage
VG = 0.7V
1.5
VG = +2V
Left Scale
0.2
1.0
-10
-20
-30
-40
-50
-60
-70
-80
-90
0.1
0.5
VO = 2VPP
0
0
Output Voltage
Right Scale
-0.1
-0.2
-0.3
-0.4
-0.5
-1.0
-1.5
-2.0
Input Referred
VG = 0V
Time (40ns/div)
1M
10M
100M
1G
Frequency (Hz)
Figure 49.
Figure 50.
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
13
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 20dB (continued)
At TA = +25°C, RL = 100Ω, RF = 402Ω, RG = 80Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless
otherwise noted.
OUTPUT LIMITED OVERDRIVE RECOVERY
GROUP DELAY vs GAIN CONTROL VOLTAGE
0.6
0.4
6
1.65
1.60
1.55
1.50
1.45
1.40
AVMAX = +10V/V
VG = +2V
10MHz
4
Output Voltage
Right Scale
0.2
2
0
0
1MHz
-0.2
-0.4
-0.6
-2
-4
-6
20MHz
Input Voltage
Left Scale
Time (40ns/div)
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain Control Voltage (V)
Figure 51.
Figure 52.
GROUP DELAY vs FREQUENCY
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
VG = +2V
VO = 1VPP
0
20
40
60
80
100
Frequency (MHz)
Figure 53.
14
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 32dB
At TA = +25°C, RL = 100Ω, RF = 402Ω, RG = 18Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14
package, unless otherwise noted.
SMALL-SIGNAL FREQUENCY RESPONSE
LARGE-SIGNAL FREQUENCY RESPONSE
3
0
3
0
VO = 1VPP, 2VPP, 4VPP, 5VPP
-3
-3
VG = +1V
VG = +2V
-6
-6
-9
-9
-12
-15
-18
-12
-15
-18
AVMAX = 32dB
VIN = 50mVPP
RL = 100W
1M
10M
100M
Frequency (Hz)
1G
0
100
200
300
400
500
Frequency (MHz)
Figure 54.
Figure 55.
SMALL-SIGNAL PULSE RESPONSE
LARGE-SIGNAL PULSE RESPONSE
400
2.5
2.0
1.5
300
200
100
0
1.0
0.5
0
-0.5
-1.0
-1.5
-2.0
-2.5
-100
-200
-300
V
= 12.5mV
PP
V
= 100mV
PP
IN
IN
f = 20MHz
f = 20MHz
Time (10ns/div)
Time (10ns/div)
Figure 56.
Figure 57.
GAIN FLATNESS, DEVIATION FROM LINEAR PHASE
0.15
OUTPUT VOLTAGE NOISE DENSITY
1000
100
10
0.2
0.1
AVMAX = 32dB
VG = +2V
0.10
0.05
0
0
VG = +2V
VG = +1V
-0.1
-0.2
-0.3
-0.4
-0.5
-0.05
-0.10
-0.15
-0.20
VG = 0V
0
20
40
60
200
100
1k
10k
100k
1M
10M
Frequency (MHz)
Frequency (Hz)
Figure 58.
Figure 59.
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
15
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 32dB (continued)
At TA = +25°C, RL = 100Ω, RF = 402Ω, RG = 18Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14
package, unless otherwise noted.
HARMONIC DISTORTION vs
FREQUENCY
HARMONIC DISTORTION vs
LOAD RESISTANCE
-35
-40
-45
-50
-55
-60
-65
-70
-50
-55
-60
-65
-70
-75
-80
-85
AVMAX = 32dB
VG = +2V
VO = 2VPP
RL = 100W
3rd Harmonic
AVMAX = 32dB
2nd Harmonic
2nd Harmonic
VG = +2V
VO = 1VPP
f = 20MHz
3rd Harmonic
10
0.1
1
100
100
1k
Frequency (MHz)
Resistance (W)
Figure 60.
Figure 61.
HARMONIC DISTORTION vs
OUTPUT VOLTAGE
HARMONIC DISTORTION vs
GAIN CONTROL VOLTAGE
-10
-15
-20
-25
-30
-35
-40
-45
-50
-55
-60
-10
-20
-30
-40
-50
-60
-70
-80
AVMAX = 32dB
AVMAX = 32dB
VG = +2V
RL = 100W
f = 20MHz
VO = 2VPP
Maximum Current
RL = 100W
Through RG Limited
f = 20MHz
Maximum Current Through RG Limited
2nd Harmonic
3rd Harmonic
2nd Harmonic
3rd Harmonic
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0.1
1
Output Voltage Swing (VPP
10
Gain Control Voltage (V)
)
Figure 62.
Figure 63.
TWO-TONE, 3RD-ORDER INTERMODULATION INTERCEPT
vs
GAIN CONTROL VOLTAGE
35
TWO-TONE, 3RD-ORDER
INTERMODULATION INTERCEPT
34
32
30
28
26
24
22
Constant Output Voltage
30
Constant Input Voltage
25
20
15
VG = +2V
At 50W Matched Load
f = 20MHz
At 50W Matched Load
10
0
10
20
30
40 50
60 70
80
90 100
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Frequency (MHz)
Gain Control Voltage (V)
Figure 64.
Figure 65.
16
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 32dB (continued)
At TA = +25°C, RL = 100Ω, RF = 402Ω, RG = 18Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14
package, unless otherwise noted.
GAIN vs GAIN CONTROL VOLTAGE
GAIN CONTROL FREQUENCY RESPONSE
45
40
35
30
25
20
15
10
5
3
0
-3
-6
-9
-12
-15
-18
VG = 1VDC + 10mVPP
VIN = 10mVDC
0
-5
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain Control Voltage (V)
1M
10M
100M
Frequency (Hz)
1G
Figure 66.
Figure 67.
GAIN CONTROL PULSE RESPONSE
FULLY ATTENUATED RESPONSE
30
20
4
VIN = 50mVDC
3
VG = +2V
10
2
0
1
-10
-20
-30
-40
-50
-60
-70
-80
-90
VO = 2VPP
2.5
2.0
1.5
1.0
0.5
0
0
-1
Input Referred
VG = 0V
-0.5
1M
10M
100M
1G
Time (10ns/div)
Frequency (Hz)
Figure 68.
Figure 69.
IRG LIMITED OVERDRIVE RECOVERY
OUTPUT LIMITED OVERDRIVE RECOVERY
0.4
0.3
0.2
0.1
0
0.3
1.6
6
AVMAX = 32dB
Input Voltage
VG = 0.7V
AVMAX = 32dB
1.2
VG = +2V
Output Voltage
Left Scale
0.2
0.1
4
Right Scale
0.8
2
0.4
0
0
0
-0.1
-0.4
-0.8
-1.2
-1.6
-0.1
-0.2
-0.3
-2
-4
-6
-0.2
-0.3
-0.4
Input Voltage
Left Scale
Output Voltage
Right Scale
Time (40ns/div)
Time (40ns/div)
Figure 70.
Figure 71.
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
17
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 32dB (continued)
At TA = +25°C, RL = 100Ω, RF = 402Ω, RG = 18Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14
package, unless otherwise noted.
GROUP DELAY vs
GAIN CONTROL VOLTAGE
GROUP DELAY vs FREQUENCY
2.5
2.0
1.5
1.0
0.5
0
2.15
2.10
2.05
2.00
1.95
1.90
1.85
1.80
10MHz
20MHz
1MHz
VG = +2V
VO = 1VPP
0
20
40
60
80
100
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gain Control Voltage (V)
Frequency (MHz)
Figure 72.
Figure 73.
18
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
APPLICATION INFORMATION
WIDEBAND VARIABLE GAIN AMPLIFIER
OPERATION
For test purposes, the input impedance is set to 50Ω
with a resistor to ground and the output impedance is
set to 50Ω with a series output resistor. Voltage
swings reported in the Electrical Characteristics table
are taken directly at the input and output pins, while
output power (dBm) is at the matched 50Ω load. For
the circuit in Figure 74, the total effective load is
100Ω 1kΩ. Note that for the SO-14 package, there
is a voltage reference pin, VREF (pin 9). For the
SO-14 package, this pin must be connected to
ground through a 20Ω resistor in order to avoid
possible oscillations of the output stage. In the
MSOP-10 package, this pin is internally connected
and does not require such precaution. An X2Y™
capacitor has been used for power-supply bypassing.
The combination of low inductance, high resonance
frequency, and integration of three capacitors in one
package (two capacitors to ground and one across
the supplies) enables the VCA821 to achieve the low
second-harmonic distortion reported in the Electrical
Characteristics table. More information on how the
VCA821 operates can be found in the Operating
Suggestions section.
The VCA821 provides an exceptional combination of
high output power capability with a wideband, greater
than 40dB gain adjust range, linear in dB variable
gain amplifier. The VCA821 input stage places the
transconductance element between two input buffers,
using the output currents as the forward signal. As
the differential input voltage rises, a signal current is
generated through the gain element. This current is
then mirrored and gained by a factor of two before
reaching the multiplier. The other input of the
multiplier is the voltage gain control pin, VG.
Depending on the voltage present on VG, up to two
times the gain current is provided to the
transimpedance output stage. The transimpedance
output stage is a current-feedback amplifier providing
high output current capability and high slew rate,
2500V/µs. This exceptional full-power performance
comes at the price of relatively high quiescent current
(34mA), but low input voltage noise for this type of
architecture (6nV/√Hz).
Figure 74 shows the dc-coupled, gain of +10V/V, dual
power-supply circuit used as the basis of the ±5V
Electrical Characteristics and Typical Characteristics.
®
X2Y Capacitor Detail
0.1mF
X2Yâ
Capacitor
+VS
(see detail)
+5V
-5V
A
G1
G2
+
2.2mF
2.2mF
+
VG
B
-VS
+VIN
VIN
20W
x1
FB
IRG
RG+
RF
RG
1kW
x2
200W
RG-
VOUT
VOUT
x1
SO-14
VCA821
-VIN
VREF
20W
20W
Figure 74. DC-Coupled, AVMAX = 20dB, Bipolar Supply Specification and Test Circuit
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
19
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
DIFFERENCE AMPLIFIER
be used advantageously because its architecture
allows the application to isolate the input from the
gain setting elements. Figure 77 shows an
implementation of such a configuration. The transfer
function is shown in Equation 1.
Because both inputs of the VCA821 are
high-impedance,
a
difference amplifier can be
implemented without any major problem. Figure 75
shows this implementation. This circuit provides
excellent common-mode rejection ratio (CMRR) as
long as the input is within the CMRR range of –2.1V
to +1.6V. Note that this circuit does not make use of
the gain control pin, VG. Also, it is recommended to
choose RS such that the pole formed by RS and the
parasitic input capacitance does not limit the
bandwidth of the circuit. Figure 76 shows the
common-mode rejection ratio for this circuit
implemented in a gain of 20dB for VG = +2V. Note
that because the gain control voltage is fixed and is
normally set to +2V, the feedback element can be
reduced in order to increase the bandwidth. When
reducing the feedback element, make sure that the
VCA821 is not limited by common-mode input
voltage, the current flowing through RG, or any other
limitation described in this data sheet.
RF
1 + sRGC1
´
G = 2 ´
RG
1 + sR1C1
(1)
RF
VIN1
+VIN
RG+
RS
FB
VCA821
R1
RG
C1
RG-
VIN2
-VIN
20W
RS
Figure 77. Differential Equalizer
RF
VIN+
+VIN
RG+
RS
FB
This transfer function has one pole, P1 (located at
RGC1), and one zero, Z1 (located at R1C1). When
equalizing an RC load, RL and CL, compensate the
pole added by the load located at RLCL with the zero
Z1. Knowing RL, CL, and RG allows the user to select
C1 as a first step and then calculate R1. Using
RL = 75Ω, CL = 100pF and wanting the VCA821 to
RG
VCA821
RG-
-VIN
VIN-
20W
RS
operate at a gain of +2V/V, which gives RF = RG
=
Figure 75. Difference Amplifier
453Ω, allows the user to select C1 = 15.5pF to ensure
a positive value for the resistor R1. With all these
values known, to achieve greater than 300MHz
bandwidth, R1 can be calculated to be 20Ω. Figure 78
shows the frequency response for both the initial,
unequalized frequency response and the resulting
equalized frequency response.
85
80
75
70
65
60
55
50
45
40
Input Referred
9
Equalized Frequency Response
6
3
0
Initial Frequency Response
-3
of the VCA821 with RC Load
-6
-9
10k
100k
1M
10M
100M
-12
-15
-18
-21
-24
Frequency (Hz)
Figure 76. Common-Mode Rejection Ratio
DIFFERENTIAL EQUALIZER
1M
10M
100M
1G
Frequency (Hz)
If the application requires frequency shaping (the
transition from one gain to another), the VCA821 can
Figure 78. Differential Equalization of an RC Load
20
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
DIFFERENTIAL CABLE EQUALIZER
AGC LOOP
A
differential cable equalizer can easily be
In the typical AGC loop shown in Figure 81, the
OPA695 follows the VCA821 to provide 40dB of
overall gain. The output of the OPA695 is rectified
and integrated by an OPA820 to control the gain of
the VCA821. when the output level exceeds the
reference voltage (VREF), the integrator ramps down
reducing the gain of the AGC loop. Conversely, if the
output is too small, the integrator ramps up increasing
the net gain and the output voltage.
implemented using the VCA821. An example of a
cable equalization for 100 feet of Belden cable 1694F
is illustrated in Figure 78, with Figure 79 showing the
result for this implementation. This implementation
has a maximum error of 0.2dB from dc to 70MHz.
Note that this implementation shows the cable
attenuation side-by-side with the equalization in the
same plot. For a given frequency, the equalization
function realized with the VCA821 matches the cable
attenuation. The circuit in Figure 80 is a driver circuit.
To implement a receiver circuit, the signal is received
differentially between the +VIN and –VIN inputs.
2.0
1.5
1.0
Cable Attenuation
0.5
VCA821 Equalization
0
-0.5
-1.0
1
10
Frequency (MHz)
100
Figure 79. Cable Attenuation versus Equalizer Gain
R2
453W
VIN
+VIN
RG+
R8
R10
50W
R18
R17
R21
R9
75W
VOUT
FB
13.6kW
6kW
3kW
432W
VOUT
VCA821
VREF
C7
300mF
GND
VG
75W Load
RG-
R1
20W
-VIN
C6
320mF
R5
50W
C5
VG = +1VDC
4pF
C9
10mF
Figure 80. Differential Cable Equalizer
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
21
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
1kW
VIN
+VIN
RG+
FB
50W
50W
200W
Out
50W
VCA821
VOUT
OPA695
VG
RG-
-VIN
50W
950W
100W
50W
0.1mF
1N4150
1kW
OPA820
VREF
Figure 81. AGC Loop
predict typical small-signal ac performance, transient
steps, dc performance, and noise under a wide
variety of operating conditions. The models include
the noise terms found in the electrical specifications
of the relevant product data sheet.
DESIGN-IN TOOLS
DEMONSTRATION BOARDS
Two printed circuit boards (PCBs) are available to
assist in the initial evaluation of circuit performance
using the VCA821 in its two package options. Both of
these are offered free of charge as unpopulated
PCBs, delivered with a user's guide. The summary
information for these fixtures is shown in Table 1.
OPERATING SUGGESTIONS
Operating the VCA821 optimally for
a specific
application requires trade-offs between bandwidth,
input dynamic range and the maximum input voltage,
the maximum gain of operation and gain, output
dynamic range and the maximum input voltage, the
package used, loading, and layout and bypass
recommendations. The Typical Characteristics have
been defined to cover as much ground as possible to
describe the VCA821 operation. There are four
sections in the Typical Characteristics:
Table 1. EVM Ordering Information
LITERATURE
BOARD PART
NUMBER
REQUEST
NUMBER
PRODUCT
VCA821ID
PACKAGE
SO-14
DEM-VCA-SO-1B
SBOU050
SBOU051
VCA821IDGS
MSOP-10
DEM-VCA-MSOP-1A
•
VS = ±5V DC Parameters and VS = ±5V DC and
Power-Supply Parameters, which include dc
operation and the intrinsic limitation of a VCA821
design
The demonstration fixtures can be requested at the
Texas Instruments web site (www.ti.com) through the
VCA821 product folder.
•
•
•
VS = ±5V, AVMAX = 6dB Gain of 6dB Operation
VS = ±5V, AVMAX = 20dB Gain of 20dB Operation
VS = ±5V, AVMAX = 32dB Gain of 32dB Operation
MACROMODELS AND APPLICATIONS
SUPPORT
Computer simulation of circuit performance using
SPICE is often useful when analyzing the
performance of analog circuits and systems. This
principle is particularly true for video and RF amplifier
circuits where parasitic capacitance and inductance
can play a major role in circuit performance. A SPICE
model for the VCA821 is available through the TI web
page. The applications group is also available for
design assistance. The models available from TI
Where the Typical Characteristics describe the actual
performance that can be achieved by using the
amplifier properly, the following sections describe in
detail the trade-offs needed to achieve this level of
performance.
22
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
PACKAGE CONSIDERATIONS
There are no differences between the packages in
the recommended values for the gain and feedback
resistors. However, the bandwidth for the
VCA821IDGS (MSOP-10 package) is lower than the
bandwidth for the VCA821ID (SO-14 package). This
difference is true for all gains, but especially true for
gains greater than 5V/V, as can be seen in Figure 83
and Figure 84. Note that the scale must be changed
to a linear scale to view the details.
The VCA821 is available in both SO-14 and
MSOP-10 packages. Each package has, for the
different gains used in the typical characteristics,
different values of RF and RG in order to achieve the
same performance detailed in the Electrical
Characteristics table.
Figure 82 shows a test gain circuit for the VCA821.
Table 2 lists the recommended configuration for the
SO-14 and MSOP-10 packages.
3
AVMAX = 2V/V
0
AVMAX = 5V/V
+VIN
-3
VIN
RF
R1
RG+
-6
50W
50W
Source
RG
VOUT
-9
AVMAX = 10V/V
RG-
50W
-12
Load
R3
AVMAX = 20V/V
-VIN
-15
R2
AVMAX = 40V/V
50W
-18
0
200
400
600
800
1000
Frequency (MHz)
VG
Figure 83. SO-14 Recommended RF and RG
versus AVMAX
Figure 82. Test Circuit
Table 2. SO-14 and MSOP-10 RF and RG
Configurations
3
AVMAX = 2V/V
0
G = 2
453Ω
453Ω
G = 10
402Ω
80Ω
G = 40
AVMAX = 5V/V
-3
RF
402Ω
18Ω
RG
-6
-9
AVMAX = 10V/V
-12
AVMAX = 20V/V
-15
AVMAX = 40V/V
-18
0
200
400
600
800
1000
Frequency (MHz)
Figure 84. MSOP-10 Recommended RF and RG
versus AVMAX
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
23
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
MAXIMUM GAIN OF OPERATION
VCA821 can drive ±2.5V into 25Ω or ±3.5V into 50Ω
without exceeding the output capabilities or the 1W
dissipation limit. A 100Ω load line (the standard test
circuit load) shows the full ±3.9V output swing
capability, as shown in the Typical Characteristics.
This section describes the use of the VCA821 in a
fixed-gain application in which the VG control pin is
set at VG = +1V. The tradeoffs described here are
with bandwidth, gain, and output voltage range.
The minimum specified output voltage and current
over-temperature are set by worst-case simulations at
the cold temperature extreme. Only at cold startup do
the output current and voltage decrease to the
numbers shown in the Electrical Characteristics
tables. As the output transistors deliver power, the
respective junction temperatures increase, thereby
increasing the available output voltage swing and
output current.
In the case of an application that does not make use
of the VGAIN, but requires some other characteristic of
the VCA821, the RG resistor must be set such that
the maximum current flowing through the resistance
IRG is less than ±2.6mA typical, or 5.2mAPP as
defined in the Electrical Characteristics table, and
must follow Equation 2.
VOUT
IRG
=
AVMAX ´ RG
(2)
In steady-state operation, the available output voltage
and current are always greater than the temperature
shown in the over-temperature specifications
because the output stage junction temperatures are
higher than the specified operating ambient.
As Equation 2 illustrates, once the output dynamic
range and maximum gain are defined, the gain
resistor is set. This gain setting in turn affects the
bandwidth, because in order to achieve the gain (and
with a set gain element), the feedback element of the
output stage amplifier is set as well. Keeping in mind
INPUT VOLTAGE DYNAMIC RANGE
that the output amplifier of the VCA821 is
a
The VCA821 has a input dynamic range limited to
+1.6V and –2.1V. Increasing the input voltage
dynamic range can be done by using an attenuator
network on the input. If the VCA821 is trying to
regulate the amplitude at the output, such as in an
AGC application, the input voltage dynamic range is
directly proportional to Equation 3.
current-feedback amplifier, the larger the feedback
element, the lower the bandwidth because the
feedback resistor is the compensation element.
Limiting the discussion to the input voltage only and
ignoring the output voltage and gain, Figure 1
illustrates the tradeoff between the input voltage and
the current flowing through the gain resistor.
VIN(PP) = RG ´ IRG(PP)
(3)
As such, for unity-gain or under-attenuated
conditions, the input voltage must be limited to the
CMIR of ±1.6V (3.2VPP) and the current (IRQ) must
flow through the gain resistor, ±2.6mA (5.2mAPP).
This configuration sets a minimum value for RE such
that the gain resistor must be greater than
Equation 4.
OUTPUT CURRENT AND VOLTAGE
The VCA821 provides output voltage and current
capabilities that are unsurpassed in a low-cost
monolithic VCA. Under no-load conditions at +25°C,
the output voltage typically swings closer than 1V to
either supply rails; the +25°C swing limit is within
1.2V of either rails. Into a 15Ω load (the minimum
tested load), it is tested to deliver more than ±90mA.
3.2VPP
RGMIN
=
= 615.4W
5.2mAPP
(4)
The specifications described above, though familiar in
the industry, consider voltage and current limits
separately. In many applications, it is the voltage ×
current, or V-I product, that is more relevant to circuit
operation. Refer to the Output Voltage and Current
Limitations plot (Figure 48) in the Typical
Characteristics. The X- and Y-axes of this graph
show the zero-voltage output current limit and the
zero-current output voltage limit, respectively. The
four quadrants give a more detailed view of the
VCA821 output drive capabilities, noting that the
graph is bounded by a Safe Operating Area of 1W
maximum internal power dissipation. Superimposing
resistor load lines onto the plot shows that the
Values lower than 615.4Ω are gain elements that
result in reduced input range, as the dynamic input
range is limited by the current flowing through the
gain resistor RG (IRG). If the IRG current limits the
performance of the circuit, the input stage of the
VCA821 goes into overdrive, resulting in limited
output voltage range. Such IRG-limited overdrive
conditions are shown in Figure 50 for the gain of
20dB and Figure 70 for the 32dB gain.
24
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
OUTPUT VOLTAGE DYNAMIC RANGE
OFFSET ADJUSTMENT
With its large output current capability and its wide
output voltage swing of ±3.9V typical on 100Ω load, it
is easy to forget other types of limitations that the
VCA821 can encounter. For these limitations, careful
analysis must be done to avoid input stage limitation:
either voltage or IRG current. Note that if control pin
VG varies, the gain limitation may affect other aspects
of the circuit.
As a result of the internal architecture used on the
VCA821, the output offset voltage originates from the
output stage and from the input stage and multiplier
core. Figure 85 shows how to compensate both
sources of the output offset voltage. Use this
procedure to compensate the output offset voltage:
starting with the output stage compensation, set
VG = –1V to eliminate all offset contribution of the
input stage and multiplier core. Adjust the output
stage offset compensation potentiometer. Finally, set
VG = +1V to the maximum gain and adjust the input
stage and multiplier core potentiometer. This
procedure effectively eliminates all offset contribution
at the maximum gain. Because adjusting the gain
modifies the contribution of the input stage and the
multiplier core, some residual output offset voltage
remains.
BANDWIDTH
The output stage of the VCA821 is a wideband
current-feedback amplifier. As such, the feedback
resistance is the compensation of the last stage.
Reducing the feedback element and maintaining the
gain constant limits the useful range of IRG, and
therefore, reduces the gain adjust range. For a given
gain, reducing the gain element limits the maximum
achievable output voltage swing.
+5V
Output Stage Offset
Compensation Circuit
10kW
0.1mF
4kW
-5V
RF
VIN
+VIN
RG+
50W
FB
RG
VOUT
VCA821
RG-
-VIN
+5V
50W
1kW
10kW
0.1mF
Input Stage and Multiplexer Core
Offset Compensation Circuit
-5V
Figure 85. Adjusting the Input and Output Voltage Sources
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
25
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
NOISE
This model is formulated in Equation 5 and Figure 86.
eO = AVMAX
2 ´ (RS ´ in)2 + en2 + 2 ´ 4kTRS
The VCA821 offers 6nV/√Hz input-referred voltage
noise density at a gain of 20dB and 2.6pA/√Hz
´
(5)
input-referred
current
noise
density.
The
A more complete model is shown in Figure 87. For
additional information on this model and the actual
modeled noise terms, please contact the High-Speed
Product Application Support team at www.ti.com.
input-referred voltage noise density considers that all
noise terms (except the input current noise but
including the thermal noise of both the feedback
resistor and the gain resistor) are expressed as one
term.
RF
+VIN
RG+
FB
in
RS
eO
RG
eO
VCA821
RG-
*
4kTRS
in
-VIN
RS
4kTRS
*
NOTE: RF and RG are noiseless.
Figure 86. Simple Noise Model
VG
VG
inINPUT
+VIN
V+
RS1
enINPUT
*
4kTRS1
*
FB
x1
RF
inINPUT
*
4kTRF
+RG
*
VOUT
eO
RG
(Noiseless)
ICORE
iinOUTPUT
-RG
VREF
x1
RF
enOUTPUT
iniOUTPUT
enINPUT
4kTRF
*
*
-VIN
V-
RS2
inINPUT
GND
4kTRS2
*
Figure 87. Full Noise Model
26
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
THERMAL ANALYSIS
band limiting. To reduce unwanted capacitance, a
window around the signal I/O pins should be opened
in all of the ground and power planes around those
pins. Otherwise, ground and power planes should be
unbroken elsewhere on the board. Place a small
series resistance (greater than 25Ω) with the input pin
connected to ground to help decouple package
parasitics.
The VCA821 does not require heatsinking or airflow
in most applications. The maximum desired junction
temperature sets the maximum allowed internal
power dissipation as described in this section. In no
case should the maximum junction temperature be
allowed to exceed +150°C.
Operating junction temperature (TJ) is given by
Equation 6:
TJ = TA + PD ´ qJA
b) Minimize the distance (less than 0.25 inches, or
6.3mm) from the power-supply pins to high-frequency
0.1µF decoupling capacitors. At the device pins, the
ground and power plane layout should not be in close
proximity to the signal I/O pins. Avoid narrow power
and ground traces to minimize inductance between
the pins and the decoupling capacitors. The
power-supply connections should always be
decoupled with these capacitors. Larger (2.2µF to
6.8µF) decoupling capacitors, effective at lower
frequencies, should also be used on the main supply
pins. These capacitors may be placed somewhat
farther from the device and may be shared among
several devices in the same area of the PCB.
(6)
The total internal power dissipation (PD) is the sum of
quiescent power (PDQ
)
and additional power
dissipated in the output stage (PDL) to deliver load
power. Quiescent power is simply the specified
no-load supply current times the total supply voltage
across the part. PDL depends on the required output
signal and load; for a grounded resistive load,
however, it is at a maximum when the output is fixed
at a voltage equal to one-half of either supply voltage
(for equal bipolar supplies). Under this worst-case
2
condition, PDL = VS /(4 × RL), where RL is the
resistive load.
c) Careful selection and placement of external
components
preserve
the
high-frequency
Note that it is the power in the output stage and not in
the load that determines internal power dissipation.
As a worst-case example, compute the maximum TJ
using a VCA821ID (SO-14 package) in the circuit of
Figure 74 operating at maximum gain and at the
maximum specified ambient temperature of +85°C.
performance of the VCA821. Resistors should be a
very low reactance type. Surface-mount resistors
work best and allow a tighter overall layout. Metal-film
and carbon composition, axially-leaded resistors can
also provide good high-frequency performance.
Again, keep the leads and PCB trace length as short
as possible. Never use wire-wound type resistors in a
high-frequency application. Because the output pin is
the most sensitive to parasitic capacitance, always
position the series output resistor, if any, as close as
possible to the output pin. Other network
components, such as inverting or non-inverting input
termination resistors, should also be placed close to
the package.
PD = 10V(36mA) + 52/(4 ´ 100W) = 422.5mW
(7)
Maximum TJ = +85°C + (0.443W ´ 80°C/W) = 120.5°C
(8)
This maximum operating junction temperature is well
below most system level targets. Most applications
should be lower because an absolute worst-case
output stage power was assumed in this calculation
of VCC/2, which is beyond the output voltage range for
the VCA821.
d) Connections to other wideband devices on the
board may be made with short direct traces or
through onboard transmission lines. For short
connections, consider the trace and the input to the
next device as a lumped capacitive load. Relatively
wide traces (50mils to 100mils, or 1.27mm to
2.54mm) should be used, preferably with ground and
power planes opened up around them.
BOARD LAYOUT
Achieving
optimum
performance
with
a
high-frequency amplifier such as the VCA821
requires careful attention to printed circuit board
(PCB) layout parasitics and external component
types. Recommendations to optimize performance
include:
e) Socketing a high-speed part like the VCA821 is
not recommended. The additional lead length and
pin-to-pin capacitance introduced by the socket can
create an extremely troublesome parasitic network,
which can make it almost impossible to achieve a
smooth, stable frequency response. Best results are
obtained by soldering the VCA821 onto the board.
a) Minimize parasitic capacitance to any ac ground
for all of the signal I/O pins. This recommendation
includes the ground pin (pin 2). Parasitic capacitance
on the output can cause instability: on both the
inverting input and the noninverting input, it can react
with the source impedance to cause unintentional
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
27
Product Folder Link(s): VCA821
VCA821
SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008....................................................................................................................................... www.ti.com
INPUT AND ESD PROTECTION
ESD protection diodes internally
+VS
connected to all pins.
The VCA821 is built using
a very high-speed
complementary bipolar process. The internal junction
breakdown voltages are relatively low for these very
small geometry devices. These breakdowns are
reflected in the Section 2 table.
External
Pin
Internal
Circuitry
All pins on the VCA821 are internally protected from
-VS
ESD by means of
a
pair of back-to-back
reverse-biased diodes to either power supply, as
shown in Figure 88. These diodes begin to conduct
when the pin voltage exceeds either power supply by
about 0.7V. This situation can occur with loss of the
amplifier power supplies while a signal source is still
Figure 88. Internal ESD Protection
present. The diodes can typically withstand
a
continuous current of 30mA without destruction. To
ensure long-term reliability, however, diode current
should be externally limited to 10mA whenever
possible.
28
Submit Documentation Feedback
Copyright © 2007–2008, Texas Instruments Incorporated
Product Folder Link(s): VCA821
VCA821
www.ti.com ....................................................................................................................................... SBOS407B–DECEMBER 2007–REVISED DECEMBER 2008
Revision History
Changes from Revision A (August 2008) to Revision B ................................................................................................ Page
•
Revised second paragraph in Wideband Variable Gain Amplifier Operation section describing pin 9............................... 19
Changes from Original (December 2007) to Revision A ................................................................................................ Page
•
Changed storage temperature range rating in Absolute Maximum Ratings table from –40°C to +125°C to –65°C to
+125°C................................................................................................................................................................................... 2
Copyright © 2007–2008, Texas Instruments Incorporated
Submit Documentation Feedback
29
Product Folder Link(s): VCA821
PACKAGE OPTION ADDENDUM
www.ti.com
17-May-2014
PACKAGING INFORMATION
Orderable Device
Status Package Type Package Pins Package
Eco Plan
Lead/Ball Finish
MSL Peak Temp
Op Temp (°C)
Device Marking
Samples
Drawing
Qty
(1)
(2)
(6)
(3)
(4/5)
VCA821ID
ACTIVE
SOIC
D
14
50
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
VCA821ID
VCA821IDG4
ACTIVE
ACTIVE
SOIC
D
14
10
TBD
Call TI
Call TI
-40 to 85
-40 to 85
VCA821IDGSR
VSSOP
DGS
2500
250
Green (RoHS
& no Sb/Br)
CU NIPDAU |
CU NIPDAUAG
Level-2-260C-1 YEAR
BOR
VCA821IDGSRG4
VCA821IDGST
ACTIVE
ACTIVE
VSSOP
VSSOP
DGS
DGS
10
10
TBD
Call TI
Call TI
-40 to 85
-40 to 85
Green (RoHS
& no Sb/Br)
CU NIPDAU |
CU NIPDAUAG
Level-2-260C-1 YEAR
BOR
VCA821IDGSTG4
VCA821IDR
ACTIVE
ACTIVE
VSSOP
SOIC
DGS
D
10
14
TBD
Call TI
Call TI
-40 to 85
-40 to 85
2500
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
VCA821ID
VCA821IDRG4
ACTIVE
SOIC
D
14
TBD
Call TI
Call TI
-40 to 85
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
17-May-2014
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
19-Nov-2012
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
B0
K0
P1
W
Pin1
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant
(mm) W1 (mm)
VCA821IDGSR
VCA821IDGST
VCA821IDR
VSSOP
VSSOP
SOIC
DGS
DGS
D
10
10
14
2500
250
330.0
180.0
330.0
12.4
12.4
16.4
5.3
5.3
6.5
3.4
3.4
9.0
1.4
1.4
2.1
8.0
8.0
8.0
12.0
12.0
16.0
Q1
Q1
Q1
2500
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
19-Nov-2012
*All dimensions are nominal
Device
Package Type Package Drawing Pins
SPQ
Length (mm) Width (mm) Height (mm)
VCA821IDGSR
VCA821IDGST
VCA821IDR
VSSOP
VSSOP
SOIC
DGS
DGS
D
10
10
14
2500
250
367.0
210.0
367.0
367.0
185.0
367.0
35.0
35.0
38.0
2500
Pack Materials-Page 2
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other
changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest
issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and
complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale
supplied at the time of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and
applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration
and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered
documentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which
anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use
of any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to
help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and
requirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in
military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and
regulatory requirements in connection with such use.
TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use of
non-designated products, TI will not be responsible for any failure to meet ISO/TS16949.
Products
Applications
Audio
www.ti.com/audio
amplifier.ti.com
dataconverter.ti.com
www.dlp.com
Automotive and Transportation www.ti.com/automotive
Communications and Telecom www.ti.com/communications
Amplifiers
Data Converters
DLP® Products
DSP
Computers and Peripherals
Consumer Electronics
Energy and Lighting
Industrial
www.ti.com/computers
www.ti.com/consumer-apps
www.ti.com/energy
dsp.ti.com
Clocks and Timers
Interface
www.ti.com/clocks
interface.ti.com
logic.ti.com
www.ti.com/industrial
www.ti.com/medical
Medical
Logic
Security
www.ti.com/security
Power Mgmt
Microcontrollers
RFID
power.ti.com
Space, Avionics and Defense
Video and Imaging
www.ti.com/space-avionics-defense
www.ti.com/video
microcontroller.ti.com
www.ti-rfid.com
www.ti.com/omap
OMAP Applications Processors
Wireless Connectivity
TI E2E Community
e2e.ti.com
www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2014, Texas Instruments Incorporated
相关型号:
VCA821IDGSR
Ultra-Wideband, > 40dB Gain Adjust Range, Linear in dB VARIABLE GAIN AMPLIFIERWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA821IDGSRG4
SPECIALTY ANALOG CIRCUIT, PDSO14, GREEN, PLASTIC, MSOP-10Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA821IDGST
Ultra-Wideband, > 40dB Gain Adjust Range, Linear in dB VARIABLE GAIN AMPLIFIERWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA821IDGSTG4
SPECIALTY ANALOG CIRCUIT, PDSO14, GREEN, PLASTIC, MSOP-10Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA821IDR
Ultra-Wideband, > 40dB Gain Adjust Range, Linear in dB VARIABLE GAIN AMPLIFIERWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA821IDRG4
SPECIALTY ANALOG CIRCUIT, PDSO14, GREEN, PLASTIC, MS-012AB, SOIC-14Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA821_12
Ultra-Wideband, > 40dB Gain Adjust Range, Linear in dB VARIABLE GAIN AMPLIFIERWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA822
Wideband, > 40dB Gain Adjust Range, Linear in V/V VARIABLE GAIN AMPLIFIERWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA822ID
Wideband, > 40dB Gain Adjust Range, Linear in V/V VARIABLE GAIN AMPLIFIERWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA822IDG4
Wideband, > 40dB Gain Adjust Range, Linear in V/V VARIABLE GAIN AMPLIFIERWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA822IDGS
Wideband, > 40dB Gain Adjust Range, Linear in V/V VARIABLE GAIN AMPLIFIERWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
VCA822IDGSR
Wideband, > 40dB Gain Adjust Range, Linear in V/V VARIABLE GAIN AMPLIFIERWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
TI
©2020 ICPDF网 联系我们和版权申明