Triple 130 MHz Current Feedback Amplifier Features General Description # Triple amplifier topology # 130 MHz b 3 dB bandwidth (AV e a 2) # 180 MHz b 3 dB bandwidth (AV e a 1) # Wide supply range, g 2V to g 15V # 80 mA output current (peak) # Low cost # 1500 V/ms slew rate # Input common mode range to within 1.5V of supplies # 35 ns settling time to 0.1% # Available in single (EL2160C), dual (EL2260C), and quad (EL2460C) form The EL2360C is a triple current-feedback operational amplifier which achieves a b 3 dB bandwidth of 130 MHz at a gain of a 2. Built using the Elantec proprietary monolithic complementary bipolar process, these amplifiers use current mode feedback to achieve more bandwidth at a given gain than a conventional voltage feedback amplifier. Applications # # # # # # RGB amplifiers Video amplifiers Cable driver Test equipment amplifiers Current to voltage converters Video broadcast equipment EL2360C EL2360C The EL2360C is designed to drive a double terminated 75X coax cable to video levels. It’s fast slew rate of 1500 V/ms, combined with the triple amplifier topology, makes its ideal for RGB video applications. This amplifier can operate on any supply voltage from 4V ( g 2V) to 33V ( g 16.5V), yet consume only 8 mA per amplifier at any supply voltage. The EL2360C is available in 16-pin PDIP and SOIC packages. For Single, Dual, or Quad applications, consider the EL2160C, EL2260C, or EL2460C all in industry standard pin outs. For Single applications with a power down feature, consider the EL2166C. Connection Diagram EL2360C SOIC, P-DIP Packages Ordering Information Part No. Temp. Range Package Outline Ý EL2360CN b 40§ C to a 85§ C 16 b Pin PDIP MDP0031 EL2360CS b 40§ C to a 85§ C 16 b Pin SOIC MDP0027 Note: All information contained in this data sheet has been carefully checked and is believed to be accurate as of the date of publication; however, this data sheet cannot be a ‘‘controlled document’’. Current revisions, if any, to these specifications are maintained at the factory and are available upon your request. We recommend checking the revision level before finalization of your design documentation. © 1996 Elantec, Inc. June 1996 Rev A 2360 – 1 Top View EL2360C Triple 130 MHz Current Feedback Amplifier Absolute Maximum Ratings (TA e 25§ C) Voltage between VS a and VSb Common-Mode Input Voltage Differential Input Voltage Current into a IN or bIN Internal Power Dissipation a 33V VSb to VS a g 6V g 10 mA See Curves g 50 mA Output Current (continuous) Operating Ambient Temperature Range Operating Junction Temperature Storage Temperature Range b 40§ C to a 85§ C 150§ C b 65§ C to a 150§ C Important Note: All parameters having Min/Max specifications are guaranteed. The Test Level column indicates the specific device testing actually performed during production and Quality inspection. Elantec performs most electrical tests using modern high-speed automatic test equipment, specifically the LTX77 Series system. Unless otherwise noted, all tests are pulsed tests, therefore TJ e TC e TA. Test Level I II III IV V Test Procedure 100% production tested and QA sample tested per QA test plan QCX0002. 100% production tested at TA e 25§ C and QA sample tested at TA e 25§ C , TMAX and TMIN per QA test plan QCX0002. QA sample tested per QA test plan QCX0002. Parameter is guaranteed (but not tested) by Design and Characterization Data. Parameter is typical value at TA e 25§ C for information purposes only. Parameter Typ Max Test Level Units VS e g 5V, g 15V 2 10 I mV Description Conditions Min VOS Input Offset Voltage TCVOS Average Input Offset Voltage Drift, (Note 1) V mV/§ C a IIN a Input Current VS e g 5V, g 15V 0.5 3 I mA b IIN b Input Current VS e g 5V, g 15V 5 25 I mA CMRR Common Mode Rejection Ratio, (Note 2) VS e g 5V, g 15V I dB b ICMR b Input Current Common VS e g 5V, g 15V I mA/V I dB I mA/V 10 50 0.2 Mode Rejection, (Note 2) PSRR Power Supply Rejection Ratio, (Note 3) b IPSR b Input Current Power 75 Transimpedance, (Note 4) a RIN a Input Resistance a CIN a Input Capacitance CMIR Note Note Note Note Common Mode Input Range 5 95 0.2 Supply Rejection, (Note 3) ROL 55 5 VS e g 15V, RL e 400X 500 2000 I kX VS e g 15V, RL e 150X 500 1800 I kX MX 3 I PDIP package 1.5 1.5 V pF SOIC package 1 V pF VS e g 15V g 13.5 V V VS e g 5V g 3.5 V V 1: Measured from TMIN to TMAX. 2: VCM e g 10V for VS e g 15V, VCM e g 3V for VS e g 5V. 3: The supplies are moved from g 2.5V to g 15V. 4: VOUT e g 7V for VS e g 15V, VOUT e g 2V for VS e g 5V. 2 TD is 3.4in DC Electrical Characteristics VS e g 15V, RL e 150X, TA e 25§ C unless otherwise specified EL2360C Triple 130 MHz Current Feedback Amplifier Parameter VO Description Output Voltage Swing Test Level Units g 13.5 I V g 12 V V Conditions Min Typ VS e g 15V, RL e 400X g 12 VS e g 15V, RL e 150X VS e g 5V, RL e 150X Max g 3.0 g 3.7 I V 60 100 150 I mA VS e g 15V 8.0 11.3 I mA VS e g 5V 5.7 8.8 I mA ISC Output Short Circuit Current, (Note 5) VS e g 5V, g 15V IS Supply Current (per amplifier) TD is 1.5in DC Electrical Characteristics VS e g 15V, RL e 150X, TA e 25§ C unless otherwise specified Ð Contd. Note 5: A heat sink is required to keep junction temperature below absolute maximum when an output is shorted. AC Electrical Characteristics (Note 8), VS e g 15V, AV e a 2, RF e RG e 560X, RL e 150X, TA e 25§ C Parameter BW SR Description b 3 dB Bandwidth Slew Rate (Note 6) Conditions VS e g 15V, AV e a 2 Rise Time, Fall Time Typ 130 Max Test Level Units V MHz VS e g 15V, AV e a 1 180 V MHz VS e g 5V, AV e a 2 100 V MHz VS e g 5V, AV e a 1 110 V MHz 1500 IV V/ms 1500 V V/ms VOUT e g 500 mV 2.7 V ns RL e 400X 1000 RF e 1 kX, RG e 110X, RL e 400X tr, tf Min tPD Propagation Delay VOUT e g 500 mV 3.2 V ns OS Overshoot VOUT e g 500 mV 0 V % tS 0.1% Settling Time VOUT e g 2.5V, AV e b1 35 V ns dG Differential Gain (Note 7) RL e 150X 0.025 V % RL e 500X 0.006 V % RL e 150X 0.1 V § RL e 500X 0.005 V § dP Differential Phase (Note 7) Note 6: Slew Rate is with VOUT from a 10V to b10V and measured at a 5V and b5V. Note 7: DC offset from b0.714V to a 0.714V, AC amplitude 286 mVPbP, f e 3.58 MHz. Note 8: All AC tests are performed on a ‘‘warmed up’’ part, except Slew Rate, which is pulse tested. 3 TD is 3.0in unless otherwise specified. EL2360C Triple 130 MHz Current Feedback Amplifier Typical Performance Curves Non-Inverting Frequency Response (Gain) Inverting Frequency Response (Gain) 3 dB Bandwidth vs Supply Voltage for AV e b 1 Non-Inverting Frequency Response (Phase) Inverting Frequency Response (Phase) Peaking vs Supply Voltage for AV e b 1 Frequency Response for Various RL Frequency Response for Various RF and RG 3 dB Bandwidth vs Temperature for AV e b 1 2360 – 2 4 EL2360C Triple 130 MHz Current Feedback Amplifier Typical Performance Curves Ð Contd. 3 dB Bandwidth vs Supply Voltage for AV e a 1 Peaking vs Supply Voltage for AV e a 1 3 dB Bandwidth vs Temperature for AV e a 1 3 dB Bandwidth vs Supply Voltage for AV e a 2 Peaking vs Supply Voltage for AV e a 2 3 dB Bandwidth vs Temperature for AV e a 2 3 dB Bandwidth vs Supply Voltage for AV e a 10 Peaking vs Supply Voltage for AV e a 10 3 dB Bandwidth vs Temperature for AV e a 10 2360 – 3 5 EL2360C Triple 130 MHz Current Feedback Amplifier Typical Performance Curves Ð Contd. Frequency Response for Various CL Frequency Response for Various CIN b Channel to Channel Isolation vs Frequency PSRR and CMRR vs Frequency 2nd and 3rd Harmonic Distortion vs Frequency Transimpedance (ROL) vs Frequency Voltage and Current Noise vs Frequency Closed-Loop Output Impedance vs Frequency Transimpedance (ROL) vs Die Temperature 2360 – 4 6 EL2360C Triple 130 MHz Current Feedback Amplifier Typical Performance Curves Ð Contd. Offset Voltage vs Die Temperature (4 Samples) Supply Current vs Die Temperature (Per Amplifier) Supply Current vs Supply Voltage (Per Amplifier) a Input Resistance vs Die Temperature Input Current vs Die Temperature a Input Bias Current vs Input Voltage Output Voltage Swing vs Die Temperature Short Circuit Current vs Die Temperature PSRR & CMRR vs Die Temperature 2360 – 5 7 EL2360C Triple 130 MHz Current Feedback Amplifier Typical Performance Curves Ð Contd. Differential Gain vs DC Input Voltage, RL e 150 Differential Phase vs DC Input Voltage, RL e 150 Small Signal Pulse Response Differential Gain vs DC Input Voltage, RL e 500 Differential Phase vs DC Input Voltage, RL e 500 Large Signal Pulse Response Slew Rate vs Supply Voltage Slew Rate vs Temperature 2360 – 6 8 EL2360C Triple 130 MHz Current Feedback Amplifier Typical Performance Curves Ð Contd. Settling Time vs Settling Accuracy Long Term Settling Error 2360 – 16 2360 – 15 16-Lead Plastic SO Maximum Power Dissipation vs Ambient Temperature 16-Lead Plastic DIP Maximum Power Dissipation vs Ambient Temperature 2360 – 7 2360 – 8 9 EL2360C Triple 130 MHz Current Feedback Amplifier Differential Gain And Phase Test Circuit 2360 – 9 Simplified Schematic (One Amplifier) 2360 – 10 10 EL2360C Triple 130 MHz Current Feedback Amplifier Applications Information Product Description Capacitance at the Inverting Input The EL2360C is a triple current feedback amplifier that offers wide bandwidth and good video specifications at moderately low supply currents. It is built using Elantec’s proprietary complimentary bipolar process and is offered in both a 16 pin PDIP and SOIC packages. Due to the current feedback architecture, the EL2360C closed b loop b 3 dB bandwidth is dependent on the value of the feedback resistor. First the desired bandwidth is selected by choosing the feedback resistor, RF, and then the gain is set by picking a gain resistor, RG. The curves at the beginning of the Typical Performance Curves section show the effect of varying both RF and RG. The b 3 dB bandwidth is somewhat dependent on the power supply voltage. As the supply voltage is decreased, internal junction capacitances increase, causing a reduction in the closed loop bandwidth. To compensate for this, smaller values of feedback resistor can be used at lower supply voltages. Any manufacturer’s high-speed voltage- or current-feedback amplifier can be affected by stray capacitance at the inverting input. The characteristic curve of gain vs. frequency with variations in CIN b emphasizes this effect. The curve illustrates how the bandwidth can be extended to beyond 200 MHz with some additional peaking with an additional 2pF of capacitance at the VIN b pin. For inverting gains, this parasitic capacitance has little effect because the inverting input is a virtual ground, but for non-inverting gains, this capacitance (in conjunction with the feedback and gain resistors) creates a pole in the feedback path of the amplifier. This pole, if low enough in frequency, has the same destabilizing effect as a zero in the forward open-loop response. The use of large value feedback and gain resistors further exacerbates the problem by further lowering the pole frequency. Feedback Resistor Values The EL2360C has been designed and specified at a gain of a 2 with RF e 560X. This value of feedback resistor yields relatively flat frequency response with little to no peaking out to 130 MHz. Since the EL2360C is a current-feedback amplifier, it is also possible to change the value of RF to get more bandwidth. As seen in the curve of Frequency Response For Various RF and RG, bandwidth and peaking can be easily modified by varying the value of the feedback resistor. For example, by reducing RF to 430X, bandwidth can be extended to 170 MHz with under 1 dB of peaking. Further reduction of RF to 360X increases the bandwidth to 195 MHz with about 2.5 dB of peaking. Power Supply Bypassing and Printed Circuit Board Layout As with any high-frequency device, good printed circuit board layout is necessary for optimum performance. Ground plane construction is highly recommended. Lead lengths should be as short as possible, preferably below (/4’’. The power supply pins must be well bypassed to reduce the risk of oscillation. The combination of a 1.0 mF tantalum capacitor in parallel with a 0.01 mF ceramic capacitor has been shown to work well when placed at each supply pin. For good AC performance, parasitic capacitance should be kept to a minimum especially at the inverting input (see the Capacitance at the Inverting Input section). This implies keeping the ground plane away from this pin. Carbon or Metal-Film resistors are acceptable with the MetalFilm resistors giving slightly less peaking and bandwidth because of their additional series inductance. Use of sockets, particularly for the SO package should be avoided if possible. Sockets add parasitic inductance and capacitance which will result in some additional peaking and overshoot. Bandwidth vs Temperature Whereas many amplifier’s supply current and consequently b 3 dB bandwidth drop off at high temperature, the EL2360C was designed to have little supply current variation with temperature. An immediate benefit from this is that the b 3 dB bandwidth does not drop off drastically with temperature. With VS e g 15V and AV e a 2, the bandwidth varies only from 150 MHz to 110 MHz over the entire die junction temperature range of b 50§ C k T k 150§ C. 11 EL2360C Triple 130 MHz Current Feedback Amplifier Applications Information Ð Contd. caused by a power dissipation differential (before and after the voltage step). For AV e b 1, due to the inverting mode configuration, this tail does not appear since the input stage does not experience the large voltage change as in the non-inverting mode. With AV e b 1, 0.01% settling time is slightly greater than 100 ns. Supply Voltage Range and Single Supply Operation The EL2360C has been designed to operate with supply voltages from g 2V to g 15V. Optimum bandwidth, slew rate, and video characteristics are obtained at higher supply voltages. However, at g 2V supplies, the b 3 dB bandwidth at AV e a 2 is a respectable 70 MHz. The following figure is an oscilloscope plot of the EL2360C at g 2V supplies, AV e a 2, RF e RG e 560X, driving a load of 150X, showing a clean g 600 mV signal at the output. Power Dissipation The EL2360C amplifier combines both high speed and large output current capability at a moderate supply current in very small packages. It is possible to exceed the maximum junction temperature allowed under certain supply voltage, temperature, and loading conditions. To ensure that the EL2360C remains within it’s absolute maximum ratings, the following discussion will help to avoid exceeding the maximum junction temperature. The maximum power dissipation allowed in a package is determined according to  : PDMAX e 2360 – 11 TJMAX b TAMAX  iJA where: If a single supply is desired, values from a 4V to a 30V can be used as long as the input common mode range is not exceeded. When using a single supply, be sure to either 1) DC bias the inputs at an appropriate common mode voltage and AC couple the signal, or 2) ensure the driving signal is within the common mode range of the EL2360C, which is typically 1.5V from each supply rail. TJMAX e Maximum Junction Temperature TAMAX e Maximum Ambient Temperature iJA e Thermal Resistance of the Package PDMAX e Maximum Power Dissipation in the Package. The maximum power dissipation actually produced by an IC is the total quiescent supply current times the total power supply voltage, plus the power in the IC due to the load, or  Settling Characteristics PDMAX e N*(VS * ISMAX a (VS bVOUT) * The EL2360C offers superb settling characteristics to 0.1%, typically in the 35 ns to 40 ns range. There are no aberrations created from the input stage which often cause longer settling times in other current feedback amplifiers. The EL2360C is not slew rate limited, therefore any size step up to g 10V gives approximately the same settling time. VOUT RL )  where: Ne Number of amplifiers VS e Total Supply Voltage ISMAX e Maximum Supply Current per amplifier VOUT e Maximum Output Voltage of the Application RL e Load Resistance tied to Ground As can be seen from the Long Term Settling Error curve, for AV e a 1, there is approximately a 0.035% residual which tails away to 0.01% in about 40 ms. This is a thermal settling error 12 EL2360C Triple 130 MHz Current Feedback Amplifier Applications Information Ð Contd. If we set the two PDMAX equations,  and  , equal to each other, and solve for VS, we can get a family of curves for various loads and output voltages according to  : RL*(TJMAX b TAMAX) VS e N*iJA Current Limit The EL2360C has internal current limits that protect the circuit in the event of an output being shorted to ground. This limit is set at 100 mA nominally and reduces with the junction temperature. At TJ e 150§ C, the current limits at about 65 mA. If any one output is shorted to ground, the power dissipation could be well over 1W, and much greater if all outputs are shorted. Heat removal is required in order for the EL2360C to survive an indefinite short. a (VOUT)2 (IS*RL) a VOUT  The figures below show total supply voltage VS vs RL for various output voltage swings for the PDIP and SOIC packages. The curves assume WORST CASE conditions of TA e a 85§ C and IS e 11.3 mA per amplifier. The curves do not include heat removal or forcing air, or the simple fact that the package will be attached to a circuit board, which can also provide some form of heat removal. Larger temperature and voltage ranges are possible with heat removal and forcing air past the part. Driving Cables and Capacitive Loads When used as a cable driver, double termination is always recommended for reflection-free performance. For those applications, the back-termination series resistor will de-couple the EL2360C from the cable and allow extensive capacitive drive. However, other applications may have high capacitive loads without a back-termination resistor. In these applications, a small series resistor (usually between 5X and 50X) can be placed in series with the output to eliminate most peaking. The gain resistor (RG) can then be chosen to make up for any gain loss which may be created by this additional resistor at the output. In many cases it is also possible to simply increase the value of the feedback resistor (RF) to reduce the peaking. Supply Voltage vs RL for Various VOUT (PDIP Package) 2360 – 12 Supply Voltage vs RL for Various VOUT (SOIC Package) 2360 – 13 13 EL2360C Triple 130 MHz Current Feedback Amplifier * Transimpedance Stage * g1 0 18 17 0 1.0 rol 18 0 2Meg cdp 18 0 2.285pF * * Output Stage * q1 4 18 19 qp q2 7 18 20 qn q3 7 19 21 qn q4 4 20 22 qp r7 21 6 4 r8 22 6 4 ios1 7 19 2mA ios2 20 4 2mA * * Supply Current * ips 7 4 2.5mA * * Error Terms * ivos 0 23 2mA vxx 23 0 0V e4 24 0 3 0 1.0 e5 25 0 7 0 1.0 e6 26 0 4 0 b1.0 r9 24 23 562 r10 25 23 1K r11 26 23 1K * * Models * .model qn npn(is e 5eb15 bf e 100 tf e 0.1 ns) .model qp pnp(is e 5eb15 bf e 100 tf e 0.1 ns) .model dclamp d(is e 1eb30 ibv e 0.266 a bv e 2.24v n e 4) .ends * EL2360C Macromodel * Revision A, June 1996 * AC characteristics used: Rf e Rg e 560 ohms * Pin numbers reflect a standard single opamp a input * Connections: b input * l a Vsupply * l l b Vsupply * l l l * output l l l l * l l l l l .subckt EL2360/EL 3 2 7 4 6 * * Input Stage * e1 10 0 3 0 1.0 vis 10 9 0V h2 9 12 vxx 1.0 r1 2 11 130 l1 11 12 25nH iinp 3 0 0.5mA iinm 2 0 5mA r12 3 0 2 Meg * * Slew Rate Limiting * h1 13 0 vis 600 r2 13 14 1K d1 14 0 dclamp d2 0 14 dclamp * * High Frequency Pole * e2 30 0 14 0 0.00166666666 l3 30 17 0.43mH c5 17 0 0.27pF r5 17 0 500 * 14 TD is 5.1in TD is 4.8in EL2360C Macromodel EL2360C Triple 130 MHz Current Feedback Amplifier EL2360C Macromodel Ð Contd. 2360 – 14 15 EL2360C EL2360C Triple 130 MHz Current Feedback Amplifier General Disclaimer Specifications contained in this data sheet are in effect as of the publication date shown. Elantec, Inc. reserves the right to make changes in the circuitry or specifications contained herein at any time without notice. Elantec, Inc. assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement. June 1996 Rev A WARNING Ð Life Support Policy Elantec, Inc. products are not authorized for and should not be used within Life Support Systems without the specific written consent of Elantec, Inc. Life Support systems are equipment intended to support or sustain life and whose failure to perform when properly used in accordance with instructions provided can be reasonably expected to result in significant personal injury or death. Users contemplating application of Elantec, Inc. products in Life Support Systems are requested to contact Elantec, Inc. factory headquarters to establish suitable terms & conditions for these applications. Elantec, Inc.’s warranty is limited to replacement of defective components and does not cover injury to persons or property or other consequential damages. Elantec, Inc. 1996 Tarob Court Milpitas, CA 95035 Telephone: (408) 945-1323 (800) 333-6314 Fax: (408) 945-9305 European Office: 44-71-482-4596 16 Printed in U.S.A.