VCA2611

VCA2611 BURR-BROWN | Alldatasheet

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G LOW-NOISE PREAMP: – Low Input Noise: 0.95nV/√Hz – Active Termination Noise Reduction – Switchable Termination Value – 80MHz Bandwidth – 5dB to 25dB Gain – Differential In and Out G LOW-NOISE VARIABLE GAIN AMPLIFIER: – Low-Noise VCA – Up to 40dB Gain Range – 40MHz Bandwidth – Differential In and Out G LOW CROSSTALK: 66dB at Max Gain, 5MHz G HIGH-SPEED VARIABLE GAIN ADJUST G SWITCHABLE EXTERNAL PROCESSING APPLICA TIONS G ULTRASOUND SYSTEMS G WIRELESS RECEIVERS G TEST EQUIPMENT

DESCRIPTION

The VCA2616 and VCA2611 are dual, Low-Noise Preamplifiers (LNP), plus low-noise Variable Gain Amplifiers (VGA). The VCA2611 is an upgraded version of the VCA2616. The only difference between the VCA2616 and the VCA2611 is the input structure to the LNP. The VCA2616 is limited to –0.3V negative- going input spikes; the VCA2611 is limited to –2.0V negative- going input spikes. This change allows the user to use slower and less expensive input clamping diodes prior to the LNP input. In some designs, input clamping may not be required. The combination of Active Termination (AT) and Maximum Gain Select (MGS) allow for the best noise performance. The VCA2616 and VCA2611 also feature low crosstalk and out- standing distortion performance. The LNP has differential input and output capability and is strappable for gains of 5dB, 17dB, 22dB, or 25dB. Low input impedance is achieved by AT, resulting in as much as a 4.6dB improvement in noise figure over conventional shunt termina- tion. The termination value can also be switched to accommo- date different sources. The output of the LNP is available for external signal processing. The variable gain is controlled by an analog voltage whose gain varies from 0dB to the gain set by the MGS. The ability to program the variable gain also allows the user to optimize dynamic range. The VCA input can be switched from the LNP to external circuits for different applications. The output can be used in either a single-ended or differential mode to drive high- performance Analog-to-Digital (A/D) converters, and is cleanly limited for optimum overdrive recovery. The combination of low noise, gain, and gain range program- mability makes the VCA2616 and VCA2611 versatile building blocks in a number of applications where noise performance is critical. The VCA2616 and VCA2611 are available in a TQFP-48 package. Dual, Variable-Gain Amplifier with Low-Noise Preamp Low Noise Preamp 5dB to 25dB Programmable Gain Amplifier 24 to 45dB Voltage Controlled Attenuator Analog Control Maximum Gain Select RF 2 RF 1 FB FBSW LNP INP LNP INN LNP GS1 LNP GS2 LNP GS3 LNP Gain Set Input LNP OUT P SELVCA INP LNP OUT N VCA INN VCA CNTLFB CNTL VCA OUT P VCA OUT N MGS 1 MGS 2 MGS 3 Maximum Gain Select VCA2616 (1 of 2 Channels) VCA2616 VCA2611 SBOS234E – MARCH 2002 – REVISED NOVEMBER 2004 VCA2616 www.ti.com Copyright © 2002-2004, Texas Instruments Incorporated All trademarks are the property of their respective owners. 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. 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.

VCA2616, VCA26112 SBOS234Ewww.ti.com ABSOLUTE MAXIMUM RATINGS (1) SPECIFIED PACKAGE TEMPERATURE PACKAGE ORDERING TRANSPORT PRODUCT PACKAGE-LEAD DESIGNATOR RANGE MARKING NUMBER MEDIA, QUANTITY VCA2616 TQFP-48 PFB –40°C to +85°C VCA2616 VCA2616YT Tape and Reel, 250 "" " " " VCA2616YR Tape and Reel, 2000 VCA2611 TQFP-48 PFB –40°C to +85°C VCA2611 VCA2611Y/250 Tape and Reel, 250 "" " " " VCA2611Y/2K Tape and Reel, 2000 NOTE: (1) For the most current package and ordering information, see the Package Option Addendum located at the end of this data sheet. PACKAGE/ORDERING INFORMATION (1)

ELECTRICAL CHARACTERISTICS

At TA = +25°C, VDDA = VDDB = VDDR = +5V, load resistance = 500Ω on each output to ground, MGS = 011, LNP = 22dB and fIN = 5MHz, unless otherwise noted. The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended, unless otherwise noted. ELECTROSTATIC DISCHARGE SENSITIVITY This integrated circuit can be damaged by ESD. Texas Instru- ments 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 degrada- tion 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. NOTE: (1) Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. Exposure to absolute maximum conditions for extended periods may affect device reliability. NOTES: (1) For preamp driving VGA. (2) Referenced to best fit dB-linear curve. VCA2616Y, VCA2611Y PARAMETER CONDITIONS MIN TYP MAX UNITS PREAMPLIFIER Input Resistance 600 k Ω Input Capacitance 15 pF Input Bias Current 1n A CMRR f = 1MHz, VCA CNTL = 0.2V 50 dB Maximum Input Voltage Preamp Gain = +5dB 1 V PP Preamp Gain = +25dB 112 mV PP Input Voltage Noise(1) Preamp Gain = +5dB 4.2 nV/ √Hz Preamp Gain = +25dB 0.95 nV/ √Hz Input Current Noise Independent of Gain 0.35 pA/ √Hz Noise Figure, RS = 75Ω , RIN = 75Ω (1) R F = 550Ω , Preamp Gain = 22dB, 6.2 dB PGA Gain = 39dB Bandwidth Gain = 22dB 80 MHz PROGRAMMABLE VARIABLE GAIN AMPLIFIER Peak Input Voltage Differential 2 V PP –3dB Bandwidth 40 MHz Slew Rate 300 V/ µs Output Signal Range R L ≥ 500Ω Each Side to Ground 2 V PP Output Impedance f = 5MHz 1 Ω Output Short-Circuit Current ±40 mA 3rd-Harmonic Distortion f = 5MHz, V OUT = 1VPP , VCACNTL = 3.0V –45 –71 dBc 2nd-Harmonic Distortion f = 5MHz, V OUT = 1VPP , VCACNTL = 3.0V –45 –63 dBc IMD, 2-Tone V OUT = 2VPP , f = 1MHz –75 dBc VOUT = 2VPP , f = 10MHz –75 dBc Crosstalk VCA CNTL = 0.2V –66 dB Group Delay Variation 1MHz < f < 10MHz, Full Gain Range ±2n s DC Output Level, VIN = 0 2.5 V ACCURACY Gain Slope 10.9 dB/V Gain Error ±1(2) dB Output Offset Voltage ±50 mV Total Gain VCA CNTL = 0.2V 18 21 24 dB VCA CNTL = 3.0V 47 50 53 dB GAIN CONTROL INTERFACE Input Voltage (VCACNTL ) Range 0.2 to 3.0 V Input Resistance 1M Ω Response Time 40dB Gain Change, MGS = 111 0.2 µs POWER SUPPLY Operating Temperature Range –40 +85 °C Specified Operating Range 4.75 5.0 5.25 V Power Dissipation Operating, Both Channels 410 495 mW

VCA2616, VCA2611 3 SBOS234E www.ti.com PIN CONFIGURATION VDD B NC NC VCA INNB VCA INPB LNP OUT NB LNP OUT PB SWFBB FBB COMP1B COMP2B LNP INNB GNDA VCA OUT NA VCA OUT PA FBSW CNTL VCA INSEL VCA CNTL MGS 1 MGS 2 MGS 3 VCA OUT PB VCA OUT NB GNDB LNP GS3 A LNP GS2 A LNP GS1 A LNP INPA VDD R VBIAS VCM GNDR LNP INPB LNP GS1 B LNP GS2 B LNP GS3 B VDD A NC NC VCA INNA VCA INPA LNP OUT NA LNP OUT PA SWFBA FBA COMP1A COMP2A LNP INNA 48 47 46 45 44 43 42 41 40 39 38 13 14 15 16 17 18 19 20 21 22 23 VCA2616 VCA2611 1V DD A Channel A +Supply

2 NC Do Not Connect

3 NC Do Not Connect

4 VCA

INNA Channel A VCA Negative Input

5 VCA INPA Channel A VCA Positive Input

6L N P OUT NA Channel A LNP Negative Output 7L N P OUT PA Channel A LNP Positive Output

8 SWFBA Channel A Switched Feedback Output

9 FBA Channel A Feedback Output

10 COMP1A Channel A Frequency Compensation 1

11 COMP2A Channel A Frequency Compensation 2

12 LNP

INNA Channel A LNP Inverting Input

13 LNP GS3 A Channel A LNP Gain Strap 3

14 LNP GS2 A Channel A LNP Gain Strap 2

15 LNP GS1 A Channel A LNP Gain Strap 1

16 LNP INPA Channel A LNP Noninverting Input

17 V DD R +Supply for Internal Reference

18 V BIAS 0.01µF Bypass to Ground 19 V CM 0.01µF Bypass to Ground

20 GNDR Ground for Internal Reference

21 LNP

INPB Channel B LNP Noninverting Input

22 LNP GS1 B Channel B LNP Gain Strap 1

23 LNP GS2 B Channel B LNP Gain Strap 2

24 LNP GS3 B Channel B LNP Gain Strap 3

25 LNP INNB Channel B LNP Inverting Input

26 COMP2B Channel B Frequency Compensation 2

27 COMP1B Channel B Frequency Compensation 1

28 FBB Channel B Feedback Output

29 SWFBB Channel B Switched Feedback Output

30 LNP

OUT PB Channel B LNP Positive Output

31 LNP OUT NB Channel B LNP Negative Output

32 VCA INPB Channel B VCA Positive Input

33 VCA INNB Channel B VCA Negative Input

34 NC Do Not Connect

35 NC Do Not Connect

DD B Channel B +Analog Supply

37 GNDB Channel B Analog Ground

38 VCA

OUT NB Channel B VCA Negative Output

39 VCA OUT PB Channel B VCA Positive Output

40 MGS 3 Maximum Gain Select 3 (LSB)

41 MGS 2 Maximum Gain Select 2

42 MGS 1 Maximum Gain Select 1 (MSB)

43 VCA CNTL VCA Control Voltage

44 VCA INSEL VCA Input Select, HI = External

45 FBSW CNTL Feedback Switch Control: HI = ON

46 VCA OUT PA Channel A VCA Positive Output

47 VCA OUT NA Channel A VCA Negative Output

48 GNDA Channel A Analog Ground

PIN DESIGNATOR DESCRIPTION PIN DESIGNATOR DESCRIPTION PIN DESCRIPTIONS Top View TQFP

VCA2616, VCA26114 SBOS234Ewww.ti.com TYPICAL CHARACTERISTICS At TA = +25°C, VDDA = VDDB = VDDR = +5V, load resistance = 500Ω on each output to ground, MGS = 011, LNP = 22dB and fIN = 5MHz, unless otherwise noted. The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended, unless otherwise noted. This results in a 6dB reduction in signal amplitude compared to differential operation. GAIN vs VCACNTL VCA CNTL (V) Gain (dB) MGS = 110 MGS = 111 MGS = 101 MGS = 100 MGS = 011MGS = 010 MGS = 001MGS = 000 GAIN ERROR vs TEMPERATURE VCA CNTL (V) Gain Error (dB) 2.0 1.5 1.0 0.5 0.0 –0.5 –1.0 –1.5 –2.0 +85°C –40°C +25°C GAIN ERROR vs VCA CNTL VCA CNTL (V) Gain Error (dB) 2.0 1.5 1.0 0.5 0.0 –0.5 –1.0 –1.5 –2.0 10MHz 1MHz 5MHz GAIN ERROR vs VCA CNTL VCA CNTL (V) Gain Error (dB) 2.0 1.5 1.0 0.5 –0.5 –1.0 –1.5 –2.0 MGS = 011MGS = 000 MGS = 111 GAIN MATCH 0.2V CHA to CHB Delta Gain (dB) Units –0.55 –0.48 –0.42 –0.35 –0.29 –0.22 –0.16 –0.09 –0.03 0.04 0.16 0.10 0.23 0.36 0.29 Delta Gain (dB) –0.26 –0.23 –0.20 –0.17 –0.14 –0.10 0.07 0.04 0.01 0.02 0.09 0.05 0.12 0.18 0.15 Units GAIN MATCH 3.0V CHA to CHB

VCA2616, VCA2611 5 SBOS234E www.ti.com TYPICAL CHARACTERISTICS (Cont.) At TA = +25°C, VDDA = VDDB = VDDR = +5V, load resistance = 500Ω on each output to ground, MGS = 011, LNP = 22dB and fIN = 5MHz, unless otherwise noted. The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended, unless otherwise noted. This results in a 6dB reduction in signal amplitude compared to differential operation. GAIN vs FREQUENCY (Pre-Amp) Frequency (Hz) Gain (dB) LNA = 25dB LNA = 22dB LNA = 17dB LNA = 5dB 100k 1M 10M 100M GAIN vs FREQUENCY VCA (VCA CNTL = 0.2V) Frequency (Hz) Gain (dB) 5.0 4.0 3.0 2.0 1.0 0.0 –1.0 –2.0 –3.0 –4.0 –5.0 MGS = 111 MGS = 100 MGS = 011 MGS = 000 100k 1M 10M 100M GAIN vs FREQUENCY VCA (VCA CNTL = 3.0V) Frequency (Hz) Gain (dB) MGS = 111 MGS = 100 MGS = 011 MGS = 000 100k 1M 10M 100M GAIN vs FREQUENCY LNA and VCA (VCA CNTL = 3.0V) Frequency (Hz) 100k 1M 10M 100M Gain (dB) LNP = 25dB LNP = 22dB LNP = 5dB LNP = 17dB GAIN vs FREQUENCY LNA and VCA (LNP = 22dB) Frequency (Hz) Gain (dB) VCNTL = 3.0V VCNTL = 1.6V VCNTL = 0.2V 100k 1M 10M 100M OUTPUT-REFERRED NOISE vs VCA CNTL (LNP = 25dB) VCA CNTL (V) Noise (nV/√Hz) 2000 1800 1600 1400 1200 1000 800 600 400 200 R S= 50Ω MGS = 111 MGS = 011

VCA2616, VCA26116 SBOS234Ewww.ti.com TYPICAL CHARACTERISTICS (Cont.) At TA = +25°C, VDDA = VDDB = VDDR = +5V, load resistance = 500Ω on each output to ground, MGS = 011, LNP = 22dB and fIN = 5MHz, unless otherwise noted. The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended unless otherwise noted. This results in a 6dB reduction in signal amplitude compared to differential operation. INPUT-REFERRED NOISE vs VCA CNTL (LNP = 25dB) VCA CNTL (V) Noise (nV/√Hz) MGS = 011 MGS = 111 R S = 50Ω INPUT-REFERRED NOISE vs R S (LNP = 25dB) R S (Ω ) 1 10 100 1k Noise (nV√Hz) 10.0 1.0 0.1 MGS = 111 NOISE FIGURE vs RS (LNP = 25dB) R S (Ω ) 10 100 1k Noise Figure (dB) MGS = 111 Noise Figure (dB) VCA CNTL (V) NOISE FIGURE vs VCA CNTL (LNP = 25dB) MGS = 111 DISTORTION vs FREQUENCY MGS = 000 2VPP DIFFERENTIAL Frequency (Hz) 100k 1M 10M Harmonic (dBc) –30 –35 –40 –45 –50 –55 –60 –65 –70 –75 –80 –85 VC = 0.2, H2 VC = 0.2, H3 VC = 3.0, H2 VC = 3.0, H3 DISTORTION vs FREQUENCY MGS = 011 2VPP DIFFERENTIAL Frequency (Hz) 100k 1M 10M Distortion (dBc) –30 –35 –40 –45 –50 –55 –60 –65 –70 –75 –80 –85 –90 VC = 0.2, H2 VC = 3.0, H2 VC = 3.0, H3 VC = 0.2, H3

VCA2616, VCA2611 7 SBOS234E www.ti.com TYPICAL CHARACTERISTICS (Cont.) At TA = +25°C, VDDA = VDDB = VDDR = +5V, load resistance = 500Ω on each output to ground, MGS = 011, LNP = 22dB and fIN = 5MHz, unless otherwise noted. The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended, unless otherwise noted. This results in a 6dB reduction in signal amplitude compared to differential operation. DISTORTION vs FREQUENCY MGS = 111 2VPP DIFFERENTIAL Frequency (Hz) 100k 1M 10M Distortion (dBc) –30 –35 –40 –45 –50 –55 –60 –65 –70 –75 –80 VC = 0.2, H2 VC = 0.2, H3 VC = 3.0, H3 VC = 3.0, H2 DISTORTION vs FREQUENCY MGS = 000 1VPP SINGLE-ENDED Frequency (Hz) 100k 1M 10M Distortion (dBc) –30 –35 –40 –45 –50 –55 –60 –65 –70 –75 –80 –85 –90 VC = 0.2, H3 VC = 0.2, H2 VC = 3.0, H2 VC = 3.0, H3 DISTORTION vs FREQUENCY MGS = 011 1VPP SINGLE-ENDED Frequency (Hz) 100k 1M 10M Distortion (dBc) –30 –35 –40 –45 –50 –55 –60 –65 –70 –75 –80 –85 –90 VC = 0.2, H3 VC = 0.2, H2 VC = 3.0, H2 VC = 3.0, H3 DISTORTION vs FREQUENCY MGS = 111 1VPP SINGLE-ENDED Frequency (Hz) 100k 1M 10M Distortion (dBc) –30 –35 –40 –45 –50 –55 –60 –65 –70 –75 –80 –85 –90 VC = 0.2, H2 VC = 0.2, H3 VC = 3.0, H2 VC = 3.0, H3 DISTORTION vs VCA CNTL 2VPP DIFFERENTIAL VCA CNTL (V) Distortion (dBc) –45 –50 –55 –60 –65 –70 –75 –80 MGS = 011, H2 MGS = 000, H2 MGS = 111, H3 MGS = 011, H3 MGS = 000, H3 MGS = 111, H2 DISTORTION vs VCA CNTL 1VPP SINGLE-ENDED VCA CNTL (V) Distortion (dBc) –45 –50 –55 –60 –65 –70 –75 –80 MGS = 011, H2 MGS = 000, H2 MGS = 000, H3 MGS = 111, H3 MGS = 011, H3 MGS = 111, H2

VCA2616, VCA26118 SBOS234Ewww.ti.com TYPICAL CHARACTERISTICS (Cont.) At TA = +25°C, VDDA = VDDB = VDDR = +5V, load resistance = 500Ω on each output to ground, MGS = 011, LNP = 22dB and fIN = 5MHz, unless otherwise noted. The input to the preamp (LNP) is single-ended, and the output from the VCA is single-ended, unless otherwise noted. This results in a 6dB reduction in signal amplitude compared to differential operation. –15 –25 –35 –45 –55 –65 –75 –85 Crosstalk (dB) CROSSTALK vs FREQUENCY 1VPP SINGLE-ENDED MGS = 011 Frequency (Hz) 1M 10M 100M VCA CNTRL 0V VCA CNTRL 1.5V VCA CNTRL 3.0V ICC vs TEMPERATURE Temperature (°C) –20–30–40 –1 00 1 02 03 04 05 06 07 08 09 0 ICC (dBFS) 80.50 80.00 79.50 79.00 78.50 78.00 77.50 77.00 76.50 76.00 Group Delay (nS) 1M 10M 100M Frequency (Hz) GROUP DELAY vs FREQUENCY VC = 3.0 VC = 0.2

each circuit block are provided in the following sections. signal at the gate-source input of Q4, the +IN side of the LNP. through Q10 play the same role for signals on the –IN side. FIGURE 4. Schematic of the Low-Noise Preamplifier (LNP). 59µs at the lowest gain (25dB).

VCA2616, VCA2611 11 SBOS234E www.ti.com LNP GAIN (dB) Input-Referred Output-Referred 25 1.35 2260 22 1.41 1650 17 1.63 1060 5 4.28 597 The LNP is capable of generating a 2VPP differential signal. The maximum signal at the LNP input is therefore 2VPP divided by the LNP gain. An input signal greater than this would exceed the linear range of the LNP, an especially important consideration at low LNP gain settings. The VCA2611 is an upgraded version of the VCA2616. The only difference between the VCA2616 and the VCA2611 is the input structure to the LNP. The VCA2616 is limited to –0.3V negative-going input spikes; the VCA2611 is limited to –2.0V negative-going input spikes. This change allows the user to use slower and less expensive input clamping diodes prior to the LNA input. In some designs, input clamping may not be required. ACTIVE FEEDBACK WITH THE LNP One of the key features of the LNP architecture is the ability to employ active-feedback termination to achieve superior noise performance. Active-feedback termination achieves a lower noise figure than conventional shunt termination, es- sentially because no signal current is wasted in the termina- tion resistor itself. Another way to understand this is to consider first that the input source, at the far end of the signal cable, has a cable-matching source resistance of R S. Using conventional shunt termination at the LNP input, a second terminating resistor of value R S is connected to ground. Therefore, the signal loss is 6dB due to the voltage divider action of the series and shunt R S resistors. The effective source resistance has been reduced by the same factor of 2, but the noise contribution has been reduced by only the √2, only a 3dB reduction. Therefore, the net theoretical SNR degradation is 3dB, assuming a noise-free amplifier input. (In practice, the amplifier noise contribution will degrade both the unterminated and the terminated noise figures, some- what reducing the distinction between them.) See Figure 5 for an amplifier using active feedback. This diagram appears very similar to a traditional inverting ampli- fier. However, the analysis is somewhat different because the gain A in this case is not a very large open-loop op amp gain; rather, it is the relatively low and controlled gain of the LNP itself. Thus, the impedance at the inverting amplifier terminal will be reduced by a finite amount, as given in the familiar relationship of Equation 3: R R A IN F= +( )1 (3) where RF is the feedback resistor (supplied externally be- tween the LNPINP and FB terminals for each channel), A is It is also possible to create other gain settings by connecting an external resistor between LNPGS1 on one side, and LNPG S2 and/or LNPGS3 on the other. In that case, the internal resistor values (see Figure 4) should be combined with the external resistor to calculate the effective value of R S for use in Equation 1. The resulting expression for external resistor value is given in Equation 2: R R R R R Gain R R Gain R REXT S L FIX L S FIX S L = +× where REXT is the externally selected resistor value needed to achieve the desired gain setting, RS1 is the fixed parallel resistor in Figure 4, and RFIX is the effective fixed value of the remaining internal resistors: RS2, RS3, or (RS2 || RS3), de- pending on the pin connections. Note that the best process and temperature stability will be achieved by using the pre-programmed fixed-gain options of Table I, since the gain is then set entirely by internal resistor ratios, which are typically accurate to ±0.5%, and track quite well over process and temperature. When combining exter- nal resistors with the internal values to create an effective R S value, note that the internal resistors have a typical tempera- ture coefficient of +700ppm/°C and an absolute value toler- ance of approximately ±5%, yielding somewhat less predict- able and stable gain settings. With or without external resis- tors, the board layout should use short Gain Strap connec- tions to minimize parasitic resistance and inductance effects. The overall noise performance of the VCA2616 and VCA2611 will vary as a function of gain. Table II shows the typical input- and-output-referred noise densities of the entire VCA2616 and VCA2611 for maximum VCA and PGA gain; that is, VCA CNTL set to 3.0V and all MGS bits set to 1. Note that the input- referred noise values include the contribution of a 50Ω fixed source impedance, and are therefore somewhat larger than the intrinsic input noise. As the LNP gain is reduced, the noise contribution from the VCA/PGA portion becomes more signifi- cant, resulting in higher input-referred noise. However, the output-referred noise, which is indicative of the overall SNR at that gain setting, is reduced. To preserve the low-noise performance of the LNP, the user should take care to minimize resistance in the input lead. A parasitic resistance of only 10Ω will contribute 0.4nV/ √Hz . NOISE (nV/√ Hz) TABLE II. Equivalent Noise Performance for MGS = 111 and VCA CNTL = 3.0V with 50Ω source impedance. LNP PIN STRAPPING LNP GAIN (dB) LNPG S1, LNPGS2, LNPGS3 Connected Together 25 LNPG S1 Connected to LNPGS3 22 LNPG S1 Connected to LNPGS2 17 All Pins Open 5 TABLE I. Pin Strappings of the LNP for Various Gains. (2) where RL is the load resistor in the drains of Q3 and Q8, and R S is the resistor connected between the sources of the input transistors Q4 and Q7. The connections for various RS com- binations are brought out to device pins LNPGS1, LNPGS2, and LNPG S3 (pins 13-15 for channel A, 22-24 for channel B). These Gain Strap pins allow the user to establish one of four fixed LNP gain options as shown in Table I.

FC C time constant be set to about 5µs. very low value resistors to maintain good voltage noise. tial signal handling at both input and output. effective R of the RC time constant is approximately 186Ω . various impedances that are connected to the LNP.

2 C(R )(R )

mance in all respects, except in the area of noise performance. tance that is a function of the devices shown in Figure 4. FIGURE 9. Open-Loop Gain Characteristic of LNP . FIGURE 10. LNP with Compensation Capacitor. FIGURE 11. VCA2616 and VCA2611 Input Impedance.

FIGURE 12. Piecewise Approximation to Logarithmic Control Characteristics.

Orderable Device Status(1) Package Type Package Drawing Pins Package Qty Eco Plan(2) Lead/Ball FinishMSL Peak Temp (3) VCA2611Y/250 ACTIVE TQFP PFB 48 250 TBD CU SNPB Level-2-220C-1 YEAR VCA2611Y/2K ACTIVE TQFP PFB 48 2000 TBD CU SNPB Level-2-220C-1 YEAR VCA2616YR ACTIVE TQFP PFB 48 2000 TBD CU SNPB Level-3-235C-168 HR VCA2616YT ACTIVE TQFP PFB 48 250 TBD CU SNPB Level-3-235C-168 HR (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) or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontentfor 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. 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. 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. PACKAGE OPTION ADDENDUM www.ti.com 18-Mar-2005 Addendum-Page 1

MTQF019A – JANUARY 1995 – REVISED JANUARY 1998 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 PFB (S-PQFP-G48) PLASTIC QUAD FLATPACK 4073176/B 10/96 Gage Plane 0,13 NOM 0,25 0,45 0,75 Seating Plane 0,05 MIN 0,17 0,27 SQ 7,20 6,80 5,50 TYP SQ8,80 9,20 1,05 0,95 1,20 MAX 0,08 0,50 M0,08 0°–7° NOTES: A. All linear dimensions are in millimeters. B. This drawing is subject to change without notice. C. Falls within JEDEC MS-026

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