IC OPAMP VGA DIFF 80MHZ 48TQFP

VCA2612Y/250G4

Manufacturer Part NumberVCA2612Y/250G4
DescriptionIC OPAMP VGA DIFF 80MHZ 48TQFP
ManufacturerTexas Instruments
VCA2612Y/250G4 datasheet
 


Specifications of VCA2612Y/250G4

Amplifier TypeVariable GainNumber Of Circuits2
Output TypeDifferentialSlew Rate300 V/µs
Gain Bandwidth Product80MHz-3db Bandwidth40MHz
Current - Input Bias1nACurrent - Output / Channel40mA
Voltage - Supply, Single/dual (±)4.75 V ~ 5.25 VOperating Temperature-40°C ~ 85°C
Mounting TypeSurface MountPackage / Case48-TQFP, 48-VQFP
For Use WithVCA2611EVM - VCA2611EVMLead Free Status / RoHS StatusLead free / RoHS Compliant
Current - Supply-Voltage - Input Offset-
1
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Dual, VARIABLE GAIN AMPLIFIER
with Low Noise Preamp
FEATURES
LOW NOISE PREAMP:
• Low Input Noise: 1.25nV/ Hz
• Active Termination Noise Reduction
• Switchable Termination Value
• 80MHz Bandwidth
• 5dB to 25dB Gain Range
• Differential Input /Output
LOW NOISE VARIABLE GAIN AMPLIFIER:
• Low Noise VCA: 3.3nV/ Hz, Differential
Programming Optimizes Noise Figure
• 24dB to 45dB Gain
• 40MHz Bandwidth
• Differential Input /Output
LOW CROSSTALK: 52dB at Max Gain, 5MHz
HIGH-SPEED VARIABLE GAIN ADJUST
SWITCHABLE EXTERNAL PROCESSING
APPLICATIONS
ULTRASOUND SYSTEMS
WIRELESS RECEIVERS
TEST EQUIPMENT
RF
SWFB
2
RF
1
C
F
C
Input
C
LNP
P
IN
LNP
GS1
LNP
LNP
GS2
Gain Set
LNP
GS3
LNP
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.
All 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 Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
DESCRIPTION
The VCA2612 is a highly integrated, dual receive channel,
signal processing subsystem. Each channel of the product
consists of a low noise preamplifier (LNP) and a Variable
Gain Amplifier (VGA). The LNP circuit provides the neces-
sary connections to implement Active Termination (AT), a
method of cable termination which results in up to 4.6dB
noise figure improvement. Different cable termination char-
acteristics can be accommodated by utilizing the VCA2612’s
switchable LNA feedback pins. The LNP has the ability to
accept both differential and single-ended inputs, and gener-
ates a differential output signal. The LNP provides strappable
gains of 5dB, 17dB, 22dB, and 25dB.
The output of the LNP can be accessed externally for further
signal processing, or fed directly into the VGA. The VCA2612’s
VGA section consists of two parts: the Voltage Controlled
Attenuator (VCA) and the Programmable Gain Amplifier
(PGA). The gain and gain range of the PGA can be digitally
programmed. The combination of these two programmable
elements results in a variable gain ranging from 0dB up to a
maximum gain as defined by the user through external
connections. The output of the VGA can be used in either a
single-ended or differential mode to drive high-performance
Analog-to-Digital (A/D) converters.
The VCA2612 also features low crosstalk and outstanding
distortion performance. The combination of low noise and gain
range programmability make the VCA2612 a versatile building
block in a number of applications where noise performance is
critical. The VCA2612 is available in a TQFP-48 package.
FBSW
LNP
N
VCA
N
VCA
CNTL
OUT
IN
VCA2612
FB
(1 of 2 Channels)
Analog
Control
Voltage
Low Noise
Controlled
Preamp
Attenuator
5dB to 25dB
N
IN
SEL
LNP
P
VCA
P
OUT
IN
www.ti.com
VCA2612
SBOS117C – SEPTEMBER 2000 – REVISED APRIL 2004
Maximum Gain Select
CNTL
MGS
MGS
MGS
1
2
3
Maximum Gain
Select
VCA
N
OUT
Programmable
Gain Amplifier
24 to 45dB
VCA
P
OUT
Copyright © 2000-2004, Texas Instruments Incorporated

VCA2612Y/250G4 Summary of contents

  • Page 1

    ... LNP 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. All trademarks are the property of their respective owners. PRODUCTION DATA information is current as of publication date. ...

  • Page 2

    ABSOLUTE MAXIMUM RATINGS Power Supply (+V ) ............................................................................. +6V S Analog Input ............................................................. –0.3V to (+V Logic Input ............................................................... –0.3V to (+V Case Temperature ......................................................................... +100 C Junction Temperature .................................................................... +150 C Storage Temperature ...................................................... – +150 C ...

  • Page 3

    PIN CONFIGURATION VCA NA IN VCA PA IN LNP NA OUT LNP PA OUT SWFBA FBA COMP1A COMP2A LNP NA IN PIN DESCRIPTIONS PIN DESIGNATOR DESCRIPTION Channel A +Supply (+5V ...

  • Page 4

    TYPICAL CHARACTERISTICS + +5V, load resistance = 500 A DDA DDB DDR The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended unless otherwise ...

  • Page 5

    TYPICAL CHARACTERISTICS + +5V, load resistance = 500 A DDA DDB DDR The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended unless otherwise ...

  • Page 6

    TYPICAL CHARACTERISTICS + +5V, load resistance = 500 A DDA DDB DDR The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended unless otherwise ...

  • Page 7

    TYPICAL CHARACTERISTICS + +5V, load resistance = 500 A DDA DDB DDR The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended unless otherwise ...

  • Page 8

    TYPICAL CHARACTERISTICS + +5V, load resistance = 500 A DDA DDB DDR The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended unless otherwise ...

  • Page 9

    TYPICAL CHARACTERISTICS + +5V, load resistance = 500 A DDA DDB DDR The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended unless otherwise ...

  • Page 10

    TYPICAL CHARACTERISTICS + +5V, load resistance = 500 A DDA DDB DDR The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended unless otherwise ...

  • Page 11

    THEORY OF OPERATION The VCA2612 is a dual-channel system consisting of three primary blocks: a Low Noise Preamplifier (LNP), a Voltage Controlled Attenuator (VCA), and a Programmable Gain Amplifier (PGA). For greater system flexibility, an onboard multiplexer is provided for ...

  • Page 12

    PGA OVERVIEW AND OVERALL DEVICE CHARACTERISTICS The differential output of the VCA attenuator is then amplified by the PGA circuit block. This post-amplifier is programmed by the same MGS bits that control the VCA attenuator, yielding an overall swept-gain amplifier ...

  • Page 13

    R is the load resistor in the drains the resistor connected between the sources of the input S transistors Q and Q . The connections for various binations are brought out ...

  • Page 14

    R S LNP Conventional Cable Termination FIGURE 5. Configurations for Active Feedback and Conven- tional Cable Termination. of two (6dB) before being ...

  • Page 15

    Achieving the best active feedback architecture is difficult with conventional op amp circuit structures. The overall gain A must be negative in order to close the feedback loop, the input impedance must be high to maintain low current noise and ...

  • Page 16

    Attenuator Input Control Input 0dB –4.5dB 0dB –4.5dB 0.3V FIGURE 11. Piecewise Approximation ...

  • Page 17

    R S INPUT VCM FIGURE 12. Programmable Attenuator Section. Input impedance of the VCA will vary with gain setting, due to the changing resistances of the programmable voltage divider structure. At large ...

  • Page 18

    INPUT OVERLOAD RECOVERY One of the most important applications for the VCA2612 is processing signals in an ultrasound system. The ultrasound signal flow begins when a large signal is applied to a transducer, which converts electrical energy to acoustic energy. ...

  • Page 19

    ... PACKAGING INFORMATION Orderable Device (1) Package Type Package Status VCA2612Y/250 ACTIVE TQFP VCA2612Y/250G4 ACTIVE TQFP VCA2612Y/2K ACTIVE TQFP VCA2612Y/2KG4 ACTIVE TQFP (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. ...

  • Page 20

    PFB (S-PQFP-G48) 0, 5,50 TYP 7,20 SQ 6,80 9,20 SQ 8,80 1,05 0,95 1,20 MAX NOTES: A. All linear dimensions are in millimeters. B. This drawing is subject to change without notice. C. Falls within JEDEC ...

  • Page 21

    ...

  • Page 22

    ... 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 should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI’ ...