DESCRIPTIO FEATURES APPLICATIO S. LT MHz Current Feedback Amplifier TYPICAL APPLICATIO

Transcription

1 MHz Current Feedback Amplifier FEATRES MHz Bandwidth at A V = V/µs Slew Rate Wide Supply Range: ±V to ±V mv Input Offset Voltage µa Input Bias Current MΩ Input Resistance 7ns Settling Time to.% ma Output Current ma Quiescent Current Available in -Lead Plastic DIP and SO Packages APPLICATIO S Video Amplifiers Buffers IF and RF Amplification Cable Drivers -, -, -Bit Data Acquisition Systems DESCRIPTIO The LT 3 is a MHz current feedback amplifier with very good DC characteristics. The LT3 s high slew rate, V/µs, wide supply range, ±V, and large output drive, ±ma, make it ideal for driving analog signals over double-terminated cables. The current feedback amplifier has high gain bandwidth at high gains, unlike conventional op amps. The LT3 comes in the industry standard pinout and can upgrade the performance of many older products. The LT3 is manufactured on Linear Technology s proprietary complementary bipolar process., LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATIO Video Cable Driver Voltage Gain vs Frequency V IN k LT3 R F k CABLE VOLTAGE GAIN (db) 3 = = 33 = = 7 = MHz GAIN BANDWIDTH k R A V = F AT AMPLIFIER OTPT db LESS AT LT3 TA k M M M G FREQENCY (Hz) LT3 TPC

2 ABSOLTE AXI RATI GS (Note ) W W W Supply Voltage... ±V Differential Input Voltage... ±V Input Voltage... Equal to Supply Voltage Output Short Circuit Duration (Note )...Continuous Operating Temperature Range LT3M (OBSOLETE)... C to C LT3C... C to 7 C Storage Temperature Range... C to C Junction Temperature Plastic Package... C Junction Temperature Ceramic Package (OBSOLETE)... 7 C Lead Temperature (Soldering, sec.)... 3 C PACKAGE/ORDER I FOR NLL IN IN V 3 N PACKAGE -LEAD PLASTIC DIP TOP VIEW 7 T J MAX = C, θ JA = C/W(N) T J MAX = C, θ JA = C/W(S) J PACKAGE -LEAD CERAMIC DIP T JMAX = 7 C, θ JA = CW (J) SHTDOWN V OT NLL S PACKAGE -LEAD PLASTIC SO W OBSOLETE PACKAGE Consider the N or S for Alternative Source ATIO ORDER PART NMBER LT3CN LT3CS S PART MARKING 3 LT3CJ LT3MJ Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS, T A = C, unless otherwise noted. LT3M/C SYMBOL PARAMETER CONDITIONS MIN TYP MAX NITS V OS Input Offset Voltage V CM = V ± ±3 mv I IN Noninverting Input Current V CM = V ± ±3 µa I IN Inverting Input Current V CM = V ± ±3 µa e n Input Noise Voltage Density f = khz, R F = k, = Ω 3.3 nv/ Hz i n Input Noise Current Density f = khz, R F = k, = Ω. pa/ Hz R IN Input Resistance V IN = ±V MΩ C IN Input Capacitance. pf Input Voltage Range ± ± V CMRR Common Mode Rejection Ratio V CM = ±V 3 db Inverting Input Current Common Mode Rejection V CM = ±V 3 na/v PSRR Power Supply Rejection Ratio V S = ±.V to ±V db Noninverting Input Current Power Supply Rejection V S = ±.V to ±V na/v Inverting Input Current Power Supply Rejection V S = ±.V to ±V na/v A V Large Signal Voltage Gain R LOAD = Ω, = ±V 7 9 db R OL Transresistance, / I IN R LOAD = Ω, = ±V. MΩ Maximum Output Voltage Swing R LOAD = Ω ± ± V I OT Maximum Output Current R LOAD = Ω ma SR Slew Rate R F =.k, =.k (Note 3) 3 V/µs BW Bandwidth R F = k, = k, = mv MHz

3 ELECTRICAL CHARACTERISTICS, T A = C, unless otherwise noted. LT3M/C SYMBOL PARAMETER CONDITIONS MIN TYP MAX NITS t r Rise Time R F =.k, =.k, = V. ns t PD Propagation Delay R F =.k, =.k, = V. ns Overshoot R F =.k, =.k, = V % t s Settling Time,.% R F = k, = k, = V 7 ns Differential Gain R F = k, = k, R L = Ω. % Differential Phase R F = k, = k, R L = Ω. Deg R OT Open-Loop Output Resistance =, I OT = 3 Ω I S Supply Current V IN = V ma Supply Current, Shutdown Pin Current = µa ma The denotes the specifications which apply over the full operating temperature range, otherwise specifications are at, V CM = V, C T A 7 C, unless otherwise noted. LT3C SYMBOL PARAMETER CONDITIONS MIN TYP MAX NITS V OS Input Offset Voltage V CM = V ± ±3 mv I IN Noninverting Input Current V CM = V ± ±3 µa I IN Inverting Input Current V CM = V ± ±3 µa R IN Input Resistance V IN = ±V MΩ Input Voltage Range ± ± V CMRR Common Mode Rejection Ratio V CM = ±V 3 db Inverting Input Current Common Mode Rejection V CM = ±V 3 na/v PSRR Power Supply Rejection Ratio V S = ±.V to ±V db Noninverting Input Current Power Supply Rejection V S = ±.V to ±V na/v Inverting Input Current Power Supply Rejection V S = ±.V to ±V na/v A V Large-Signal Voltage Gain R LOAD = Ω, = ±V 7 9 db R OL Transresistance, / I IN R LOAD = Ω, = ±V. MΩ Maximum Output Voltage Swing R LOAD = Ω ± ± V I OT Maximum Output Current R LOAD = Ω ma I S Supply Current V IN = V ma Supply Current, Shutdown Pin Current = µa ma 3

4 ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range, otherwise specifications are at, V CM = V, C T A C, unless otherwise noted. LT3M SYMBOL PARAMETER CONDITIONS MIN TYP MAX NITS V OS Input Offset Voltage V CM = V ± ± mv I IN Noninverting Input Current V CM = V ± ± µa I IN Inverting Input Current V CM = V ± ± µa R IN Input Resistance V IN = ±V MΩ Input Voltage Range ± ± V CMRR Common Mode Rejection Ratio V CM = ±V 3 db Inverting Input Current Common Mode Rejection V CM = ±V 3 na/v PSRR Power Supply Rejection Ratio V S = ±.V to ±V db Noninverting Input Current Power Supply Rejection V S = ±.V to ±V na/v Inverting Input Current Power Supply Rejection V S = ±.V to ±V na/v A V Large-Signal Voltage Gain R LOAD = Ω, = ±V 7 9 db R OL Transresistance, / I IN R LOAD = Ω, = ±V. MΩ Maximum Output Voltage Swing R LOAD = Ω ±7 ± V I OT Maximum Output Current R LOAD = Ω 3 ma I S Supply Current V IN = V ma Supply Current, Shutdown Pin Current = µa ma Note : Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note : A heat sink may be required. Note 3: Noninverting operation, = ±V, measured at ±V.

5 TYPICAL PERFOR A CE CHARACTERISTICS W SPPLY CRRENT (ma) Supply Current vs Supply Voltage, Supply Current vs Supply Voltage Output Short Circuit-Current vs V IN = (Operating) (Shutdown) Temperature C C C SPPLY CRRENT (ma) 3 PIN = V C C C OTPT SHORT CIRCIT CRRENT (ma) SPPLY VOLTAGE (±V) LT3 TPC SPPLY VOLTAGE (±V) LT3 TPC3 CASE TEMPERATRE ( C) LT3 TPC COMMON MODE RANGE (V) V 3 3 Input Common Mode Limit vs Temperature I B vs Common Mode Voltage I B vs Common Mode Voltage V = V S V = ±V S V = V S V = ±V S V 7 I B (µa) 3 3 C C C V = ±V S I B (µa) C C C TEMPERATRE ( C) LT3 TPC COMMON MODE VOLTAGE (V) LT3 TPC COMMON MODE VOLTAGE (V) LT3 TPC7 V OS (mv) Output Voltage Swing vs Output Voltage Swing vs V OS vs Common Mode Voltage Load Resistor Supply Voltage C C C OTPT VOLTAGE SWING (V) V S = ±V C C, C C, C C OTPT VOLTAGE SWING (V) C C C C C C COMMON MODE VOLTAGE (V) LT3 TPC LOAD RESISTOR ( Ω) LT3 TPC9 SPPLY VOLTAGE (±V) LT3 TPC

6 TYPICAL PERFOR A CE CHARACTERISTICS 3dB BANDWIDTH (MHz) W 3dB Bandwidth vs 3dB Bandwidth vs Minimum Feedback Resistor vs Feedback Resistor Supply Voltage Voltage Gain 9 A V = ; R F = R L = Ω ; NO CAPACITIVE LOAD FEEDBACK RESISTOR (k Ω) 3dB BANDWIDTH (MHz) R F = 9 A V = R L = Ω T A = C 7 R F = 7 R F = k R F =.k 3 R F = k SPPLY VOLTAGE ( ± V) FEEDBACK RESISTOR ( Ω ) 9 7 db PEAKING R L = db PEAKING 3 3 VOLTAGE GAIN (V/V) LT3 TPC LT3 TPC LT3 TPC3 CAPACITIVE LOAD (pf) SPOT NOISE (nv/ Hz OR pa/ Hz ) k k Maximum Capacitive Load vs Open-Loop Voltage Gain vs Feedback Resistor Load Resistor Transimpedance vs Load Resistor A V = ; R F = R L = ; PEAKING < db 3 FEEDBACK RESISTOR (k Ω) LT3 TPC OPEN LOOP VOLTAGE GAIN (db) 9 7 C C C V O = ± V LOAD RESISTOR ( Ω) LT3 TPC LOAD RESISTOR ( Ω) Spot Noise Voltage and Current vs Power Supply Rejection vs Frequency Frequency Output Impedance vs Frequency in e n in k k FREQENCY (Hz) LT3 TPC7 POWER SPPLY REJECTION (db) NEGATIVE POSITIVE FREQENCY (Hz) V S = ±V R F = k k k M M M LT3 TPC TRANSIMPEDANCE (M Ω ) MAGNITDE OF OTPT IMPEDANCE ( Ω ) 9 V O = ± V 7 3. R F = = 3k C C C R F = = k FREQENCY (Hz) LT3 TPC. k k M M M LT3 TPC9

7 TYPICAL PERFOR A CE CHARACTERISTICS VOLTAGE GAIN (db) 3 M W Voltage Gain and Phase vs Total Harmonic Distortion vs nd and 3rd Harmonic Frequency Frequency Distortion vs Frequency R F = = k 3 GAIN 9 R L= Ω R L k PHASE R L k R = L Ω 9 3 M M G FREQENCY (Hz) LT3 TPC PHASE SHIFT (DEGREES) TOTAL HARMONIC DISTORTION (%).. V O = 7VRMS R L = Ω R F = =k THD. k k k FREQENCY (Hz) LT3 TPC DISTORTION (dbc) 3 7 V O = V P-P R L = R F = k A V = db FREQENCY (MHz) LT3 ND 3RD LT3 TPC OTPT STEP (V) Noninverting Amplifier Settling Noninverting Amplifier Settling Inverting Amplifier Settling Time to mv vs Output Step Time to mv vs Output Step Time vs Output Step A V = R F = k R L = k TO mv TO mv OTPT STEP (V) A V = R F = k R L = k TO mv TO mv OTPT STEP (V) A V = R F = k R L = k TO mv TO mv TO mv TO mv SETTLING TIME (ns) LT3 TPC3 SETTLING TIME ( µ s) LT3 TPC SETTLING TIME (ns) LT3 TPC APPLICATIO S I FOR Current Feedback Basics ATIO W The small-signal bandwidth of the LT3, like all current feedback amplifiers, isn t a straight inverse function of the closed-loop gain. This is because the feedback resistors determine the amount of current driving the amplifier s internal compensation capacitor. In fact, the amplifier s feedback resistor (R F ) from output to inverting input works with internal junction capacitances of the LT3 to set the closed-loop bandwidth. Even though the gain set resistor ( ) from inverting input to ground works with R F to set the voltage gain just like it does in a voltage feedback op amp, the closed-loop bandwidth does not change. This is because the equivalent gain bandwidth product of the current feedback amplifier is set by the Thevenin equivalent resistance at the inverting input and the internal compensation capacitor. By keeping R F constant and changing the gain with, the Thevenin resistance changes by the same amount as the change in gain. As a result, the net closed-loop bandwidth of the LT3 remains the same for various closed-loop gains. 7

8 APPLICATIO S I FOR ATIO W The curve on the first page shows the LT3 voltage gain versus frequency while driving Ω, for five gain settings from to. The feedback resistor is a constant k and the gain resistor is varied from infinity to Ω. Shown for comparison is a plot of the fixed MHz gain bandwidth limitation that a voltage feedback amplifier would have. It is obvious that for gains greater than one, the LT3 provides 3 to times more bandwidth. It is also evident that second order effects reduce the bandwidth somewhat at the higher gain settings. Feedback Resistor Selection Because the feedback resistor determines the compensation of the LT3, bandwidth and transient response can be optimized for almost every application. To increase the bandwidth when using higher gains, the feedback resistor (and gain resistor) can be reduced from the nominal k value. The Minimum Feedback Resistor versus Voltage Gain curve shows the values to use for ±V supplies. Larger feedback resistors can also be used to slow down the LT3 as shown in the 3dB Bandwidth versus Feedback Resistor curve. Capacitive Loads The LT3 can be isolated from capacitive loads with a small resistor (Ω to Ω) or it can drive the capacitive load directly if the feedback resistor is increased. Both techniques lower the amplifier s bandwidth about the same amount. The advantage of resistive isolation is that the bandwidth is only reduced when the capacitive load is present. The disadvantage of resistor isolation is that resistive loading causes gain errors. Because the DC accuracy is not degraded with resistive loading, the desired way of driving capacitive loads, such as flash converters, is to increase the feedback resistor. The Maximum Capacitive Load versus Feedback Resistor curve shows the value of feedback resistor and capacitive load that gives db of peaking. For less peaking, use a larger feedback resistor. Power Supplies The LT3 may be operated with single or split supplies as low as ±V (V total) to as high as ±V (3V total). It is not necessary to use equal value split supplies, however, the offset voltage will degrade about 3µV per volt of mismatch. The internal compensation capacitor decreases with increasing supply voltage. The 3dB Bandwidth versus Supply Voltage curve shows how this affects the bandwidth for various feedback resistors. Generally, the bandwidth at ±V supplies is about half the value it is at ±V supplies for a given feedback resistor. The LT3 is very stable even with minimal supply bypassing, however, the transient response will suffer if the supply rings. It is recommended for good slew rate and settling time that.7µf tantalum capacitors be placed within. inches of the supply pins. Input Range The noninverting input of the LT3 looks like a M resistor in parallel with a 3pF capacitor until the common mode range is exceeded. The input impedance drops somewhat and the input current rises to about µa when the input comes too close to the supplies. Eventually, when the input exceeds the supply by one diode drop, the base collector junction of the input transistor forward biases and the input current rises dramatically. The input current should be limited to ma when exceeding the supplies. The amplifier will recover quickly when the input is returned to its normal common mode range unless the input was over mv beyond the supplies, then it will take an extra ns. Offset Adjust Output offset voltage is equal to the input offset voltage times the gain plus the inverting input bias current times the feedback resistor. For low gain applications (3 or less) a kω pot connected to Pins and with wiper to V will trim the inverting input current (±µa) to null the output; it does not change the offset voltage very much. If the LT3 is used in a high gain application, where input offset voltage is the dominate error, it can be nulled by pulling approximately µa from Pin or. The easy way to do this is to use a kω pot between Pin and with a k resistor from the wiper to ground for V supply applications. se a 7k resistor when operating on a V supply.

9 APPLICATIO S I FOR Shutdown ATIO W Pin activates a shutdown control function. Pulling more than ma from Pin drops the supply current to less than 3mA, and puts the output into a high impedance state. The easy way to force shutdown is to ground Pin, using an open collector (drain) logic stage. An internal resistor limits current, allowing direct interfacing with no additional parts. When Pin is open, the LT3 operates normally. Output Slew Rate of V/µs Slew Rate The slew rate of a current feedback amplifier is not independent of the amplifier gain configuration the way it is in a traditional op amp. This is because the input stage and the output stage both have slew rate limitations. Inverting amplifiers do not slew the input and are therefore limited only by the output stage. High gain, noninverting amplifiers are similar. The input stage slew rate of the LT3 is about 3V/µs before it becomes nonlinear and is enhanced by the normally reverse-biased emitters on the input transistors. The output slew rate depends on the size of the feedback resistors. The peak output slew rate is about V/µs with a k feedback resistor and drops proportionally for larger values. At an output slew rate of V/µs or more, the transistors in the mirror circuits will begin to saturate due to the large feedback currents. This causes the output to have slew induced overshoot and is somewhat unusual looking; it is in no way harmful or dangerous to the device. The photos show the LT3 in a noninverting gain of three (R F = k, = Ω) with a V peak-to-peak output slewing at V/µs, V/µs and V/µs. Output Slew Rate of V/µs 3 A 3 A Output Slew Rate at V/µs Shows Aberrations (See Text) Settling Time The Inverting Amplifier Settling Time versus Output Step curve shows that the LT3 will settle to within mv of final value in less than ns for all output changes of V or less. When operated as an inverting amplifier there is less than µv of thermal settling in the amplifier. However, when operating the LT3 as a noninverting amplifier, there is an additional thermal settling component that is about µv for every volt of input common mode change. So a noninverting gain of one amplifier will 3 A3 9

10 APPLICATIO S I FOR have about.mv thermal tail on a V step. nfortunately, reducing the input signal and increasing the gain always results in a thermal tail of about the same amount for a given output step. For this reason we show separate graphs of mv and mv non-inverting amplifier settling times. Just as the bandwidth of the LT3 is fairly constant for various closed-loop gains, the settling time remains constant as well. Adjustable Gain Amplifier ATIO W To make a variable gain amplifier with the LT3, vary the value of. The implementation of can be a pot, a light controlled resistor, a FET, or any other low capacitance variable resistor. The value of R F should not be varied to change the gain. If R F is changed, then the bandwidth will be reduced at maximum gain and the circuit will oscillate when R F is very small. Accurate Bandwidth Limiting the LT3 It is very common to limit the bandwidth of an op amp by putting a small capacitor in parallel with R F. DO NOT PT A SMALL CAPACITOR FROM THE INVERTING INPT OF A CRRENT FEEDBACK AMPLIFIER TO ANYWHERE ELSE, ESPECIALLY NOT TO THE OTPT. The capacitor on the inverting input will cause peaking or oscillations. If you need to limit the bandwidth of a current feedback amplifier, use a resistor and capacitor at the noninverting input (R and C). This technique will also cancel (to a degree) the peaking caused by stray capacitance at the inverting input. nfortunately, this will not limit the output noise the way it does for the op amp. V IN R C LT3 V IN LT3 R = 3Ω C = pf BW = MHz R F R F LT3 TA Adjustable Bandwidth Amplifier LT3 TA3 Because the resistance at the inverting input determines the bandwidth of the LT3, an adjustable bandwidth circuit can be made easily. The gain is set as before with R F and ; the bandwidth is maximum when the variable resistor is at a minimum. Current Feedback Amplifier Integrator Since we remember that the inverting input wants to see a resistor, we can add one to the standard integrator circuit. This generates a new summing node where we can apply capacitive feedback. The LT3 integrator has excellent large signal capability and accurate phase shift at high frequencies. V IN LT3 V IN = scr LT3 k R F V IN R R F k C LT3 TA LT3 TA

11 APPLICATIO S I FOR Summing Amplifier (DC Accurate) ATIO W The summing amplifier is easily made by adding additional inputs to the basic inverting amplifier configuration. The LT3 has no I OS spec because there is no correlation between the two input bias currents. Therefore, we will not improve the DC accuracy of the inverting amplifier by putting in the extra resistor in the noninverting input. V I V I V In R G R G R n G LT3 = RF R F ( ) V I V V I In RGn LT3 TA7 inverting input (A) senses the shield and the non-inverting input (A) senses the center conductor. Since this amplifier does not load the cable (take care to minimize stray capacitance) and it rejects common mode hum and noise, several amplifiers can sense the signal with only one termination at the end of the cable. The design equations are simple. Just select the gain you need (it should be two or more) and the value of the feedback resistor (typically k) and calculate and. The gain can be tweaked with and the CMRR with if needed. The bandwidth of the noninverting input signal is not reduced by the presence of the other amplifier, however, the inverting input signal bandwidth is reduced since it passes two amplifiers. The CMRR is good at high frequencies because the bandwidth of the amplifiers are about the same even though they do not necessarily operate at the same gain. Difference Amplifier k R F k k R F k The LT3 difference amplifier delivers excellent performance if the source impedance is very low. This is because the common mode input resistance is only equal to R F. A LT3 A LT3 V IN V IN V V R V F OT = (V V) (R F ) Video Instrumentation Amplifier LT3 LT3 TA This instrumentation amplifier uses two LT3s to increase the input resistance to well over M. This makes an excellent loop through or cable sensing amplifier if the R F OPTIONAL TRIM FOR CMRR = G (V IN VIN ) R R F = R F ; = (G ) R F ; = F G TRIM GAIN (G) WITH ; TRIM CMRR WITH Cable Driver LT3 TA9 The cable driver circuit is shown on the front page. When driving a cable it is important to properly terminate both ends if even modest high frequency performance is required. The additional advantage of this is that it isolates the capacitive load of the cable from the amplifier so it can operate at maximum bandwidth.

12 TYPICAL APPLICATIO ma Output Current Video Amp V V IN V LT3 IN LT Ω BIAS OT V k V k R f = k TO STABILIZE CIRCIT DIFFERENTIAL GAIN = % DIFFERENTIAL PHASE = LT3 TA W SI PLIFIED SCHE ATIC W 7 k BIAS k 3 BIAS LT3 TA

13 PACKAGE DESCRIPTIO J Package -Lead CERDIP (Narrow.3 Inch, Hermetic) (Reference LTC DWG # --).. (.3.) FLL LEAD OPTION.3 BSC (7. BSC) CORNER LEADS OPTION ( PLCS).3. (..3) HALF LEAD OPTION. (.7) MIN. (.3) RAD TYP. (.7) MAX (. 7.7). (.) MAX.. (.3.).. (.3.7) NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS.. (.3.).. (.3.). (.) BSC. 3.7 MIN J OBSOLETE PACKAGE 3

14 PACKAGE DESCRIPTIO N Package -Lead PDIP (Narrow.3 Inch) (Reference LTC DWG # --).* (.) MAX 7. ±.* (.77 ±.3) (7..).. (.3.).3 ±. (3.3 ±.7).. (.3.3) ( ). (.) TYP. (.) BSC NOTE: INCHES. DIMENSIONS ARE MILLIMETERS *THESE DIMENSIONS DO NOT INCLDE MOLD FLASH OR PROTRSIONS. MOLD FLASH OR PROTRSIONS SHALL NOT EXCEED. INCH (.mm). (3.) MIN. ±.3 (.7 ±.7). (.) MIN N

15 PACKAGE DESCRIPTIO S Package -Lead Plastic Small Outline (Narrow. Inch) (Reference LTC DWG # --). BSC. ± (..) NOTE 3 7. MIN. ±... (.79.97)..7 (3. 3.9) NOTE 3.3 ±. TYP RECOMMENDED SOLDER PAD LAYOT 3.. (.3.).. (..) TYP.3.9 (.3.7).. (..).. (..7) NOTE: INCHES. DIMENSIONS IN (MILLIMETERS)..9 (.3.3) TYP. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLDE MOLD FLASH OR PROTRSIONS. MOLD FLASH OR PROTRSIONS SHALL NOT EXCEED." (.mm). (.7) BSC SO 33 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.

16 RELATED PARTS PART NMBER DESCRIPTION COMMENTS LT ma/mhz Current Feedback Amplifier 9V/µs, Shutdown LT39 MHz Current Feedback Amplifier V/µs,.mA Supply Current, SOT-3 Package LT97 Dual ma, MHz Current Feedback Amplifier 9V/µs, 7mA Supply Current LT/LT Single/Dual Programmable Supply Current, Rail-to-Rail C-Load TM Stable, MHz, 7V/µs Output C-Load is a trademark of Linear Technology Corporation. LT/LT REV B PRINTED IN SA Linear Technology Corporation 3 McCarthy Blvd., Milpitas, CA () 3-9 FAX: () LINEAR TECHNOLOGY CORPORATION 99