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

www.ti.com

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.

! !

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

2

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.

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

3

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.

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

4

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

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

5

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

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

6

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)

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

7

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

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

8

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

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

9

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.

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

10

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.

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

11

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.

"#$%&

SBOS276A − AUGUST 2003 − REVISED AUGUST 2003

www.ti.com

12

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

IMPORTANT NOTICE

Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements,and other changes to its products and services at any time and to discontinue any product or service without notice. Customers shouldobtain the latest relevant information before placing orders and should verify that such information is current and complete. All products aresold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.

TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standardwarranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except wheremandated by government requirements, testing of all parameters of each product is not necessarily performed.

TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products andapplications using TI components. To minimize the risks associated with customer products and applications, customers should provideadequate design and operating safeguards.

TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right,or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Informationpublished by TI regarding third-party products or services does not constitute a license from TI to use such products or services or awarranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectualproperty of the third party, or a license from TI under the patents or other intellectual property of TI.

Reproduction of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompaniedby all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptivebusiness practice. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additionalrestrictions.

Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids allexpress and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is notresponsible or liable for any such statements.

TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would reasonablybe expected to cause severe personal injury or death, unless officers of the parties have executed an agreement specifically governingsuch use. Buyers represent that they have all necessary expertise in the safety and regulatory ramifications of their applications, andacknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their productsand any use of TI products in such safety-critical applications, notwithstanding any applications-related information or support that may beprovided by TI. Further, Buyers must fully indemnify TI and its representatives against any damages arising out of the use of TI products insuch safety-critical applications.

TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products arespecifically designated by TI as military-grade or "enhanced plastic." Only products designated by TI as military-grade meet militaryspecifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is solely atthe Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in connection with such use.

TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products aredesignated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any non-designatedproducts in automotive applications, TI will not be responsible for any failure to meet such requirements.

Following are URLs where you can obtain information on other Texas Instruments products and application solutions:

Products Applications

Audio www.ti.com/audio Communications and Telecom www.ti.com/communications

Amplifiers amplifier.ti.com Computers and Peripherals www.ti.com/computers

Data Converters dataconverter.ti.com Consumer Electronics www.ti.com/consumer-apps

DLP® Products www.dlp.com Energy and Lighting www.ti.com/energy

DSP dsp.ti.com Industrial www.ti.com/industrial

Clocks and Timers www.ti.com/clocks Medical www.ti.com/medical

Interface interface.ti.com Security www.ti.com/security

Logic logic.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense

Power Mgmt power.ti.com Transportation and Automotive www.ti.com/automotive

Microcontrollers microcontroller.ti.com Video and Imaging www.ti.com/video

RFID www.ti-rfid.com

OMAP Mobile Processors www.ti.com/omap

Wireless Connectivity www.ti.com/wirelessconnectivity

TI E2E Community Home Page e2e.ti.com

Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265Copyright © 2011, Texas Instruments Incorporated