LT6600-15 Very Low Noise, Differential Amplifi er and 15MHz Lowpass Filter FEATURES DESCRIPTION APPLICATIONS TYPICAL APPLICATION

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FEATURES n Programmable Differential Gain via Two External Resistors n Adjustable Output Common Mode oltage n Operates and Specifi ed with,, ± Supplies n.db Ripple th Order Lowpass Filter with MHz Cutoff n db S/N with Supply and P-P Output n Low Distortion, P-P, Ω Load, S = MHz: dbc nd, 9dBc rd MHz: dbc nd, 9dBc rd n Fully Differential Inputs and Outputs n Compatible with Popular Differential Amplifi er Pinouts n SO- Package APPLICATIONS n High Speed ADC Antialiasing and DAC Smoothing in Networking or Cellular Base Station Applications n High Speed Test and Measurement Equipment n Medical Imaging n Drop-In Replacement for Differential Amplifi ers L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. DESCRIPTION LT- ery Low Noise, Differential Amplifi er and MHz Lowpass Filter The LT - combines a fully differential amplifier with a th order MHz lowpass filter approximating a Chebyshev frequency response. Most differential amplifiers require many precision external components to tailor gain and bandwidth. In contrast, with the LT-, two external resistors program differential gain, and the filter s MHz cutoff frequency and passband ripple are internally set. The LT- also provides the necessary level shifting to set its output common mode voltage to accommodate the reference voltage requirements of A/Ds. Using a proprietary internal architecture, the LT- integrates an antialiasing filter and a differential amplifier/ driver without compromising distortion or low noise performance. At unity gain the measured in band signal-to-noise ratio is an impressive db. At higher gains the input referred noise decreases so the part can process smaller input differential signals without significantly degrading the output signal-to-noise ratio. The LT- also features low voltage operation. The differential design provides outstanding performance for a P-P signal level while the part operates with a single supply. The LT- is packaged in an SO- and is pin compatible with standalone differential amplifiers. TYPICAL APPLICATION IN.μF Ω Ω LT-.μF MID OCM GAIN = Ω/ Ω Ω.pF.pF.pF A IN CM LTC9.μF D OUT TAa AMPLITUDE (db) 9 An 9 Point FFT Spectrum INPUT.MHz P-P f SAMPLE = MHz TAb fb

LT- ABSOLUTE MAXIMUM RATINGS (Note ) Total Supply oltage... Input Current (Note )...±ma Operating Temperature Range (Note )... C to C Specifi ed Temperature Range (Note )... C to C Junction Temperature... C Storage Temperature Range... C to C Lead Temperature (Soldering, sec)... C PIN CONFIGURATION IN OCM OUT TOP IEW IN S PACKAGE -LEAD PLASTIC SO T JMAX = C, θ JA = C/W MID OUT ORDEFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTCS-#PBF LTCS-#TRPBF -Lead Plastic SO C to C LTIS-#PBF LTIS-#TRPBF I -Lead Plastic SO C to C LEAD BASED FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTCS- LTCS-#TR -Lead Plastic SO C to C LTIS- LTIS-#TR I -Lead Plastic SO C to C Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T A = C. Unless otherwise specified S = ( =, = ), = Ω, and R LOAD = k. PARAMETER CONDITIONS MIN TYP MAX UNITS Filter Gain, S = IN = P-P, f IN = DC to khz... db IN = P-P, f IN =.MHz (Gain Relative to khz) l.. db IN = P-P, f IN =.MHz (Gain Relative to khz) l.. db IN = P-P, f IN = MHz (Gain Relative to khz) l... db IN = P-P, f IN = MHz (Gain Relative to khz) l.. db IN = P-P, f IN = MHz (Gain Relative to khz) l 9 db IN = P-P, f IN = MHz (Gain Relative to khz) l db Filter Gain, S = IN = P-P, f IN = DC to khz.. db IN = P-P, f IN =.MHz (Gain Relative to khz) l.. db IN = P-P, f IN =.MHz (Gain Relative to khz) l.. db IN = P-P, f IN = MHz (Gain Relative to khz) l...9 db IN = P-P, f IN = MHz (Gain Relative to khz) l..9 db IN = P-P, f IN = MHz (Gain Relative to khz) l 9 db IN = P-P, f IN = MHz (Gain Relative to khz) l db Filter Gain, S = ± IN = P-P, f IN = DC to khz... db Filter Gain, = Ω OUT =. P-P, f IN = DC to khz, S = OUT =. P-P, f IN = DC to khz, S = OUT =. P-P, f IN = DC to khz, S = ±......9... db db db fb

ELECTRICAL CHARACTERISTICS LT- The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T A = C. Unless otherwise specified S = ( =, = ), = Ω, and R LOAD = k. PARAMETER CONDITIONS MIN TYP MAX UNITS Filter Gain Temperature Coeffi cient (Note ) f IN = khz, IN = P-P ppm/c Noise Noise BW = khz to MHz 9 μ RMS Distortion (Note ) MHz, P-P, R L = Ω, S = nd Harmonic rd Harmonic MHz, P-P, R L = Ω, S = nd Harmonic rd Harmonic Differential Output Swing Measured Between Pins and S = S =.. 9 9.. dbc dbc dbc dbc P-P DIFF P-P DIFF Input Bias Current Average of Pin and Pin 9 μa Input Referred Differential Offset = Ω S = S = S = ± = Ω S = S = S = ± Differential Offset Drift μ/ C Input Common Mode oltage (Note ) Differential Input = m P-P, S =.. = Ω S = S = ±.... Output Common Mode oltage (Note ) Differential Input = P-P, S = Pin = OPEN S = Common Mode oltage at Pin S = ± Output Common Mode Offset (with Respect to Pin ) S = S = S = ± Common Mode Rejection Ratio db oltage at MID (Pin ) S = S =... ± ± ± ± ± ± l... ± ± ± ± ± ±... m m m m m m m m m. MID Input Resistance l... kω OCM Bias Current OCM = MID = S / S = S = Power Supply Current S =, S = S = S = S = ± 9 ma ma ma ma Power Supply oltage l μa μa Note : Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note : This is the temperature coeffi cient of the internal feedback resistors assuming a temperature independent external resistor ( ). Note : The input common mode voltage is the average of the voltages applied to the external resistors ( ). Specifi cation guaranteed for Ω. Note : Distortion is measured differentially using a differential stimulus, The input common mode voltage, the voltage at Pin, and the voltage at Pin are equal to one half of the total power supply voltage. Note : Output common mode voltage is the average of the voltages at Pins and. The output common mode voltage is equal to the voltage applied to Pin. Note : The LTC- is guaranteed functional over the operating temperature range C to C. Note : The LTC- is guaranteed to meet C to C specifi cations and is designed, characterized and expected to meet the extended temperature limits, but is not tested at C and C. The LTI- is guaranteed to meet specifi ed performance from C to C. Note : The inputs are protected by back-to-back diodes. If the differential input voltage exceeds., the input current should be limited to less than ma. fb

LT- TYPICAL PERFORMANCE CHARACTERISTICS GAIN (db) Amplitude Response Passband Gain and Phase Passband Gain and Delay S = GAIN = T A = C. G GAIN (db) 9 GAIN PHASE S = GAIN = T A = C G 9 9 PHASE (DEG) GAIN (db) 9 DELAY GAIN S = GAIN = T A = C G DELAY (ns) GAIN (db) Passband Gain and Delay Output Impedance Common Mode Rejection Ratio GAIN DELAY S = GAIN = T A = C G DELAY (ns) OUTPUT IMPEDANCE (Ω) S = GAIN = T A = C.. G CMRR (db). IN = P-P S = GAIN = T A = C G PSRR (db). Power Supply Rejection Ratio S = IN = m P-P T A = C TO DIFFOUT G DISTORTION (db) 9. Distortion vs Frequency IN = P-P S = R L = Ω AT EACH OUTPUT GAIN = T A = C G DIFFERENTIAL INPUT, ND HARMONIC DIFFERENTIAL INPUT, RD HARMONIC SINGLE-ENDED INPUT, ND HARMONIC SINGLE-ENDED INPUT, RD HARMONIC fb

TYPICAL PERFORMANCE CHARACTERISTICS LT- DISTORTION (db) 9 Distortion vs Signal Level S = R L = Ω AT EACH OUTPUT GAIN = T A = C ND HARMONIC MHz INPUT RD HARMONIC MHz INPUT ND HARMONIC MHz INPUT INPUT LEEL ( P-P ) RD HARMONIC MHz INPUT G9 DISTORTION (db) 9 Distortion vs Signal Level S = ± R L = Ω AT EACH OUTPUT GAIN = T A = C ND HARMONIC, MHz INPUT RD HARMONIC, MHz INPUT ND HARMONIC, MHz INPUT RD HARMONIC, MHz INPUT INPUT LEEL ( P-P ) G DISTORTION COMPONENT (db) 9 Distortion vs Input Common Mode Level ND HARMONIC, S = RD HARMONIC, S = ND HARMONIC, S = RD HARMONIC, S = GAIN = R L = Ω AT EACH OUTPUT T A = C P-P MHz INPUT INPUT COMMON MODE OLTAGE RELATIE TO PIN () G DISTORTION COMPONENT (db) 9 Distortion vs Input Common Mode Level ND HARMONIC, S = RD HARMONIC, S = ND HARMONIC, S = RD HARMONIC, S = GAIN =, R L = Ω AT EACH OUTPUT T A = C, m P-P MHz INPUT INPUT COMMON MODE OLTAGE RELATIE TO PIN () G DISTORTION COMPONENT (db) Distortion vs Output Common Mode ND HARMONIC, S = RD HARMONIC, S = ND HARMONIC, S = RD HARMONIC, S = ND HARMONIC, S = ± RD HARMONIC, 9 S = ± P-P MHz INPUT GAIN =, R L = Ω AT EACH OUTPUT T A = C..... OLTAGE PIN TO PIN () G TOTAL SUPPLY CURRENT (ma) Total Supply Current vs Total Supply oltage T A = C T A = C T A = C TOTAL SUPPLY OLTAGE () OUT m/di OUT m/di IN IN m/di Transient Response ns/di DIFFERENTIAL GAIN = SINGLE-ENDED INPUT DIFFERENTIAL OUTPUT G G fb

LT- PIN FUNCTIONS IN and IN (Pins, ): Input Pins. Signals can be applied to either or both input pins through identical external resistors,. The DC gain from differential inputs to the differential outputs is Ω/. OCM (Pin ): Is the DC Common Mode Reference oltage for the nd Filter Stage. Its value programs the common mode voltage of the differential output of the filter. Pin is a high impedance input, which can be driven from an external voltage reference, or Pin can be tied to Pin on the PC board. Pin should be bypassed with a.μf ceramic capacitor unless it is connected to a ground plane. and (Pins, ): Power Supply Pins. For a single. or supply (Pin grounded) a quality.μf ceramic bypass capacitor is required from the positive supply pin (Pin ) to the negative supply pin (Pin ). The bypass should be as close as possible to the IC. For dual supply applications, bypass Pin to ground and Pin to ground with a quality.μf ceramic capacitor. OUT and OUT (Pins, ): Output Pins. Pins and are the filter differential outputs. Each pin can drive a Ω and/or pf load. MID (Pin ): The MID pin is internally biased at midsupply, see the Block Diagram section. For single supply operation, the MID pin should be bypassed with a quality.μf ceramic capacitor to Pin. For dual supply operation, Pin can be bypassed or connected to a high quality DC ground. A ground plane should be used. A poor ground will increase noise and distortion. Pin sets the output common mode voltage of the st stage of the filter. It has a.kω impedance, and it can be overridden with an external low impedance voltage source. BLOCK DIAGRAM IN IN OUT MID Ω OCM OP AMP k k Ω Ω OCM PROPRIETARY LOWPASS FILTER STAGE Ω Ω Ω IN IN OCM OUT BD fb

APPLICATIONS INFORMATION Interfacing to the LT- The LT- requires two equal external resistors,, to set the differential gain to Ω/. The inputs to the filter are the voltages IN and IN presented to these external components, Figure. The difference between IN and IN is the differential input voltage. The average of IN and IN is the common mode input voltage. Similarly, the voltages OUT and OUT appearing at Pins and of the LT- are the fi lter outputs. The difference between OUT and OUT is the differential output voltage. The average of OUT and OUT is the common mode output voltage. Figure illustrates the LT- operating with a single. supply and unity passband gain; the input signal is DC coupled. The common mode input voltage is., and the differential input voltage is P-P. The common mode LT- output voltage is., and the differential output voltage is P-P for frequencies below MHz. The common mode output voltage is determined by the voltage at Pin. Since Pin is shorted to Pin, the output common mode is the mid-supply voltage. In addition, the common mode input voltage can be equal to the mid-supply voltage of Pin (see the Distortion vs Input Common Mode Level graphs in the Typical Performance Characteristics section). Figure shows how to AC couple signals into the LT-. In this instance, the input is a single-ended signal. AC coupling allows the processing of single-ended or differential signals with arbitrary common mode levels. The.μF coupling capacitor and the Ω gain setting resistor form a high pass filter, attenuating signals below khz. Larger values of coupling capacitors will proportionally reduce this highpass db frequency...μf Ω IN OUT LT- IN.μF IN OUT Ω t IN Figure OUT OUT F t IN t IN.μF.μF Ω Ω.μF..μF LT- OUT OUT OUT OUT F Figure m P-P (DIFF) IN IN t IN IN pf Ω Ω pf.μf.μf LT- OUT OUT OUT OUT F t Figure fb

LT- APPLICATIONS INFORMATION In Figure the LT- is providing db of gain. The gain resistor has an optional pf in parallel to improve the passband fl atness near MHz. The common mode output voltage is set to. Use Figure to determine the interface between the LT- and a current output DAC. The gain, or transimpedance, is defined as A = OUT /I IN. To compute the transimpedance, use the following equation: A = R ( RR) ( Ω) By setting R R = Ω, the gain equation reduces to A = R(Ω). The voltage at the pins of the DAC is determined by R, R, the voltage on Pin and the DAC output current. Consider Figure with R = 9.9Ω and R = Ω. The voltage at Pin is.. The voltage at the DAC pins is given by: R DAC = PIN RR I IN R R RR = m I IN.Ω I IN is I IN or I IN. The transimpedance in this example is 9.Ω. Evaluating the LT- The low impedance levels and high frequency operation of the LT- require some attention to the matching networks between the LT- and other devices. The previous examples assume an ideal (Ω) source impedance and a large (kω) load resistance. Among practical examples where impedance must be considered is the evaluation of the LT- with a network analyzer. Figure is a laboratory setup that can be used to characterize the LT- using single-ended instruments with Ω source impedance and Ω input impedance. For a unity gain configuration the LT- requires a Ω source resistance yet the network analyzer output is calibrated for a Ω load resistance. The : transformer,.ω and Ω resistors satisfy the two constraints above. The transformer converts the single-ended source into a differential stimulus. Similarly, the output of the LT- will have lower distortion with larger load resistance yet the analyzer input is typically Ω. The : turns (: impedance) transformer and the two Ω resistors of Figure, present the output of the LT- with a Ω differential load, or the equivalent of Ω to ground at each output. The impedance seen by the network analyzer input is still Ω, reducing reflections in the cabling between the transformer and analyzer input. Differential and Common Mode oltage Ranges The differential amplifiers inside the LT- contain circuitry to limit the maximum peak-to-peak differential voltage through the fi lter. This limiting function prevents excessive power dissipation in the internal circuitry and provides output short-circuit protection. The limiting function begins to take effect at output signal levels above P-P and it becomes noticeable above. P-P. This is illustrated in Figure ; the LT- was confi gured with unity passband gain and the input of the filter was driven with a MHz signal. Because this voltage limiting takes place well before the output stage of the filter reaches the CURRENT OUTPUT DAC I IN R I IN R.μF R R..μF LT- OUT OUT NETWORK ANALYZER SOURCE Ω COILCRAFT TTWB- : Ω.Ω Ω..μF LT-.μF COILCRAFT TTWB-A : Ω Ω NETWORK ANALYZER INPUT Ω F F. Figure Figure fb

LT- APPLICATIONS INFORMATION OUTPUT LEEL (db) db COMPRESSION POINTS RD HARMONIC C ND HARMONIC C RD HARMONIC C ND HARMONIC, C C C MHz INPUT LEEL ( P-P ) F Figure. Output Level vs Input Level, Differential MHz Input, Gain = supply rails, the input/output behavior of the IC shown in Figure is relatively independent of the power supply voltage. The two amplifiers inside the LT- have independent control of their output common mode voltage (see the Block Diagram section). The following guidelines will optimize the performance of the fi lter. Pin must be bypassed to an AC ground with a.μf or larger capacitor. Pin can be driven from a low impedance source, provided it remains at least. above and at least. below. An internal resistor divider sets the voltage of Pin. While the internal k resistors are well matched, their absolute value can vary by ±%. This should be taken into consideration when connecting an external resistor network to alter the voltage of Pin. Pin can be shorted to Pin for simplicity. If a different common mode output voltage is required, connect Pin to a voltage source or resistor network. For and. supplies the voltage at Pin must be less than or equal to the mid supply level. For example, voltage (Pin ). on a single. supply. For power supply voltages higher than. the voltage at Pin should be within the voltage of Pin to the voltage of Pin. Pin is a high impedance input. The LT- was designed to process a variety of input signals including signals centered around the mid-supply voltage and signals that swing between ground and a positive voltage in a single supply system (Figure ). The range of allowable input common mode voltage (the average of IN and IN in Figure ) is determined by the power supply level and gain setting (see Distortion vs Input Common Mode Level in the Typical Performance Characteristics section). Common Mode DC Currents In applications like Figure and Figure where the LT- not only provides lowpass filtering but also level shifts the common mode voltage of the input signal, DC currents will be generated through the DC path between input and output terminals. Minimize these currents to decrease power dissipation and distortion. Consider the application in Figure. Pin sets the output common mode voltage of the st differential amplifi er inside the LT- (see the Block Diagram section) at.. Since the input common mode voltage is near, there will be approximately a total of. drop across the series combination of the internal Ω feedback resistor and the external Ω input resistor. The resulting.ma common mode DC current in each input path, must be absorbed by the sources IN and IN. Pin sets the common mode output voltage of the nd differential amplifier inside the LT-, and therefore sets the common mode output voltage of the filter. Since, in the example of Figure, Pin differs from Pin by., an additional.ma (.ma per side) of DC current will flow in the resistors coupling the st differential amplifier output stage to fi lter output. Thus, a total of 9.9mA is used to translate the common mode voltages. A simple modification to Figure will reduce the DC common mode currents by %. If Pin is shorted to Pin the common mode output voltage of both op amp stages will be and the resulting DC current will be ma. Of course, by AC coupling the inputs of Figure, the common mode DC current can be reduced to.ma. fb 9

LT- APPLICATIONS INFORMATION Noise The noise performance of the LT- can be evaluated with the circuit of Figure. Given the low noise output of the LT- and the db attenuation of the transformer coupling network, it is necessary to measure the noise floor of the spectrum analyzer and subtract the instrument noise from the filter noise measurement. Example: With the IC removed and the Ω resistors grounded, Figure, measure the total integrated noise (e S ) of the spectrum analyzer from khz to MHz. With the IC inserted, the signal source ( IN ) disconnected, and the input resistors grounded, measure the total integrated noise out of the filter (e O ). With the signal source connected, set the frequency to MHz and adjust the amplitude until IN measures m P-P. Measure the output amplitude, OUT, and compute the passband gain A = OUT / IN. Now compute the input referred integrated noise (e IN ) as: e IN = (e O ) (e S ) A Table lists the typical input referred integrated noise for various values of. Figure is plot of the noise spectral density as a function of frequency for an LT- using the fi xture of Figure (the instrument noise has been subtracted from the results). Table. Noise Performance PASSBAND GAIN (/) INPUT REFERRED INTEGRATED NOISE khz TO MHz INPUT REFERRED INTEGRATED NOISE khz TO MHz Ω μ RMS μ RMS Ω μ RMS 9μ RMS Ω 9μ RMS 9μ RMS The noise at each output is comprised of a differential component and a common mode component. Using a transformer or combiner to convert the differential outputs to single-ended signal rejects the common mode noise and gives a true measure of the S/N achievable in the system. Conversely, if each output is measured individually and the NOISE DENSITY (n RMS / Hz) IN...μF LT-.μF Figure NOISE DENSITY, GAIN = x NOISE DENSITY, GAIN = x INTEGRATED NOISE, GAIN = x INTEGRATED NOISE, GAIN = x Figure. Input Referred Noise, Gain = noise power added together, the resulting calculated noise level will be higher than the true differential noise. Power Dissipation The LT- amplifiers combine high speed with largesignal currents in a small package. There is a need to ensure that the die junction temperature does not exceed C. The LT- package has Pin fused to the lead frame to enhance thermal conduction when connecting to a ground plane or a large metal trace. Metal trace and plated through-holes can be used to spread the heat generated by the device to the backside of the PC board. For example, on a /" FR- board with oz copper, a total of square millimeters connected to Pin of the LT- ( square millimeters on each side of the PC board) will result in a thermal resistance, θ JA, of about C/W. Without the extra metal trace connected to the pin to provide a heat sink, the thermal resistance will be around C/W. Table can be used as a guide when considering thermal resistance. Ω Ω COILCRAFT TTWB- :.. F SPECTRUM ANALYZER INPUT INTEGRATED NOISE (μ) Ω F fb

APPLICATIONS INFORMATION Table. LT- SO- Package Thermal Resistance COPPER AREA TOPSIDE (mm ) BACKSIDE (mm ) BOARD AREA (mm ) THERMAL RESISTANCE (JUNCTION-TO-AMBIENT) C/W C/W 9 C/W C/W C/W Junction temperature, T J, is calculated from the ambient temperature, T A, and power dissipation, P D. The power dissipation is the product of supply voltage, S, and supply current, I S. Therefore, the junction temperature is given by: T J = T A (P D θ JA ) = T A ( S I S θ JA ) where the supply current, I S, is a function of signal level, load impedance, temperature and common mode voltages. LT- For a given supply voltage, the worst-case power dissipation occurs when the differential input signal is maximum, the common mode currents are maximum (see the Applications Information section regarding common mode DC currents), the load impedance is small and the ambient temperature is maximum. To compute the junction temperature, measure the supply current under these worst-case conditions, estimate the thermal resistance from Table, then apply the equation for T J. For example, using the circuit in Figure with a DC differential input voltage of m, a differential output voltage of, no load resistance and an ambient temperature of C, the supply current (current into Pin ) measures ma. Assuming a PC board layout with a mm copper trace, the θ JA is C/W. The resulting junction temperature is: T J = T A (P D θ JA ) = (. ) = C When using higher supply voltages or when driving small impedances, more copper may be necessary to keep T J below C. PACKAGE DESCRIPTION S Package -Lead Plastic Small Outline (Narrow. Inch) (Reference LTC DWG # --). BSC. ±..9.9 (..) NOTE. MIN. ±... (.9.9).. (..9) NOTE. ±. TYP RECOMMENDED SOLDER PAD LAYOUT.. (..).. (..) TYP..9 (..).. (..)....9 (..) (..) NOTE: INCHES TYP. DIMENSIONS IN (MILLIMETERS). DRAWING NOT TO SCALE. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED." (.mm). (.) BSC SO Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. fb

LT- TYPICAL APPLICATION Dual Matched I and Q Lowpass Filter and ADC (Typical Phase Matching ± Degree).μF CMA.μF.μF Ω I.μF Ω LT- Ω Ω.pF.pF.pF INA.μF LTC99 Ω Q.μF Ω LT- Ω Ω GAIN = Ω/.pF.pF.pF CMB INB.μF TA RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LTC - khz Linear Phase Lowpass Filter Continuous Time, SO Package, Fully Differential LTC- Low Noise,.MHz Lowpass Filter Continuous Time, SO Package LT ery Low Noise, High Frequency Filter Building Block.n/ Hz Op Amp, MSOP Package, Fully Differential LT ery Low Noise, th Order Building Block Lowpass and Bandpass Filter Designs Up to MHz, Differential Outputs LT99-X Low Distortion, Low Noise Differential Amplifi er/adc Driver Fixed Gain of db, db and db LT99 Low Distortion, Low Noise Differential Amplifi er/adc Driver Adjustable, Low Power, S =. to. LT-. ery Low Noise Differential Amplifi er and.mhz db S/N with Supply, SO- Lowpass Filter LT- ery Low Noise Differential Amplifi er and MHz db S/N with Supply, SO- Lowpass Filter LT- ery Low Noise Differential Amplifi er and MHz db S/N with Supply, SO- Lowpass Filter LT- ery Low Noise Differential Amplifi er and MHz Lowpass Filter db S/N with Supply, SO- fb LT 9 RE B PRINTED IN USA Linear Technology Corporation McCarthy Blvd., Milpitas, CA 9- () -9 FAX: () - www.linear.com LINEAR TECHNOLOGY CORPORATION