EL2260, EL2460 ® Data Sheet Dual/Quad 130MHz Current Feedback Amplifiers The EL2260/EL2460 are dual/quad current feedback operational amplifiers with -3dB bandwidth of 130MHz at a gain of +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 operational amplifier. The EL2260/EL2460 are designed to drive a double terminated 75Ω coax cable to video levels. Differential gain and phase are excellent when driving both loads of 500Ω (< 0.01%/< 0.01°) and double terminated 75Ω cables (0.025%/0.1°). The amplifiers can operate on any supply voltage from 4V (±2V) to 33V (±16.5V), yet consume only 7.5mA per amplifier at any supply voltage. Using industry standard pinouts, the EL2260 is available in 8-pin PDIP and 8-pin SO packages, while the EL2460 is available in 14-pin PDIP and 14-pin SO packages. January 1995, Rev B FN7064 Features • 130MHz 3dB bandwidth (AV = +2) • 180MHz 3dB bandwidth (AV = +1) • 0.01% differential gain, RL = 500Ω • 0.01° differential phase, RL = 500Ω • Low supply current, 7.5mA per amplifier • Wide supply range, ±2V to ±15V • 80mA output current (peak) • Low cost • 1500V/µs slew rate • Input common mode range to within 1.5V of supplies • 35ns settling time to 0.1% Applications • Video amplifiers Elantec’s facilities comply with MIL-I-45208A and offer applicable quality specifications. For information on Elantec’s processing, see the Elantec document, QRA-1: Elantec’s Processing—Monolithic Products. • Cable drivers Pinouts • Current to voltage converter • RGB amplifiers • Test equipment amplifiers Ordering Information EL2460 (14-PIN SO, PDIP) TOP VIEW EL2260 (8-PIN SO, PDIP) TOP VIEW 1 PART NUMBER TEMP. RANGE PACKAGE PKG. NO. EL2260CN -40°C to +85°C 8-Pin PDIP MDP0031 EL2260CS -40°C to +85°C 8-Pin SOIC MDP0027 EL2460CN -40°C to +85°C 14-Pin PDIP MDP0031 EL2460CS -40°C to +85°C 14-Pin SOIC MDP0027 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 321-724-7143 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright © Intersil Americas Inc. 2003. All Rights Reserved. Elantec is a registered trademark of Elantec Semiconductor, Inc. All other trademarks mentioned are the property of their respective owners. EL2260, EL2460 Absolute Maximum Ratings (TA = 25°C) Voltage between VS+ and VS- . . . . . . . . . . . . . . . . . . . . . . . . . .+33V Voltage between +IN and -IN . . . . . . . . . . . . . . . . . . . . . . . . . . . .±6V Current into +IN or -IN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10mA Internal Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . See Curves Operating Ambient Temperature Range . . . . . . . . . .-40°C to +85°C Operating Junction Temperature Plastic Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C Storage Temperature Range . . . . . . . . . . . . . . . . . .-65°C to +150°C Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±50mA CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typical values are for information purposes only. Unless otherwise noted, all tests are at the specified temperature and are pulsed tests, therefore: TJ = TC = TA Open-Loop DC Electrical Specifications VS = ±15V, RL = 150Ω, TA = 25°C unless otherwise specified. LIMITS PARAMETER VOS DESCRIPTION Input Offset Voltage CONDITIONS VS = ±5V, ±15V TEMP MIN 25°C TYP MAX 2 10 mV 15 mV TMIN, TMAX TC VOS Average Offset Voltage Drift (Note 1) +IIN +Input Current VS = ±5V, ±15V Full 10 25°C 0.5 TMIN, TMAX -IIN -Input Current VS = ±5V, ±15V 25°C 5 TMIN, TMAX CMRR Common Mode Rejection Ratio (Note 2) VS = ±5V, ±15V Full -ICMR -Input Current Common Mode Rejection (Note 2) VS = ±5V, ±15V 25°C Power Supply Rejection Ratio (Note 3) Full -IPSR -Input Current Power Supply Rejection (Note 3) 25°C Transimpedance (Note 4) VS = ±15V RL = 400Ω +Input Resistance +CIN +Input Capacitance CMIR Common Mode Input Range VO ISC Output Voltage Swing Output Short Circuit Current (Note 5) 2 0.2 25°C 500 TMIN, TMAX 250 25°C 500 TMIN, TMAX 250 Full 1.5 5 µA 10 µA 25 µA 35 µA dB 5 µA/V 5 µA/V 95 TMIN, TMAX VS = ±5V RL = 150Ω +RIN 0.2 75 µV/°C 55 TMIN, TMAX PSRR ROL 50 UNITS dB 5 µA/V 5 µA/V 2000 kΩ kΩ 1800 kΩ kΩ 3.0 MΩ 25°C 2.5 pF VS = ±15V 25°C ±13.5 V VS = ±5V 25°C ±3.5 V RL = 400Ω, VS =±15V 25°C ±12 ±13.5 V TMIN, TMAX ±11 RL = 150Ω, VS =±15V 25°C RL = 150Ω, VS =±5V 25°C ±3.0 TMIN, TMAX ±2.5 25°C 60 VS = ±5V, VS = ±15V V ±12 V ±3.7 V V 100 150 mA EL2260, EL2460 Open-Loop DC Electrical Specifications VS = ±15V, RL = 150Ω, TA = 25°C unless otherwise specified. (Continued) LIMITS PARAMETER IS DESCRIPTION Supply Current (Per Amplifier) CONDITIONS TEMP VS = ±15V MIN 25°C TYP MAX 7.5 11.0 mA 11.0 mA 8.5 mA 8.5 mA TMIN, TMAX VS = ±5V 25°C 5.4 TMIN, TMAX ROL Transimpedance (Note 6) VS = ±15V RL = 400Ω 25°C 500 UNITS 2000 kΩ NOTES: 1. Measured from TMIN to TMAX. 2. VCM = ±10V for VS = ±15V and TA= Full VCM = ±3V for VS = ±5V and TA = 25°C VCM = ±2V for VS = ±5V and TA = TMIN, TMAX 3. The supplies are moved from ±2.5V to ±15V. 4. The supplies are moved from ±2.5V to ±15V. 5. A heat sink is required to keep junction temperature below absolute maximum when an output is shorted. 6. The supplies are moved from ±2.5V to ±15V. Closed-Loop AC Electrical Specifications VS = ±15V, AV = +2, RF = 560Ω, RL = 150Ω, TA = 25°C unless otherwise noted LIMITS PARAMETER BW SR DESCRIPTION -3dB Bandwidth (Note 1) Slew Rate (Note 1) (Note 2) TEST CONDITIONS MIN TYP UNITS MAX VS = ±15V, AV = +2 130 MHz VS = ±15V, AV = +1 180 MHz VS = ±5V, AV = +2 100 MHz VS = ±5V, AV = +1 110 MHz 1500 V/µs 1500 V/µs 2.7 ns 3.2 ns RL = 400Ω 1000 RF = 1kΩ, RG = 110Ω RL = 400Ω tR, tF Rise Time, Fall Time (Note 1) tPD Propagation Delay (Note 1) OS Overshoot (Note 1) VOUT = ±500mV 0 % tS 0.1% Settling Time (Note 1) VOUT = ±10V 35 ns RL = 150Ω 0.025 % RL = 500Ω 0.006 % RL = 150Ω 0.1 deg (°) RL = 500Ω 0.005 deg (°) VOUT = ±500mV AV = -1, RL = 1k dG dP Differential Gain (Note 1)(Note 3) Differential Phase (Note 1)(Note 3) NOTES: 1. All AC tests are performed on a “warmed up” part, except for Slew Rate, which is pulse tested. 2. Slew Rate is with VOUT from +10V to -10V and measured at the 25% and 75% points. 3. DC offset from -0.714V through +0.714V, AC amplitude 286mVP-P, f = 3.58MHz. 3 EL2260, EL2460 Typical Performance Curves Non-Inverting Frequency Response (Gain) Inverting Frequency Response (Gain) 3dB Bandwidth vs Supply Voltage for AV = -1 4 Non-Inverting Frequency Response (Phase) Inverting Frequency Response (Phase) Peaking vs Supply Voltage for AV = -1 Frequency Response for Various RL Frequency Response for Various RF and RG 3dB Bandwidth vs Temperature for AV = - 1 EL2260, EL2460 Typical Performance Curves (Continued) 3dB Bandwidth vs Supply Voltage for AV = +1 Peaking vs Supply Voltage for AV = +1 3dB Bandwidth vs Supply Voltage for AV = +2 Peaking vs Supply Voltage for AV = +2 3dB Bandwidth vs Supply Voltage for AV = +10 Peaking vs Supply Voltage for AV = +10 5 3dB Bandwidth vs Temperature for AV = +1 3dB Bandwidth vs Temperature for AV = +2 3dB Bandwidth vs Temperature for AV = +10 EL2260, EL2460 Typical Performance Curves Frequency Response for Various CL PSRR and CMRR vs Frequency Voltage and Current Noise vs Frequency 6 (Continued) Frequency Response for Various CIN- 2nd and 3rd Harmonic Distortion vs Frequency Closed-Loop Output Impedance vs Frequency Channel to Channel Isolation vs Frequency Transimpedance (ROL) vs Frequency Transimpedance (ROL) vs Die Temperature EL2260, EL2460 Typical Performance Curves Offset Voltage vs Die Temperature (4 Samples) +Input Resistance vs Die Temperature Output Voltage Swing vs Die Temperature 7 (Continued) Supply Current vs Die Temperature (Per Amplifier) Supply Current vs Supply Voltage (Per Amplifier) Input Current vs Die Temperature +Input Bias Current vs Input Voltage Short Circuit Current vs Die Temperature PSRR & CMRR vs Die Temperature EL2260, EL2460 Typical Performance Curves (Continued) Differential Gain vs DC Input Voltage, RL = 150 Differential Phase vs DC Input Voltage, RL = 150 Differential Gain vs DC Input Voltage, RL = 500 Differential Phase vs DC Input Voltage, RL = 500 Slew Rate vs Supply Voltage 8 Small Signal Pulse Response Large Signal Pulse Response Slew Rate vs Temperature EL2260, EL2460 Typical Performance Curves (Continued) Settling Time vs Settling Accuracy 14-Pin Plastic DIP Maximum Power Dissipation vs Ambient Temperature 14-Pin Plastic SO Maximum Power Dissipation vs Ambient Temperature Long Term Settling Error 8-Pin Plastic DIP Maximum Power Dissipation vs Ambient Temperature 8-Pin Plastic SO Maximum Power Dissipation vs Ambient Temperature Burn-In Circuits EL2460 EL2260 9 EL2260, EL2460 Differential Gain and Phase Test Circuit Simplified Schematic (One Amplifier) 10 EL2260, EL2460 Applications Information Product Description The EL2260/EL2460 are dual and quad current mode feedback amplifiers that offer wide bandwidths and good video specifications at moderately low supply currents. They are built using Elantec’s proprietary complimentary bipolar process and are offered in industry standard pinouts. Due to the current feedback architecture, the EL2260/EL2460 closed-loop 3dB 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 the gain resistor, RG. The curves at the beginning of the Typical Performance Curves section show the effect of varying both RF and RG. The 3dB bandwidth is somewhat dependent on the power supply voltage. As the supply voltage is decreased, internal junction capacitances increase, causing a reduction in closed loop bandwidth. To compensate for this, smaller values of feedback resistor can be used at lower supply voltages. 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, below 1/4”. The power supply pins must be well bypassed to reduce the risk of oscillation. A 1.0µF tantalum capacitor in parallel with a 0.01µF ceramic capacitor is adequate for each supply pin. For good AC performance, parasitic capacitances should be kept to a minimum, especially at the inverting input (see Capacitance at the Inverting Input section). This implies keeping the ground plane away from this pin. Carbon resistors are acceptable, while use of wire-wound resistors should not be used because of their parasitic inductance. Similarly, capacitors should be low inductance for best performance. Use of sockets, particularly for the SO packages, should be avoided. Sockets add parasitic inductance and capacitance which will result in peaking and overshoot. In the inverting gain mode, added capacitance at the inverting input has little effect since this point is at a virtual ground and stray capacitance is therefore not “seen” by the amplifier. Feedback Resistor Values The EL2260 and EL2460 have been designed and specified with RF = 560Ω for AV = +2. This value of feedback resistor yields extremely flat frequency response with little to no peaking out to 130MHz. As is the case with all current feedback amplifiers, wider bandwidth, at the expense of slight peaking, can be obtained by reducing the value of the feedback resistor. Inversely, larger values of feedback resistor will cause rolloff to occur at a lower frequency. By reducing RF to 430Ω, bandwidth can be extended to 170MHz with under 1dB of peaking. Further reduction of RF to 360Ω increases the bandwidth to 195MHz with about 2.5dB of peaking. See the curves in the Typical Performance Curves section which show 3dB bandwidth and peaking vs. frequency for various feedback resistors and various supply voltages. Bandwidth vs Temperature Whereas many amplifier’s supply current and consequently 3dB bandwidth drop off at high temperature, the EL2260/EL2460 were designed to have little supply current variations with temperature. An immediate benefit from this is that the 3dB bandwidth does not drop off drastically with temperature. With VS = ±15V and AV = +2, the bandwidth only varies from 150MHz to 110MHz over the entire die junction temperature range of 0°C < T < 150°C. Supply Voltage Range The EL2260/EL2460 has been designed to operate with supply voltages from ±2V to ±15V. Optimum bandwidth, slew rate, and video characteristics are obtained at higher supply voltages. However, at ±2V supplies, the 3dB bandwidth at AV = +2 is a respectable 70MHz. The following figure is an oscilloscope plot of the EL2260 at ±2V supplies, AV = +2, RF = RG = 560Ω, driving a load of 150Ω, showing a clean ±600mV signal at the output. Capacitance at the Inverting Input Due to the topology of the current feedback amplifier, stray capacitance at the inverting input will affect the AC and transient performance of the EL2260/EL2460 when operating in the non-inverting configuration. The characteristic curve of gain vs. frequency with variations of CIN- emphasizes this effect. The curve illustrates how the bandwidth can be extended to beyond 200MHz with some additional peaking with an additional 2pF of capacitance at the VIN- pin for the case of AV = +2. Higher values of capacitance will be required to obtain similar effects at higher gains. 11 If a single supply is desired, values from +4V to +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) EL2260, EL2460 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 EL2260/EL2460. Settling Characteristics The EL2260/EL2460 offer superb settling characteristics to 0.1%, typically in the 35ns to 40ns range. There are no aberrations created from the input stage which often cause longer settling times in other current feedback amplifiers. The EL2260/EL2460 are not slew rate limited, therefore any size step up to ±10V gives approximately the same settling time. As can be seen from the Long Term Settling Error curve, for AV = +1, there is approximately a 0.035% residual which tails away to 0.01% in about 40µs. This is a thermal settling error caused by a power dissipation differential (before and after the voltage step). For AV = -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 = -1, 0.01% settling time is slightly greater than 100ns. Power Dissipation The EL2260/EL2460 amplifiers combine both high speed and large output current drive 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 EL2260/EL2460 remain within their absolute maximum ratings, the following discussion will help to avoid exceeding the maximum junction temperature. Unlike some amplifiers, such as the LT1229 and LT1230, the EL2260/EL2460 maintain almost constant supply current over temperature so that AC performance is not degraded as much over the entire operating temperature range. Of course, this increase in performance doesn’t come for free. Since the current has increased, supply voltages must be limited so that maximum power ratings are not exceeded. Each amplifier in the EL2260/EL2460 consume typically 7.5mA and maximum 10.0mA. The worst case power in an IC occurs when the output voltage is at half supply, if it can go that far, or its maximum value if it cannot reach half supply. If we assume that the EL2260/EL2460 is used for double terminated video cable driving applications (RL = 150Ω), and the gain = +2, then the maximum output voltage is 2V, and the average output voltage is 1.4V. If we set the two PDmax equations equal to each other, and solve for VS, we can get a family of curves for various packages and conditions according to: R L × ( T JMAX – T AMAX ) --------------------------------------------------------------- + ( V OUT ) N × θ JA V S = -----------------------------------------------------------------------------------------( 2 × I S × R L ) + V OUT The following curve shows supply voltage (±VS) vs. temperature for the various packages assuming AV = + 2, RL = 150, and VOUT peak = 2V. The curves include worst case conditions (IS = 10mA and all amplifiers operating at VOUT peak = 2V). Supply Voltage vs Ambient Temperature for All Packages of EL2260/EL2460 The maximum power dissipation allowed in a package is determined by its thermal resistance and the amount of temperature rise according to: T JMAX – T AMAX P DMAX = -------------------------------------------θ JA 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 V OUT P DMAX = N × 2 × V S × I S + ( V S – V OUT ) × ---------------- RL where N is the number of amplifiers per package, and IS is the current per amplifier. (To be more accurate, the quiescent supply current flowing in the output driver transistor should be subtracted from the first term because, under loading and due to the class AB nature of the output stage, the output driver current is now included in the second term.) In general, an amplifier’s AC performance degrades at higher operating temperature and lower supply current. 12 The curves do not include heat removal or forcing air, or the simple fact that the package will probably 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. Current Limit The EL2260/EL2460 have internal current limits that protect the circuit in the event of the output being shorted to ground. This limit is set at 100mA nominally and reduces with junction temperature. At a junction temperature of 150°C, the current limits at about 65mA. 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 EL2260, EL2460 required in order for the EL2260/EL2460 to survive an indefinite short. Channel to Channel Isolation Due to careful biasing connections within the internal circuitry of the EL2260/EL2460, exceptionally good channel to channel isolation is obtained. Isolation is over 70dB at video frequencies of 4MHz, and over 65dB up to 10MHz. The EL2460 isolation is improved an additional 10dB, up to about 5MHz, for amplifiers A to B and amplifiers C to D. Isolation is improved another 8dB for amplifiers A to C and amplifiers B to D. See the curve in the Typical Performance Curves section for more detail. 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 decouple the EL2260 and EL2460 from the capacitive cable and allow extensive capacitive drive. However, other applications may have high capacitive loads without termination resistors. In these applications, an additional small value (5Ω–50Ω) resistor in series with the output will eliminate most peaking. The gain resistor, RG, can be chosen to make up for the gain loss created by this additional series resistor at the output. 13 EL2260, EL2460 EL2260/EL2460 Macromodel * Revision A, March 1993 * AC Characteristics used CIN- (pin 2) = 1pF; RF = 560Ω * Connections: +input * | -input * | | +Vsupply * | | | -Vsupply * | | | | output * | | | | | .subckt EL2260/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 0.5µA iinm 2 0 5µA r12 3 0 2Meg * * 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 0.43µH c5 17 0 0.27pF r5 17 0 500 * * Transimpedance Stage * g1 0 18 17 0 1.0 ro1 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 2mA * * Error Terms * ivos 0 23 2mA 14 EL2260, EL2460 vxx 23 0 0V e4 24 0 3 0 1.0 e5 25 0 7 0 1.0 e6 26 0 4 0 1.0 r9 24 23 562 r10 25 23 1K r11 26 23 1K * * Models * .model qn npn (is=5e-15 bf=100 tf=0.1ns) .model qp pnp (is=5e-15 bf=100 tf=0.1ns) .model dclamp d (is=1e-30 ibv=0.266 bv=2.24 n=4) .ends All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems. Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 15