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FEATURES
GAIN RANGE: 50dB
LOW CROSSTALK: 60dB at Max Gain, fIN = 5MHz
HIGH−SPEED VARIABLE GAIN ADJUST
POWER SHUTDOWN MODE
HIGH IMPEDANCE INPUT BUFFER
APPLICATIONS
ULTRASOUND SYSTEMS
WIRELESS RECEIVERS
TEST EQUIPMENT
RADAR
DESCRIPTION
The VCA2619 is a highly integrated, dual receive channel,Variable Gain Amplifier (VGA) with analog gain control.
The VCA2619s VGA section consists of two parts: theVoltage Controlled Attenuator (VCA) and the ProgrammableGain Amplifier (PGA). The gain and gain range of the PGAcan be digitally programmed. The combination of these twoprogrammable elements results in a variable gain rangingfrom 0dB up to a maximum gain as defined by the userthrough external connections. The single−ended unity gaininput buffer provides predictable high input impedance. Theoutput of the VGA can be used in either a single−ended ordifferential mode to drive high−performance Analog−to−Digital (A/D) converters. A separate power−down pinreduces power consumption.
The VCA2619 also features low crosstalk and outstandingdistortion performance. The combination of low noise andgain range programmability make the VCA2619 a versatilebuilding block in a number of applications where noiseperformance is critical. The VCA2619 is available in aTQFP−32 package.
All trademarks are the property of their respective owners.
VCA2619
SBOS276A − AUGUST 2003 − REVISED AUGUST 2003
Dual, Variable Gain Amplifierwith Input Buffer
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Copyright 2003, Texas Instruments Incorporated
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instrumentssemiconductor products and disclaimers thereto appears at the end of this data sheet.
! !
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ABSOLUTE MAXIMUM RATINGS (1)
Power Supply (+VS) +6V
Analog Input −0.3V to (+VS + 0.3V)
Logic Input −0.3V to (+VS + 0.3V)
Case Temperature +100°C
Junction Temperature +150°C
Storage Temperature −40°C to +150°C(1) Stresses above those listed under “Absolute Maximum Ratings”
may cause permanent damage to the device. Exposure toabsolute maximum conditions for extended periods may affectdevice reliability.
This integrated circuit can be damaged by ESD.Texas Instruments recommends that allintegrated circuits be handled with appropriate
precautions. Failure to observe proper handling andinstallation procedures can cause damage.
ESD damage can range from subtle performance degradationto complete device failure. Precision integrated circuits maybe more susceptible to damage because very smallparametric changes could cause the device not to meet itspublished specifications.
PACKAGE/ORDERING INFORMATION
PRODUCT PACKAGE-LEADPACKAGE
DESIGNATOR(1)
SPECIFIEDTEMPERATURE
RANGE
PACKAGEMARKING ORDERING NUMBER
TRANSPORT MEDIA,QUANTITY
VCA2619Y TQFP−32 PBS −40°C to +85°C VCA2619YVCA2619YT Tape and Reel, 250
VCA2619Y TQFP−32 PBS −40°C to +85°C VCA2619YVCA2619YR Tape and Reel, 2000
(1) For the most current specification and package information, refer to our web site at www.ti.com.
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ELECTRICAL CHARACTERISTICS At TA = +25°C, VDD = 5V, load resistance = 500Ω on each output to ground single−ended output (1Vpp), MGS = 111, VCACNTL = 2.9V and
fIN = 5MHz, unless otherwise noted.
VCA2619
PARAMETER CONDITIONS MIN TYP MAX UNIT
BUFFER
Input Resistance 600 kΩ
Input Capacitance 5 pF
Input Bias Current 1 nA
Maximum Input Voltage 1 VppInput Voltage Noise PGA Gain = 45dB, RS = 50Ω 5.9 nV/√HzInput Current Noise Independent of Gain 350 fA/√HzNoise Figure RF = 550Ω, PGA Gain = 45dB, RS = 75Ω 13 dBBandwidth 100 MHz
PROGRAMMABLE VARIABLE GAIN AMPLIFIER
Peak Input Voltage 1 Vpp
−3dB Bandwidth 20 MHz
Slew Rate 300 V/µs
Output Signal Range RL ≥ 500Ω Each Side to Ground 2.5 ±1 V
Output Impedance 1 Ω
Output Short−Circuit Current ±40 mA
3rd-Harmonic Distortion VOUT = 1Vpp, VCACNTL = 2.9V −45 −60 dBc
2nd-Harmonic Distortion VOUT = 1Vpp, VCACNTL = 2.9V −42 −50 dBc
2nd-Harmonic Distortion Differential, VOUT = 2Vpp, VCACNTL = 3.0V, MGS = 011 −50 dBc
Overload Performance (2nd-Harmonic Distortion) Input Signal = 0.5Vpp, VCACNTL = 2V −40 to −45 dB
Time Delay 5 ns
IMD, 2−Tone VOUT = 2Vpp, f = 9.95MHz −59 dBc
Crosstalk 2Vpp Differential −60 dB
ACCURACY
Gain Slope VCACNTL = 0.4V to 2.9V 20 dB/VGain Error(1)
Output Offset VoltageGain Range
VCACNTL = 0.2V to 3.0VVCACNTL = 0.4V to 2.9V
VCACNTL = 0.2V to 3.0VVCACNTL = 0.4V to 2.9V 48
±2.75±1.50±505250
±2.0dBdBmVdBdB
GAIN CONTROL INTERFACE
Input Voltage (VCACNTL) Range 0 to 3.0 V
Input ResistanceResponse Time
1 MΩInput ResistanceResponse Time 45dB Gain Change 0.2 µs
POWER SUPPLY
Specified Operating Range 4.75 5.0 5.25 VPower Dissipation 240 300 mWPower−Down 9.2 mW
(1) Referenced to best fit dB−linear curve.
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PIN CONFIGURATION
+INA
NC
VDDR
VBIAS
VCM
GNDR
NC
+INB
VCACNTL
MGS3
MGS2
MGS1
PD
NC
NC
DNC
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
VCA2619
32 31 30 29 28 27 26 25
9 10 11 12 13 14 15 16
NC
NC
CP2
B
CP1
B
VD
DB
GN
DB
PO
UTB
NO
UTB
NC
NC
CP
2A
CP
1A
VD
DA
GN
DA
PO
UTA
NO
UTA
PIN CONFIGURATIONPIN DESIGNATOR DESCRIPTION PIN DESIGNATOR DESCRIPTION
1 +INA Noninverting Input Channel A 17 DNC Do Not Connect
2 NC No Internal Connection 18 NC No Internal Connection
3 VDDR Internal Reference Supply 19 NC No Internal Connection
4 VBIAS Bias Voltage 20 PD Power-Down (Active LOW)
5 VCM Common−Mode Voltage 23 MGS1 Maximum Gain Select 1 (MSB)
6 GNDR Internal Reference Ground 22 MGS2 Maximum Gain Select 2
7 NC No Internal Connection 23 MGS3 Maximum Gain Select 3 (LSB)
8 +INB Noninverting Input Channel B 24 VCACNTL VCA Analog Control
9 NC No Internal Connection 25 NOUTA Negative VCA Output Channel A
10 NC No Internal Connection 26 POUTA Positive VCA Output Channel A
11 CP2B Coupling Capacitor Channel B 27 GNDA Ground Channel A
12 CP1B Coupling Capacitor Channel B 28 VDDA +5V Supply Channel A
13 VDDB +5V Supply Channel B 29 CP1A Coupling Capacitor Channel A
14 GNDB Ground Channel B 30 CP2A Coupling Capacitor Channel A
15 POUTB Positive Output Channel B 31 NC No Internal Connection
16 NOUTB Negative Output Channel B 32 NC No Internal Connection
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TYPICAL CHARACTERISTICS
At TA = 25°C and VDD = 5V, load resistance = 500Ω on each output to ground, differential output (2VPP) MGS = 111, and fIN = 5MHz, unlessotherwise noted.
GAIN vs VCA
VCACNTL (V)
0.2 1.0 1.20.80.4 0.6 2.0 2.21.4 1.6 1.8 2.4 2.6 2.8 3.0
Gai
n(d
B)
4642383430262218141062
−2−6
−10−14
MGS = 111
MGS = 010
MGS = 100
MGS = 011
MGS = 110
MGS = 101
GAIN ERROR vs VCACNTL
VCACNTL (V)
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
Ga
inE
rror
(dB
)
3.0
2.5
2.0
1.5
1.0
0.5
0
−0.5
−1.0
−1.5
−2.0
−2.5
−3.0
10MHz
5MHz 1MHz
GAIN MATCH: CHA to CHB, VCACNTL = 0.4V
Delta Gain (dB)
Un
its
− 0.9
9− 0
.91
− 0.8
3− 0
.75
− 0.6
7− 0
.59
− 0.5
1− 0
.42
− 0.3
4− 0
.26
− 0.1
8− 0
.10
− 0.0
20
.06
0.1
40
.22
0.3
00
.38
0.4
7M
ore
45
40
35
30
25
20
15
10
5
0
GAIN ERROR vs TEMPERATURE
VCACNTL (V)
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
Gai
nE
rror
(dB
)
3.0
2.5
2.0
1.5
1.0
0.5
0−0.5
−1.0
−1.5
−2.0
−2.5
−3.0
+25C
−40C
+85C
GAIN ERROR vs VCACNTL
VCACNTL (V)
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
Ga
inE
rror
(dB
)3.0
2.5
2.0
1.5
1.0
0.5
0
−0.5
−1.0
−1.5
−2.0−2.5
−3.0
MGS = 010
MGS = 100
MGS = 111
GAIN MATCH: CHA to CHB, VCACNTL = 2.9V
Delta Gain (dB)
Uni
ts
− 0.1
6− 0
.14
− 0.1
3− 0
.11
− 0.0
9− 0
.08
− 0.0
6− 0
.04
− 0.0
3− 0
.01
0.01
0.02
0.04
0.06
0.07
0.09
0.11
0.12
0.14
Mor
e
45
40
35
30
25
20
15
10
5
0
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TYPICAL CHARACTERISTICS (continued)
At TA = 25°C and VDD = 5V, load resistance = 500Ω on each output to ground, differential output (2VPP) MGS = 111, and fIN = 5MHz, unlessotherwise noted.
GAIN vs FREQUENCY(VCACNTL = 2.9V)
Frequency (MHz)
100k 1M 10M 100M
Gai
n(d
B)
50
45
40
35
30
25
20
15
10
5
0
MGS = 111
MGS = 100
MGS = 010
OUTPUT REFERRED NOISE vs VCACNTL
VCACNTL (V)
0.2 1.0 1.20.4 0.6 0.8 1.8 2.01.4 1.6 2.2 2.4 2.6 2.8 3.0
Noi
se(n
V/√
Hz)
1100
1000
900
800
700
600
500
400
300
200
100
0
MGS = 111
MGS = 100
RS= 50Ω
INPUT REFERRED NOISE vs RS
RS (Ω )
1 10 100 1k
Noi
se(n
V√ H
z)
100
10
1
GAIN vs FREQUENCY(MGS = 111)
Frequency (MHz)
100k 1M 10M 100M
Ga
in(d
B)
50
40
30
20
10
0
−10
−20
VCACNTL = 2.9V
VCACNTL = 1.9V
VCACNTL = 0.9V
INPUT REFERRED NOISE vs VCACNTL
VCACNTL (V)
0.2 1.0 1.20.4 0.6 0.8 1.8 2.01.4 1.6 2.2 2.4 2.6 2.8 3.0
Noi
se(n
V/√
Hz)
150014001300120011001000900800700600500400300200100
0
MGS = 111
MGS = 100
RS= 50Ω
NOISE FIGURE vs RS
10 100 1k
Noi
seF
igur
e(d
B)
191817161514131211109876543210
RS (Ω)
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TYPICAL CHARACTERISTICS (continued)
At TA = 25°C and VDD = 5V, load resistance = 500Ω on each output to ground, differential output (2VPP) MGS = 111, and fIN = 5MHz, unlessotherwise noted.
NOISE FIGURE vs VCACNTL
VCACNTL (V)
Noi
seF
igu
re(d
B)
7065605550454035302520151050
0.2 1.0 1.20.4 0.6 0.8 1.8 2.01.4 1.6 2.2 2.4 2.6 2.8 3.0
HARMONIC DISTORTION vs FREQUENCY(Differential, 2VPP, MGS = 100)
Frequency (Hz)
100k 1M 10M
Har
mon
icD
isto
rtio
n(d
Bc)
−30
−35−40−45
−50
−55−60
−65−70−75
−80−85
−90
VCACNTL = 0.9V, H2
VCACNTL = 0.9V, H3VCACNTL = 2.9V, H2VCACNTL = 2.9V, H3
HARMONIC DISTORTION vs FREQUENCY(Single−Ended, 1VPP, MGS = 010)
Frequency (Hz)
100k 1M 10M
Har
mon
icD
isto
rtio
n(d
Bc)
−30
−35
−40−45
−50−55−60
−65−70
−75
−80
−85−90
VCACNTL = 0.9V, H2
VCACNTL = 0.9V, H3VCACNTL = 2.9V, H2VCACNTL = 2.9V, H3
HARMONIC DISTORTION vs FREQUENCY(Differential, 2VPP, MGS = 010)
Frequency (Hz)
100k 1M 10M
Har
mo
nic
Dis
tort
ion
(dB
c)
−30
−35
−40
−45
−50
−55
−60
−65
−70
VCACNTL = 0.9V, H2
VCACNTL = 0.9V, H3VCACNTL = 2.9V, H2VCACNTL = 2.9V, H3
HARMONIC DISTORTION vs FREQUENCY(Differential, 2VPP, MGS = 111)
Frequency (Hz)
100k 1M 10M
Har
mon
icD
isto
rtio
n(d
Bc)
−30
−35
−40
−45
−50
−55
−60
−65
−70
−75
−80
VCAC NTL = 0.9V, H2
VCAC NTL = 0.9V, H3
VCAC NTL = 2.9V, H2VCAC NTL = 2.9V, H3
HARMONIC DISTORTION vs FREQUENCY(Single−Ended, 1VPP, MGS = 100)
Frequency (Hz)
100k 1M 10M
Ha
rmo
nic
Dis
tort
ion
(dB
c)
−30−35
−40−45−50
−55−60
−65
−70−75−80
−85
−90
VCACNTL = 0.9V, H2
VCACNTL = 0.9V, H3VCACNTL = 2.9V, H2VCACNTL = 2.9V, H3
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TYPICAL CHARACTERISTICS (continued)
At TA = 25°C and VDD = 5V, load resistance = 500Ω on each output to ground, differential output (2VPP) MGS = 111, and fIN = 5MHz, unlessotherwise noted.
HARMONIC DISTORTION vs FREQUENCY(Single−Ended, 1VPP, MGS = 111)
Frequency (Hz)
100k 1M 10M
Har
mo
nic
Dis
tort
ion
(dB
c)
−30−35−40
−45
−50−55
−60−65−70
−75−80
−85
−90
VCACNTL = 0.9V, H2
VCACNTL = 0.9V, H3VCACNTL = 2.9V, H2VCACNTL = 2.9V, H3
HARMONIC DISTORTION vs VCACNTL(Single−Ended, 1VPP, 5MHz)
VCACNTL (V)
0.9 1.1 1.3 1.5 1.7 1.9 2.1 2.3 2.5 2.7 2.9
Ha
rmo
nic
Dis
tort
ion
(dB
c)
−30
−35
−40
−45
−50
−55
−60
−65
MGS = 010, H2MGS = 100, H2MGS = 111, H2MGS = 010, H3MGS = 100, H3MGS = 111, H3
INTERMODULATION DISTORTION(Differential, 2 VPP, fIN = 10MHz)
Frequency (MHz)
Am
plit
ude
(dB
)
10.110.0 10.2 10.3 10.4 10.59.99.89.79.69.5
0
−10
−20
−30
−40
−50
−60
−70
−80
−90
−100
HARMONIC DISTORTION vs VCACNTL(Differential, 2VPP, 5MHz)
VCACNTL (V)
0.9 1.1 1.3 1.5 1.7 1.9 2.1 2.3 2.5 2.7 2.9
Ha
rmon
icD
isto
rtio
n(d
Bc)
0−5
−10−15−20−25−30−35−40−45−50−55−60−65−70−75−80
MGS = 010, H2MGS = 100, H2MGS = 111, H2MGS = 010, H3MGS = 100, H3MGS = 111, H3
INTERMODULATION DISTORTION(Single−Ended, 1VPP, fIN = 10MHz)
Frequency (MHz)
Am
plit
ude
(dB
)
10.110.0 10.2 10.3 10.4 10.59.99.89.79.69.5
0
−10
−20
−30
−40
−50
−60
−70
−80
−90
−100
CROSS TALK vs FREQUENCY(Differential, 2VPP, MGS = 011)
Frequency (Hz)
Cro
ssT
alk
(dB
)
10M 20M1M
0
−10
−20
−30
−40
−50
−60
−70
VCACNTL = 0.9V
VCACNTL = 1.9V
VCACNTL = 2.9V
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TYPICAL CHARACTERISTICS (continued)
At TA = 25°C and VDD = 5V, load resistance = 500Ω on each output to ground, differential output (2VPP) MGS = 111, and fIN = 5MHz, unlessotherwise noted.
OVERLOAD DISTORTION vs FREQUENCY
Frequency (Hz)
1M 10M
2nd−
Ha
rmo
nic
Dis
tort
ion
(dB
c)
0
−10
−20
−30
−40
−50
−60
0.2V0.3V0.5V1V
55
54
53
52
51
50
49
48
47
46
45
ICC (CHA and CHB) vs TEMPERATURE
Temperature (C)
−40 −30 −20 −10 0 10 20 30 40 50 60 70 80 90
I CC
(mA
)OVERVIEWThe VCA2619 is a dual-channel, VGA consisting of threeprimary blocks: an Input Buffer, a VCA, and a PGA. Allstages are ac coupled, with the coupling into the PGAstage being made variable by placing an external capaci-tor between the CP1 and CP2 pins. This will be discussedfurther in the PGA section. By using the internal couplinginto the PGA, the result is a high-pass filter characteristicwith cutoff at approximately 75kHz. The output PGA natu-rally rolls off at around 30MHz, making the usable band-width of the VCA2619 between 75kHz and 30MHz.
VCABuffer
Buffer
Channel AInput
VCAControl
PGAChannel AOutput
MaximumGain
SelectMGS
AnalogControl
VCAChannel B
InputPGA
Channel BOutput
Figure 1. Simplified Block Diagram of theVCA2619.
INPUT BUFFER
The input buffer is a unity gain amplifier (gain of +1) witha bandwidth of 100MHz with an input resistance of approx-imately 600kΩ. The input buffer isolates the circuit drivingthe VCA2619 inputs from the internal VCA block, whichwould present a varying impedance to the input circuitry.To allow symmetrical operation of the input buffer, the inputto the buffer must be ac coupled through an external ca-pacitor. The recommended value of the capacitor is0.01µF. It should be noted that if the capacitor value wereincreased, the power-on time of the VCA2619 would be in-creased. If a decrease in the power-on time is needed, thevalue can be decreased to no less than 100pF.
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VOLTAGE-CONTROLLED ATTENUATORThe magnitude of the VCA input signal from the inputbuffer is reduced by a programmable attenuation factor,set by the analog VCA Control Voltage (VCACNTL) at pin24. The maximum attenuation is programmable by usingthe three MGS bits (pins 21, 22, and 23). Figure 2illustrates this dual-adjust characteristic.
0
−41
VC
AA
ttenu
atio
n(d
B)
−52.3
Control Voltage
0
Maximum Attenuation
Minimum Attenuation
3.0V
Figure 2. Swept Attenuator Characteristic.
The MGS bits adjust the overall range of attenuation andmaximum gain while the VCACNTL voltage adjusts theactual attenuation factor. Figure 3 is a simplified version ofthe voltage control attenuator. Figure 4 illustrates thepiecewise approximation to the logarithmic controlcharacteristics. At any given maximum gain setting, theanalog variable gain characteristic is linear in dB as afunction of the control voltage, and is created as apiecewise approximation of an ideal dB-linear transferfunction. The VCA control circuitry is common to bothchannels of the VCA2619. The range for the VCACNTLinput spans from 0V to 3V. Although overdriving theVCACNTL input above the recommended 3V maximum willnot damage the part, this condition should be avoided.
RS
Q1A
A1
B1
VCM
Input Output
B2
Q1B Q2A
A2
Q2B Q3A
A3
Q3B Q4A
A4
Q4B Q5A
A5
Q5B
Figure 3. Simplified Attenuator Diagram.
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RS
AttenuatorInput
AttenuatorOutput
A1 to A10Attenuator Stages
ControlInput
Q1VCM
0dB
−5.2dB
Q2 Q3
C1
V1
Q4 Q5
QS
C1 to C10Clipping Amplifiers
AttenuationCharacteristic of Individual FETs
Q6 Q7 Q8 Q9 Q10
C2
V2
VCM − VT
0
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
Characteristic of Attenuator Control StageOutput
OVERALL CONTROL CHARACTERISTICS OF ATTENUATOR
−52.3dB
0dB
0.2V 3VControl Signal
C3
V3
C4
V4
C5
V5
C6
V6
C7
V7
C8
V8
C9
V9
C10
V10
A1 A2 A3 A4 A5 A6 A7 A8 A9 A10
Figure 4. Piecewise Approximation to Logarithmic Control Characteristics.
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PGA POST-AMPLIFIERFigure 5 shows a simplified circuit diagram of the PGAblock. As stated before, the input to the PGA is ac coupledwith an internal capacitor. Provisions are made so that anexternal capacitor can be placed in parallel with the inter-nal capacitor, thus lowering the usable low-frequencybandwidth. The low-frequency bandwidth is set by the fol-lowing equation:
1(2 500k (220pF CEXTERNAL))
where CEXTERNAL is the external capacitor value in farads.
Care should be taken to avoid using too large a value ofcapacitor, as this can increase the power-on delay time.
The PGA gain is programmed with the same MGS bits thatcontrol the VCA maximum attenuation factor. For VCA-CNTL = 3V (no attenuation), the VCA + PGA gain will becontrolled by the programmed PGA gain (29dB to 43dB inapproximately 3dB steps). For clarity, the gain and attenu-ation factors are detailed in Table I.
Table 1. MGS Settings.
MGSSETTING
ATTENUATOR GAINVCACNTL = 0.2V TO 3V
ATTENUATOR +DIFFERENTIAL PGA
GAIN
000 Not Valid Not Valid
001 Not Valid Not Valid
010 −41.0dB to 0dB −12dB to 29dB
011 −43.3dB to 0dB −11.5dB to 31.8dB
100 −46.4dB to 0dB −11.5dB to 34.9dB
101 −48.2dB to 0dB −10.6dB to 37.6dB
110 −50.2dB to 0dB −9.8dB to 40.4dB
111 −52.3dB to 0dB −9.3dB to 43.3dB
The PGA architecture converts the single−ended signalfrom the VCA into a differential signal. Low input noise wasalso a requirement of the PGA design due to the largeamount of signal attenuation that can be asserted beforethe PGA. At minimum VCA attenuation (used for small in-put signals), the input buffer noise dominates; at maximumVCA attenuation (large input signals), the PGA noise dom-inates. Note that if the PGA output is single−ended, the ap-parent gain will be 6dB lower.
RS1
RL
RS2
VCAOUTP
+In
Q11
Q3
Q4
Q5
Q1
VCM
Q2
VCAOUTN
Q9
Q8
Q13
Q14
Q7
Q6
Q12
VDD
VCM
RL
Q10
−In
To BiasCircuitry
To BiasCircuitry
Figure 5. Simplified Block Diagram of PGA.
(1)
"#$%&
SBOS276A − AUGUST 2003 − REVISED AUGUST 2003
www.ti.com
13
LAYOUT CONSIDERATIONSThe VCA2619 is an analog amplifier capable of high gain.When working on a PCB layout for the VCA2619, it is rec-ommended to utilize a solid ground plane that is connectedto analog ground. This helps to maximize the noise perfor-mance of the VCA2619.
Adequate power−supply decoupling must be used in orderto achieve the best possible performance. Decoupling ca-pacitors on the VCACNTL voltage should also be used tohelp minimize noise. Recommended values can be ob-tained from the layout diagram of Figure 6.
0.1µF
0.1µF
+5V
1µF
0.1µF
1µF
1µF
0.01µF
0.01µF
0.01µF
0.01µF
0.01µF
0.01µF
+5V
0.1µF
1µF
1µF
0.1µF
0.1µF
VCACNTL
INB INB +OUTB +OUTB
−OUTB−OUTB
−OUTA
+5V
+OUTA+OUTA
−OUTAINAINA1
8
25
28
26
16
15
24413
3 5VDDA
VDDB VBIAS VCNTL
VDDR VCM
VCA2619
Figure 6. VCA2619 Layout.
PACKAGE OPTION ADDENDUM
www.ti.com 28-Aug-2010
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status (1) Package Type PackageDrawing
Pins Package Qty Eco Plan (2) Lead/Ball Finish
MSL Peak Temp (3) Samples
(Requires Login)
VCA2619YRG4 ACTIVE TQFP PBS 32 TBD Call TI Call TI Purchase Samples
VCA2619YT ACTIVE TQFP PBS 32 250 Green (RoHS& no Sb/Br)
CU NIPDAU Level-3-260C-168 HR Request Free Samples
(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 availabilityinformation 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 thatlead 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 betweenthe 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 weightin homogeneous material)
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
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 informationprovided 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 andcontinues 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.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device PackageType
PackageDrawing
Pins SPQ ReelDiameter
(mm)
ReelWidth
W1 (mm)
A0(mm)
B0(mm)
K0(mm)
P1(mm)
W(mm)
Pin1Quadrant
VCA2619YT TQFP PBS 32 250 177.8 16.4 7.2 7.2 1.5 12.0 16.0 Q2
PACKAGE MATERIALS INFORMATION
www.ti.com 17-Dec-2011
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
VCA2619YT TQFP PBS 32 250 210.0 185.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 17-Dec-2011
Pack Materials-Page 2
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