Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Op-amp Variable gain VSSOP 10

VCA820

G+

G-

-V

20W

IN+

IN-

VCA820

Frequency(Hz)

Common-ModeRejectionRatio(dB)

100k 100M

10M1M

Input-Referred

VCA820

www.ti.com

............................................................................................................................................ SBOS395C –OCTOBER 2007–REVISED OCTOBER 2009

Wideband, > 40dB Adjust Range, Linear in dB

VARIABLE GAIN AMPLIFIER

Check for Samples: VCA820

FEATURES

DESCRIPTION

• 150MHz SMALL-SIGNAL BANDWIDTH

The VCA820 is a dc-coupled, wideband, linear in dB,

• 137MHz, 5V

BANDWIDTH (G = +10V/V)

continuously variable, voltage-controlled gain

• 0.1dB GAIN FLATNESS to 28MHz

amplifier. It provides a differential input to

• 1700V/μs SLEW RATE

single-ended conversion with a high-impedance gain

control input used to vary the gain down 40dB from

• > 40dB GAIN ADJUST RANGE

the nominal maximum gain set by the gain resistor

• HIGH GAIN ACCURACY: 20dB ±0.4dB

) and feedback resistor (R

• HIGH OUTPUT CURRENT: 160mA

The VCA820 internal architecture consists of two

input buffers and an output current feedback amplifier

APPLICATIONS

stage integrated with a multiplier core to provide a

• AGC RECEIVERS with RSSI

complete variable gain amplifier (VGA) system that

• DIFFERENTIAL LINE RECEIVERS

does not require external buffering. The maximum

gain is set externally with two resistors, providing

• PULSE AMPLITUDE COMPENSATION

flexibility in designs. The maximum gain is intended

• VARIABLE ATTENUATORS

to be set between +2V/V and +100V/V. Operating

• DROP-IN UPGRADE TO LMH6502

from ±5V supplies, the gain control voltage for the

VCA820 adjusts the gain linearly in dB as the control

voltage varies from 0V to +2V. For example, set for a

maximum gain of +10V/V, the VCA820 provides

20dB, at +2V input, to –20dB at 0V input of gain

control range. The VCA820 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 ±0.4dB

(maximum at +25°C).

Figure 1. Differential Equalizer

VCA820 RELATED PRODUCTS

GAIN

ADJUST INPUT SIGNAL

RANGE NOISE BANDWIDTH

SINGLES DUALS (dB) (nV/√Hz) (MHz)

VCA810 — 80 2.4 35

— VCA2612 45 1.25 80

— VCA2613 45 1 80

— VCA2615 52 0.8 50

— VCA2617 48 4.1 50

VCA820 — 40 8.2 150

VCA821 — 40 7.0 420

VCA822 — 40 8.2 150

VCA824 — 40 7.0 420

Figure 2. Common-Mode Rejection Ratio

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.

2X2Y is a trademark of X2Y Corporation.

3All 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.

Summary of content (37 pages)

PAGE 1
VCA820 VC A8 20 VC A820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 Wideband, > 40dB Adjust Range, Linear in dB VARIABLE GAIN AMPLIFIER Check for Samples: VCA820 FEATURES 1 • • • • • • • 23 150MHz SMALL-SIGNAL BANDWIDTH 137MHz, 5VPP BANDWIDTH (G = +10V/V) 0.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ 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.
PAGE 3
VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 ELECTRICAL CHARACTERISTICS: VS = ±5V At AVMAX = 20dB, RF = 1kΩ, RG = 200Ω, and RL = 100Ω, unless otherwise noted.
PAGE 4
VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com ELECTRICAL CHARACTERISTICS: VS = ±5V (continued) At AVMAX = 20dB, RF = 1kΩ, RG = 200Ω, and RL = 100Ω, unless otherwise noted.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 TYPICAL CHARACTERISTICS: VS = ±5V, DC Parameters At TA = +25°C, RL = 100Ω, VG = +1V, and VIN = single-ended input on +VIN with –VIN at ground, unless otherwise noted. MAXIMUM DIFFERENTIAL INPUT VOLTAGE vs GAIN RESISTOR 40 IRG MAX = 2.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V, DC and Power-Supply Parameters At TA = +25°C, RL = 100Ω, VG = +1V, and VIN = single-ended input on +VIN with –VIN at ground, unless otherwise noted.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 6dB At TA = +25°C, RL = 100Ω, RF = 1.33kΩ, RG = 1.33kΩ, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14 package, unless otherwise noted.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 6dB (continued) At TA = +25°C, RL = 100Ω, RF = 1.33kΩ, RG = 1.33kΩ, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14 package, unless otherwise noted.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 6dB (continued) At TA = +25°C, RL = 100Ω, RF = 1.33kΩ, RG = 1.33kΩ, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14 package, unless otherwise noted.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 6dB (continued) At TA = +25°C, RL = 100Ω, RF = 1.33kΩ, RG = 1.33kΩ, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14 package, unless otherwise noted.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 20dB At TA = +25°C, RL = 100Ω, RF = 1kΩ, RG = 200Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless otherwise noted.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 20dB (continued) At TA = +25°C, RL = 100Ω, RF = 1kΩ, RG = 200Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless otherwise noted.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 20dB (continued) At TA = +25°C, RL = 100Ω, RF = 1kΩ, RG = 200Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless otherwise noted.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 20dB (continued) At TA = +25°C, RL = 100Ω, RF = 1kΩ, RG = 200Ω, VG = +2V, and VIN = single-ended input on +VIN with –VIN at ground, unless otherwise noted. OUTPUT LIMITED OVERDRIVE RECOVERY AVMAX = 20dB VG = +1V Output Voltage Right Scale 4 0.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 40dB At TA = +25°C, RL = 100Ω, RF = 845Ω, RG = 16.9Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14 package, unless otherwise noted.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 40dB (continued) At TA = +25°C, RL = 100Ω, RF = 845Ω, RG = 16.9Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14 package, unless otherwise noted.
PAGE 17
VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 40dB (continued) At TA = +25°C, RL = 100Ω, RF = 845Ω, RG = 16.9Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14 package, unless otherwise noted.
PAGE 18
VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V, AVMAX = 40dB (continued) At TA = +25°C, RL = 100Ω, RF = 845Ω, RG = 16.9Ω, VG = +2V, VIN = single-ended input on +VIN with –VIN at ground, and SO-14 package, unless otherwise noted. GROUP DELAY vs FREQUENCY 4.0 12 3.5 1MHz 10 3.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 APPLICATION INFORMATION 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.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com DIFFERENCE AMPLIFIER DIFFERENTIAL EQUALIZER Because both inputs of the VCA820 are high-impedance, a difference amplifier can be implemented without any major problem. This implementation is shown in Figure 77.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 2.0 9 3 Gain (dB) 0 -3 -6 Initial Frequency Response of VCA820 with RC Load -9 -12 -15 -18 Cable Attenuations 1694F Cable Attenuation (dB) Equalizer Gain (dB) Equalized Frequency Response 6 1.5 1.0 VCA820 with Equalization 0.5 0 -0.5 -21 -1.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com AGC LOOP The demonstration fixtures can be requested at the Texas Instruments web site (www.ti.com) through the VCA820 product folder. In the typical AGC loop shown in Figure 83, the OPA695 follows the VCA820 to provide 40dB of overall gain.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 Table 2. SO-14 and MSOP-10 RF and RG Configurations OPERATING SUGGESTIONS 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.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com MAXIMUM GAIN OF OPERATION OUTPUT CURRENT AND VOLTAGE This section describes the use of the VCA820 in a fixed-gain application in which the VG control pin is set at VG = +2V. The tradeoffs described here are with bandwidth, gain, and output voltage range.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 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.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com NOISE RF The VCA820 offers 8.2nV/√Hz input-referred voltage noise density at a gain of 20dB and 1.8pA/√Hz input-referred current noise density.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 VG inINPUT VG +VIN V+ RS1 * * enINPUT 4kTRS1 FB x1 RF +RG * inINPUT VOUT RG (Noiseless) ICORE 4kTRF * eO iinOUTPUT VREF -RG x1 RF enOUTPUT * enINPUT iniOUTPUT * 4kTRF -VIN VRS2 inINPUT GND * 4kTRS2 Figure 89.
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VCA820 SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009............................................................................................................................................ www.ti.com BOARD LAYOUT Achieving optimum performance with a high-frequency amplifier such as the VCA820 requires careful attention to printed circuit board (PCB) layout parasitics and external component types.
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VCA820 www.ti.com............................................................................................................................................ SBOS395C – OCTOBER 2007 – REVISED OCTOBER 2009 REVISION HISTORY NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision B (December, 2008) to Revision C ..........................................................................................
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE OPTION ADDENDUM www.ti.com (4) 18-Oct-2013 There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (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.
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PACKAGE MATERIALS INFORMATION www.ti.com 19-Nov-2012 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing VCA820IDGSR VSSOP DGS 10 VCA820IDGST VSSOP DGS VCA820IDR SOIC D SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant 2500 330.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1 10 250 180.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1 14 2500 330.0 16.4 6.5 9.0 2.1 8.0 16.
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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) VCA820IDGSR VSSOP DGS 10 2500 367.0 367.0 35.0 VCA820IDGST VSSOP DGS 10 250 210.0 185.0 35.0 VCA820IDR SOIC D 14 2500 367.0 367.0 38.
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